BEGIN:VCALENDAR
VERSION:2.0
PRODID:researchseminars.org
CALSCALE:GREGORIAN
X-WR-CALNAME:researchseminars.org
BEGIN:VEVENT
SUMMARY:Maxim Chernodub (Institut Denis Poisson\, Université de Tours\, F
rance)
DTSTART:20211116T130000Z
DTEND:20211116T140000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/1
DESCRIPTION:Title: Machine-learning applied to deconfinement phase transitions and
topological defects\nby Maxim Chernodub (Institut Denis Poisson\, Uni
versité de Tours\, France) as part of Seed Seminar of Mathematics and Phy
sics\n\n\nAbstract\nWe discuss the advantages of machine learning techniqu
es in recognizing the dynamics of topological objects and building order p
arameters associated with phase transitions in lattice quantum field theor
ies. We consider the compact $U(1)$ gauge theory in three spacetime dimens
ions as the simplest example of a theory that exhibits confinement and mas
s gap phenomena generated by monopoles. We train a neural network with a M
onte-Carlo generated set of monopole configurations\, treated as three-dim
ensional holograms\, to distinguish between confinement and deconfinement
phases in a supervised learning approach. We show that a well-trained neur
al network may distinguish between confining and nonconfining monopole con
figurations "from a single glimpse'' with reasonable accuracy. As a second
example\, we discuss the ability of a neural network to (re)build a gauge
-invariant deconfinement order parameter in the finite-temperature lattice
Yang-Mills theory. Some comments on current-state applications of machine
learning techniques to lattice gauge theories will also be given.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/1/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Thomas Richard (LAMA\, CNRS and Université Paris-Est Créteil\, F
rance)
DTSTART:20211130T150000Z
DTEND:20211130T160000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/2
DESCRIPTION:Title: Quantitative implications of positive scalar curvature\nby
Thomas Richard (LAMA\, CNRS and Université Paris-Est Créteil\, France) a
s part of Seed Seminar of Mathematics and Physics\n\n\nAbstract\nCompariso
n inequalities (Toponogov\, Myers\, Bishop-Gromov) are essential tools in
studying manifolds with positive sectional or Ricci curvature. Until recen
tly\, these tools had no analog in the context of manifolds with positive
scalar curvature: all\nthe results on these kinds of manifolds were topolo
gical in nature.\nWe will present more or less recent progress in this dir
ection due to Gromov using minimal hypersurfaces as well as what Gromov ca
lls the “mu-bubbles.” In particular\, we will show that a metric with
scalar curvature greater than $ n(n-1)$ on $\\mathbb{T}^{n-1} \\times [-1\
,1]\\\; (n \\leq 7) $\ncannot have its two boundary components too far a
part. We will conclude by showing how the positive scalar curvature contro
ls the size of minimal 2-spheres in $ \\mathbb{S}_2 \\times \\mathbb{T}^{n
-2}\, \\mathbb{S}_2 \\times \\mathbb{R}^2 $ and $ \\mathbb{S}_2 \\times
\\mathbb{S}_2$.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/2/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Yoshimasa Hidaka (Institute of Particle and Nuclear Studies\, KEK\
, Japan)
DTSTART:20211214T110000Z
DTEND:20211214T120000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/3
DESCRIPTION:Title: Generalization of the Nambu-Goldstone theorem\nby Yoshimasa
Hidaka (Institute of Particle and Nuclear Studies\, KEK\, Japan) as part
of Seed Seminar of Mathematics and Physics\n\n\nAbstract\nSymmetry and its
spontaneous breaking are basic concepts in modern physics. When a continu
um symmetry is spontaneously broken\, there appears a gapless mode called
the Nambu-Goldstone (NG) mode\, which is developed in a Lorentz invariant
system\, and is known as the Nambu-Goldstone theorem. In this talk\, we di
scuss the generalization of the Nambu-Goldstone theorem to various systems
: a non-relativistic system\, a system with higher-form symmetries\, and o
pen classical and quantum systems. We will show that there also appears an
NG mode in these systems when symmetry is spontaneously broken.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/3/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Clotilde Fermanian-Kammerer (LAMA\, CNRS and Université Paris-Est
Créteil\, France)
DTSTART:20220118T130000Z
DTEND:20220118T140000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/4
DESCRIPTION:Title: Semi-classical analysis and the correspondence principle\nb
y Clotilde Fermanian-Kammerer (LAMA\, CNRS and Université Paris-Est Crét
eil\, France) as part of Seed Seminar of Mathematics and Physics\n\n\nAbst
ract\nIn this talk\, we will explain the basis of the semi-classical appro
ach\, some of the ideas and results obtained in this context and we will d
escribe its position at the interface between mathematics and physics or t
heoretical chemistry.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/4/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Kazuya Mameda (RIKEN\, Japan)
DTSTART:20220201T100000Z
DTEND:20220201T110000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/5
DESCRIPTION:Title: Quantum kinetic theory in curved spacetime\nby Kazuya Mamed
a (RIKEN\, Japan) as part of Seed Seminar of Mathematics and Physics\n\n\n
Abstract\nIn this talk\, I will explain my recent works about the kinetic
theory under external gravity. I will first show its field-theoretical der
ivation keeping the general covariance. From this framework\, we obtain ne
w types of fermionic transport phenomena induced by gravity\; in particula
r\, the coupling between spin and Riemann curvature yields the antiparalle
l flows of charge and energy. These phenomena are applicable not only to f
ermionic systems under genuine gravity\, but also to the ones with backgro
und fluid motion or temperature gradient. I will briefly discuss possible
applications to high-energy and condensed matter physics. I will also talk
about photonic kinetic theory in curved spacetime and its implication.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/5/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Giacomo De Palma (University of Bologna\, Italy)
DTSTART:20220215T130000Z
DTEND:20220215T140000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/6
DESCRIPTION:Title: The quantum Wasserstein distance of order 1\nby Giacomo De
Palma (University of Bologna\, Italy) as part of Seed Seminar of Mathemati
cs and Physics\n\n\nAbstract\nWe propose a generalization of the Wasserste
in distance of order 1 to the quantum states of n\n qudits. The proposal r
ecovers the Hamming distance for the vectors of the canonical basis\, and
more generally the classical Wasserstein distance for quantum states diago
nal in the canonical basis. The proposed distance is invariant with respec
t to permutations of the qudits and unitary operations acting on one qudit
and is additive with respect to the tensor product. We prove a continuity
bound for the von Neumann entropy with respect to the proposed distance\,
which significantly strengthens the best continuity bound with respect to
the trace distance. We also propose a generalization of the Lipschitz con
stant to quantum observables. The notion of quantum Lipschitz constant all
ows us to compute the proposed distance with a semidefinite program. We pr
ove a quantum version of Marton’s Transportation-Cost Inequality (TCI) f
or product states and a quantum Gaussian concentration inequality for the
spectrum of quantum Lipschitz observables. Furthermore\, we prove two gene
ralizations of Marton’s TCI to Gibbs states of quantum commuting Hamilto
nians. The first relies on a quantum generalization of Dobrushin’s uniqu
eness condition\, while the second relies on a quantum generalization of O
llivier’s coarse Ricci curvature. Finally\, we apply our results to prov
e the equivalence of the canonical and microcanonical ensembles of quantum
statistical mechanics.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/6/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Mahmut Elbistan (Bogazici University\, Turkey)
DTSTART:20220301T130000Z
DTEND:20220301T140000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/7
DESCRIPTION:Title: Circularly polarized periodic gravitational wave and the Pais-U
hlenbeck oscillator\nby Mahmut Elbistan (Bogazici University\, Turkey)
as part of Seed Seminar of Mathematics and Physics\n\n\nAbstract\nThe “
Bargmann framework” allows us to prove the equivalence of the Pais-Uhlen
beck oscillator with a spin-zero particle in a circularly polarized period
ic gravitational wave. Pushing forward the symmetries (which include Carro
ll symmetry) of the latter\, we derive conserved charges for the Pais-Uhle
nbeck oscillator.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/7/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Thomas Raujouan (Institut für Differentialgeometrie\, University
of Hanover\, Germany)
DTSTART:20220315T130000Z
DTEND:20220315T140000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/8
DESCRIPTION:Title: Soap bubbles: a gauge theory\nby Thomas Raujouan (Institut
für Differentialgeometrie\, University of Hanover\, Germany) as part of S
eed Seminar of Mathematics and Physics\n\n\nAbstract\nConstant Mean Curvat
ure (CMC) surfaces are mathematical models for soap films\, with or withou
t volume constraints. The equations governing them form an integrable syst
em which can be formulated in a gauge theoretic point of view. This formul
ation leads to a generalized holomorphic representation for CMC surfaces i
n Euclidean\, Spherical and Hyperbolic three-spaces\, which allows for the
construction of new surfaces\, together with the computation of their are
as and proofs of their embeddedness.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/8/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Pietro Benetti Genolini (King's College London\, United Kingdom)
DTSTART:20220329T120000Z
DTEND:20220329T130000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/9
DESCRIPTION:Title: Localization of the action in AdS/CFT\nby Pietro Benetti Ge
nolini (King's College London\, United Kingdom) as part of Seed Seminar of
Mathematics and Physics\n\n\nAbstract\nI will introduce a simple formula
for the action of supersymmetric solutions to minimal gauged supergravity
in the context of the AdS/CFT correspondence. Such solutions are equipped
with a Killing vector\, and I will show that the holographically renormali
zed action may be expressed entirely in terms of the weights of this vecto
r field at its fixed points\, together with certain topological data. In t
his sense\, the classical gravitational partition function localizes in th
e bulk\, and depends only on the topology of the fixed point set.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/9/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Edoardo Lauria (École Polytechnique\, France)
DTSTART:20220419T120000Z
DTEND:20220419T130000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/10
DESCRIPTION:Title: Conformal boundary conditions for free fields\nby Edoardo
Lauria (École Polytechnique\, France) as part of Seed Seminar of Mathemat
ics and Physics\n\n\nAbstract\nI will discuss the problem of classifying (
interacting) conformal boundary conditions for the simplest bulk conformal
field theories: free fields. I will mention concrete examples based on pe
rturbation theory\, and then describe results using the numerical conforma
l bootstrap approach\, specifically in the case of a scalar field in four
and three bulk dimensions.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/10/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Utku Zorba (Bogazici University\, Turkey)
DTSTART:20220510T120000Z
DTEND:20220510T130000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/11
DESCRIPTION:Title: Carrollian and Non-relativistic Jackiw-Teitelboim Supergravity
\nby Utku Zorba (Bogazici University\, Turkey) as part of Seed Seminar
of Mathematics and Physics\n\n\nAbstract\nWe present non- and ultra-relat
ivistic Jackiw-Teitelboim (JT) supergravity as metric BF theories based on
the extended Newton-Hooke and extended $\\text{AdS}$ Carroll super-algebr
as in two spacetime dimensions\, respectively. The extended Newton-Hooke s
tructure\, and\, in particular\, the invariant metric necessary for the BF
construction of non-relativistic JT supergravity\, is obtained by perform
ing an expansion of the $N=2$ $\\text{AdS}$ super algebra. Subsequently\,
we introduce the extended $\\text{AdS}_2$ Carroll super algebra\, and the
associated invariant metric\, as a suitable redefinition of the extended N
ewton-Hooke super algebra. The mapping involved can be seen as the supersy
mmetric extension of the duality existing at the purely bosonic level betw
een the extended Newton-Hooke algebra with (positive) negative cosmologica
l constant and the extended $\\text{(A)dS}$ Carroll algebra in two dimensi
ons. Finally\, we provide the Carrollian JT supergravity action in the BF
formalism. Moreover\, we show that both the non-relativistic and the ultra
-relativistic theories presented can also be obtained by direct expansion
of $N=2$ JT supergravity.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/11/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Cristina Manuel (Instituto de Ciencias del Espacio\, Consejo Super
ior de Investigaciones Científicas\, Barcelona\, Spain)
DTSTART:20220517T120000Z
DTEND:20220517T130000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/12
DESCRIPTION:Title: Chiral Kinetic Theory with small mass corrections and quantum
coherent states\nby Cristina Manuel (Instituto de Ciencias del Espacio
\, Consejo Superior de Investigaciones Científicas\, Barcelona\, Spain) a
s part of Seed Seminar of Mathematics and Physics\n\n\nAbstract\nIn system
s made up of massless fermions\, the hydrodynamical equations have to incl
ude the effects of the chiral quantum anomaly. The so-called anomalous hyd
rodynamics might be derived from a microscopic approach\, chiral kinetic t
heory\, which contains quantum corrections to classical transport equation
s. We explain how quantum effects might be incorporated in transport theor
y\, using effective field theory techniques. We also study the effect of a
small fermion mass in the formulation of the chiral kinetic theory. Besid
es the left-handed and right-handed distribution functions components need
ed in the massless case\, distribution functions describing quantum cohere
nt mixtures of left and right-handed fermions are also required\, which al
so enter in the chiral anomaly equation. We study how these two different
sets of functions are related by Lorentz symmetry transformations.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/12/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Maurice de Gosson (Faculty of Mathematics (NuHAG)\, University of
Vienna\, Austria)
DTSTART:20220531T120000Z
DTEND:20220531T130000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/13
DESCRIPTION:Title: On the notions of mixed Gaussian quantum states and density op
erators\nby Maurice de Gosson (Faculty of Mathematics (NuHAG)\, Univer
sity of Vienna\, Austria) as part of Seed Seminar of Mathematics and Physi
cs\n\n\nAbstract\nOne cornerstone of quantum mechanics is the notion of mi
xed quantum state. In this talk\, we will give a mathematically rigorous d
efinition of this concept and of the associated notion of density operator
from the point of view of harmonic analysis and symplectic geometry. We w
ill discuss in detail the case of so-called gaussian states which play a m
ajor role in the applications to quantum information and optics.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/13/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Karl Landsteiner (Instituto de Física Teórica\, Consejo Superior
de Investigaciones Científicas\, Madrid\, Spain)
DTSTART:20220607T120000Z
DTEND:20220607T130000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/14
DESCRIPTION:Title: Quantum Anomalies and Matter\nby Karl Landsteiner (Institu
to de Física Teórica\, Consejo Superior de Investigaciones Científicas\
, Madrid\, Spain) as part of Seed Seminar of Mathematics and Physics\n\n\n
Abstract\nMassless fermions possess chiral symmetries on the classical lev
el. These symmetries are however broken by quantum effects. In particle ph
ysics they lead to the decay of the neutral pion and to important consiste
ncy constraints on chiral gauge theories such as the standard model. Anoma
lies also have important consequences at finite temperature and finite den
sity. they lead then to new transport effects\, the chiral magnetic and ch
iral vortical effects. I will review the theory of anomaly induced transpo
rt\, its application to condensed matter and high energy physics\, and giv
e an outlook on recent developments.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/14/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Quentin Berger (Laboratoire de Probabilités Statistique et Modél
isation\, Sorbonne Université\, Paris\, France)
DTSTART:20220621T120000Z
DTEND:20220621T130000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/15
DESCRIPTION:Title: Directed polymers and the Stochastic Heat Equation with heavy-
tail noise\nby Quentin Berger (Laboratoire de Probabilités Statistiqu
e et Modélisation\, Sorbonne Université\, Paris\, France) as part of See
d Seminar of Mathematics and Physics\n\n\nAbstract\nI will introduce the d
irected polymer model in dimension $1+d$\n\, which describes a one-dimensi
onal polymer chain placed in some disordered medium. I will give an overvi
ew of the model and I will discuss its relation to the stochastic heat equ
ation (SHE) with multiplicative noise. This has been widely studied in the
case where the disorder admits a second moment \; it corresponds to the S
HE with Gaussian white noise. I will then present the results obtained in
collaboration with Carsten Chong (Columbia\, USA) and Hubert Lacoin (IMPA\
, Brazil) on the directed polymer model and the SHE with Lévy noise.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/15/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Eveliina Peltola (Hausdorff Center for Mathematics\, University of
Bonn\, Germany\, and Aalto University\, Finland)
DTSTART:20221108T130000Z
DTEND:20221108T140000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/16
DESCRIPTION:Title: Towards a conformal field theory for Schramm-Loewner evolution
s?\nby Eveliina Peltola (Hausdorff Center for Mathematics\, University
of Bonn\, Germany\, and Aalto University\, Finland) as part of Seed Semin
ar of Mathematics and Physics\n\n\nAbstract\nFor a number of critical latt
ice models in $2D$\n statistical physics\, it has been proven that scaling
limits of interfaces (with suitable boundary conditions) are described by
Schramm-Loewner evolution (SLE) curves. So-called partition functions of
these SLEs (which also encode macroscopic crossing probabilities) can be r
egarded as specific correlation functions in the conformal field theory (C
FT) associated to the lattice model in question. Although it is not clear
how to define the latter mathematically\, one can still make sense of many
of the properties predicted for these CFTs. In particular\, all of the ex
pected CFT properties: conformal invariance\, null-field equations\, and f
usion rules\, are satisfied by the partition functions. One might then ask
: Is it possible to go deeper and to construct the appropriate CFT fields
as random distributions? Time permitting\, I discuss some ideas to this di
rection.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/16/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Kostas Skenderis (University of Southampton\, United Kingdom)
DTSTART:20221122T150000Z
DTEND:20221122T160000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/17
DESCRIPTION:Title: Conformal Field Theory in momentum space\nby Kostas Skende
ris (University of Southampton\, United Kingdom) as part of Seed Seminar o
f Mathematics and Physics\n\n\nAbstract\nI will give an overview of confor
mal field theory in momentum space. In particular\, I will present the sol
ution of conformal Ward identities for $n$-point correlation functions and
then discuss renormalisation and conformal anomalies.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/17/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Emilio Trevisani (École Polytechnique\, France)
DTSTART:20221213T130000Z
DTEND:20221213T140000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/18
DESCRIPTION:Title: Random field models and Parisi-Sourlas supersymmetry\nby E
milio Trevisani (École Polytechnique\, France) as part of Seed Seminar of
Mathematics and Physics\n\n\nAbstract\nThe problem of quenched disorder i
s very important but notoriously hard. In 1979\, Parisi and Sourlas propos
ed a conjecture about the critical behaviour of models with random field t
ype of disorder. The conjecture states that 1) such models have emergent s
upersymmetry and 2) that supersymmetry allows to describe them in terms of
models in two less dimensions. I will review the conjecture and explain s
ome recent developments on the subject.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/18/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Claudio Corianò (Department of Mathematics and Physics "Ennio De
Giorgi"\, University of Salento\, and INFN\, Lecce\, Italy)
DTSTART:20221220T130000Z
DTEND:20221220T140000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/19
DESCRIPTION:Title: Testing Anomaly Induced Actions using CFT in momentum space\nby Claudio Corianò (Department of Mathematics and Physics "Ennio De Gi
orgi"\, University of Salento\, and INFN\, Lecce\, Italy) as part of Seed
Seminar of Mathematics and Physics\n\n\nAbstract\nConformal field theory i
n momentum space provides the general framework for investigating effects
of conformal and chiral anomalies in parity even and parity odd conformal
correlators. The connection of the momentum space formalism with gravity i
s defined by the conformal anomaly effective action. This action summarize
s the conformal Ward identities of the flat space correlators in a general
framework\, and it accounts for the conformal anomaly. We are going to il
lustrate the relation between conformal anomaly actions\, the Conformal Wa
rd identities constraining the CFT correlators\, and the so-called “anom
aly induced actions”. An analysis of 4-point functions derived from such
actions appears to be inconsistent with the perturbative result. These in
vestigations find application in very different areas of physics\, from to
pological insulators to non-local gravity and Einstein-Gauss-Bonnet theori
es.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/19/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Bram Petri (Institut de Mathématiques de Jussieu-Paris Rive Gauch
e\, Sorbonne Université\, Paris\, France)
DTSTART:20230207T130000Z
DTEND:20230207T140000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/20
DESCRIPTION:Title: Linear programming on hyperbolic surfaces\nby Bram Petri (
Institut de Mathématiques de Jussieu-Paris Rive Gauche\, Sorbonne Univers
ité\, Paris\, France) as part of Seed Seminar of Mathematics and Physics\
n\n\nAbstract\nI will speak about extremal problems in the (spectral) geom
etry of hyperbolic surfaces and how linear programming methods based on th
e Selberg trace formula can help. I will not assume any familiarity with h
yperbolic geometry or the Selberg trace formula. This is joint work with M
axime Fortier Bourque.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/20/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Yannick Herfray (Institut Denis Poisson\, Université de Tours\, F
rance)
DTSTART:20230228T130000Z
DTEND:20230228T140000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/21
DESCRIPTION:Title: Geometrical asymptotics in General Relativity\nby Yannick
Herfray (Institut Denis Poisson\, Université de Tours\, France) as part o
f Seed Seminar of Mathematics and Physics\n\n\nAbstract\nIn general relati
vity there are several classical notions of asymptotic flatness: In effect
these amount to the possibility of “adding a boundary at infinity” to
the curved spacetime. The exact procedure and geometry is however very di
fferent depending on whether one considers an asymptote in null\, time-lik
e\, or space-like directions. I will show that these can nonetheless all b
e derived from one unique concept\, curved obit decomposition of Cartan ge
ometry\, and that there is therefore a profound unity in these notions of
asymptotics.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/21/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Alicia Castro (Radboud University\, Nijmegen\, the Netherlands)
DTSTART:20230328T110000Z
DTEND:20230328T120000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/22
DESCRIPTION:Title: Scale-invariant random geometries from mating of trees\nby
Alicia Castro (Radboud University\, Nijmegen\, the Netherlands) as part o
f Seed Seminar of Mathematics and Physics\n\n\nAbstract\nIn this talk\, I
present new results on the search for scale-invariant random geometries in
the context of Quantum Gravity. To uncover new universality classes of su
ch geometries\, we generalized the mating of trees approach\, which encode
s Liouville Quantum Gravity on the 2-sphere in terms of a correlated Brown
ian motion describing a pair of random trees. We extended this approacyouh
to higher-dimensional correlated Brownian motions\, leading to a family o
f non-planar random graphs that belong to new universality classes of scal
e-invariant random geometries. We developed a numerical method to efficien
tly simulate these random graphs and explore their scaling limits through
distance measurements\, allowing us to estimate Hausdorff dimensions in th
e two- and three-dimensional settings.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/22/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Anna Paola Muntoni (DISAT\, Polytechnic University of Turin\, Ital
y)
DTSTART:20230502T120000Z
DTEND:20230502T130000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/23
DESCRIPTION:Title: An approximate solution for the compressed sensing problem usi
ng statistical mechanics tool\nby Anna Paola Muntoni (DISAT\, Polytech
nic University of Turin\, Italy) as part of Seed Seminar of Mathematics an
d Physics\n\n\nAbstract\nMany interesting problems in fields ranging from
telecommunications to computational biology can be formalized in terms of
large underdetermined systems of linear equations with additional constrai
nts or regularizers. One of the most studied\, the compressed sensing (CS)
problem\, consists in finding the solution with the smallest number of no
n-zero components of a given system of linear equations.\n\nIn this talk\,
I will address the CS problem within a Bayesian inference framework where
the sparsity constraint is remapped into a singular prior distribution (c
alled Spike-and-Slab or Bernoulli–Gauss). A solution to the problem is a
ttempted through the computation of marginal distributions via Expectation
Propagation\, an iterative computational scheme originally developed in s
tatistical physics.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/23/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Joonas Turunen (Faculty of Mathematics\, University of Vienna\, Au
stria)
DTSTART:20230516T120000Z
DTEND:20230516T130000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/24
DESCRIPTION:Title: Statistical mechanics models on random maps of the disk and th
e half-plane\nby Joonas Turunen (Faculty of Mathematics\, University o
f Vienna\, Austria) as part of Seed Seminar of Mathematics and Physics\n\n
\nAbstract\nIn the main part of this talk\, which is mostly based on joint
works with Linxiao Chen\, we start from a purely combinatorial problem of
random planar triangulations of the disk coupled with the Ising model wit
h Dobrushin boundary conditions and at a fixed temperature (and without ex
ternal magnetic field). We identify rigorously a phase transition by analy
sing the critical behaviour of the partition functions of a large disk at
and around the critical temperature. Moreover\, we study the random geomet
ric implications of this in particular in a local limit when the disk peri
meter tends to infinity. At the critical temperature\, we also find some e
xplicit scaling limits of observables related to the interface lengths\, w
hich have interpretations in the continuum Liouville Quantum Gravity. The
two key techniques in use are singularity analysis of rational parametriza
tions of generating functions\, as well as the aforementioned exploration
process. At the end of the talk\, we will briefly discuss how this approac
h could be applied in further investigations of the Ising model and genera
lized to other statistical mechanics models on similar random lattices.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/24/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Ali Khezeli (Centre Inria de Paris\, France et Tarbiat Modares Uni
versity\, Teheran\, Iran)
DTSTART:20230530T120000Z
DTEND:20230530T130000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/25
DESCRIPTION:Title: Unimodular Random Measured Metric Spaces and Palm Theory on Th
em\nby Ali Khezeli (Centre Inria de Paris\, France et Tarbiat Modares
University\, Teheran\, Iran) as part of Seed Seminar of Mathematics and Ph
ysics\n\n\nAbstract\nIn this work\, we define the notion of unimodular ran
dom measured metric spaces as a common generalization of various other not
ions. This includes the discrete cases like unimodular graphs and stationa
ry point processes\, as well as the non-discrete cases like stationary ran
dom measures and the continuum metric spaces arising as scaling limits of
graphs. We provide various examples and prove many general results\; e.g.\
, on weak limits\, re-rooting invariance\, random walks\, ergodic decompos
ition\, amenability and balancing transport kernels. In addition\, we gene
ralize the Palm theory to point processes and random measures on a given u
nimodular space. This is useful for Palm calculations and also for reducin
g some problems to the discrete cases.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/25/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Gabriele Sicuro (King's College London\, United Kingdom)
DTSTART:20230606T120000Z
DTEND:20230606T130000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/26
DESCRIPTION:Title: Classification of fat-tailed clusters in high dimensions\n
by Gabriele Sicuro (King's College London\, United Kingdom) as part of See
d Seminar of Mathematics and Physics\n\n\nAbstract\nI will discuss the pro
blem of learning a mixture of two clouds of data points with generic centr
oids via empirical risk minimisation in the high dimensional regime\, unde
r the assumptions of generic convex loss and convex regularisation. Each c
loud of data points is obtained by sampling from a possibly uncountable su
perposition of Gaussian distributions\, whose variance has a generic proba
bility density ϱ. Our analysis covers therefore a large family of data di
stributions\, including the case of power-law-tailed distributions with no
covariance. We study the generalisation performance of the obtained estim
ator\, we analyse the role of regularisation and the dependence of the sep
arability transition on the distribution scale parameters.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/26/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Tom Hutchcroft (Department of Mathematics\, California Institute o
f Technology\, Pasadena\, USA)
DTSTART:20230627T120000Z
DTEND:20230627T130000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/27
DESCRIPTION:Title: Critical behaviour in long-range and hierarchical percolation<
/a>\nby Tom Hutchcroft (Department of Mathematics\, California Institute o
f Technology\, Pasadena\, USA) as part of Seed Seminar of Mathematics and
Physics\n\n\nAbstract\nStatistical mechanics models undergoing a phase tra
nsition often exhibit rich\, fractal-like behaviour at their critical poin
ts\, which are described in part by critical exponents – the indices gov
erning the power-law growth or decay of various quantities of interest. Th
ese exponents are expected to depend on the dimension but not on the micro
scopic details of the model such as the choice of lattice. After much prog
ress over the last thirty years we now understand two-dimensional and high
-dimensional models rather well\, but intermediate dimensions such as thre
e remain mysterious. I will discuss these issues in the context of long-ra
nge and hierarchical percolation\, and in particular how we can now comput
e some critical exponents for the hierarchical model in all dimensions.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/27/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Aleix Gimenez-Grau (Institut des Hautes Études Scientifiques\, Bu
res-sur-Yvette\, France)
DTSTART:20231031T130000Z
DTEND:20231031T140000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/28
DESCRIPTION:Title: Scale without Conformal Invariance in Dipolar Ferromagnets
\nby Aleix Gimenez-Grau (Institut des Hautes Études Scientifiques\, Bures
-sur-Yvette\, France) as part of Seed Seminar of Mathematics and Physics\n
\n\nAbstract\nIt is a common belief that isotropic ferromagnets\, when tun
ed to their critical temperature\, can be described by an RG fixed point i
n the universality class of the Heisenberg model. Although this is often a
good approximation\, ferromagnets always contain dipolar interactions\, w
hich lead to a different fixed point called the dipolar fixed point. In th
is talk\, we point out that the dipolar fixed point is a field theory whic
h is scale but not conformal invariant. We show that this dipolar field th
eory enjoys a shift symmetry\, which is responsible for the lack of confor
mal invariance and explains the non-renormalization of the virial current.
In fact\, we observe that shift symmetry is the mechanism behind all othe
r currently known models which are scale but not conformal invariant.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/28/
END:VEVENT
BEGIN:VEVENT
SUMMARY:David Pechersky (University of Toronto\, Canada)
DTSTART:20231114T150000Z
DTEND:20231114T160000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/29
DESCRIPTION:Title: Orthodiagonal maps\, tilings of rectangles and their convergen
ce to the Riemann map\nby David Pechersky (University of Toronto\, Can
ada) as part of Seed Seminar of Mathematics and Physics\n\n\nAbstract\nDis
crete complex analysis is the study of discrete holomorphic functions. The
se are functions defined on graphs embedded in the plane that satisfy some
discrete analogue of the Cauchy-Riemann equations. While the subject is c
lassical\, it has seen a resurgence in the past 20-30 years with the work
of Kenyon\, Mercat\, Smirnov\, and many others demonstrating the power of
discrete complex analysis as a tool for understanding 2D statistical physi
cs at criticality.\n\nIn this talk\, we’ll discuss how discrete complex
analysis can be applied to solve a purely deterministic problem for a very
general class of discretizations of 2D space accommodating a notion of di
screte complex analysis.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/29/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Giuseppe Di Giulio (University of Würzburg\, Germany)
DTSTART:20231128T130000Z
DTEND:20231128T140000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/30
DESCRIPTION:Title: Charged moments and symmetry-resolved entanglement in two-dime
nsional free conformal field theories\nby Giuseppe Di Giulio (Universi
ty of Würzburg\, Germany) as part of Seed Seminar of Mathematics and Phys
ics\n\n\nAbstract\nRecently\, there has been an intense research activity
on the interplay between symmetries and entanglement in many-body quantum
systems\, exploiting the block-diagonal structure of the reduced density m
atrix (RDM) in each charge sector. This talk aims to present results on th
e symmetry resolution of the entanglement in two-dimensional conformal fie
ld theories. In this context\, helpful quantities are the charged moments
and their generalization to multi-charged moments\, which are propedeutic
to the computation of symmetry-resolved entanglement entropies and mutual
information. These quantities can be seen as partition functions on multi-
sheeted Riemann surfaces and can be computed through suitable correlation
functions. I will present their computation for a massless Dirac field the
ory and a massless compact boson. In the former case\, the calculation is
reduced to correlation functions of vertex operators on the complex plane.
I will discuss why this method cannot be applied in the latter example\,
thus making necessary computing correlation functions on surfaces with arb
itrary genus.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/30/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Baptiste Cerclé (École Polytechnique Fédérale de Lausanne\, La
usanne\, Switzerland)
DTSTART:20231212T130000Z
DTEND:20231212T140000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/31
DESCRIPTION:Title: A probabilistic approach to Toda Conformal Field Theories\
nby Baptiste Cerclé (École Polytechnique Fédérale de Lausanne\, Lausan
ne\, Switzerland) as part of Seed Seminar of Mathematics and Physics\n\n\n
Abstract\nToda conformal field theories form a family of two-dimensional q
uantum field theories initially introduced in the physics literature. They
are natural generalizations of Liouville theory that enjoy\, in addition
to conformal invariance\, an enhanced level of symmetry encoded by W-algeb
ras.\n\nIn this presentation we will explain how one can study these theor
ies from a mathematically rigorous perspective. For this purpose we will d
escribe a probabilistic framework designed to make sense of these models a
nd provide some insight on how the introduction of this framework can help
to understand the model.\n\nTo be more specific\, we will prove ---we wil
l not enter into much details but rather try to convey the main ideas--- t
hat one can compute some basic correlation functions of the theory based o
n probabilistic tools. Along the proof of this statement we will shed ligh
t on some unexpected interplays between probability theory and conformal f
ield theory such as a generalized Brownian path decomposition.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/31/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Cristina Toninelli (CEREMADE - Université Paris Dauphine)
DTSTART:20240117T123000Z
DTEND:20240117T133000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/33
DESCRIPTION:Title: Bootstrap percolation and kinetically constrained models: univ
ersality results\nby Cristina Toninelli (CEREMADE - Université Paris
Dauphine) as part of Seed Seminar of Mathematics and Physics\n\nLecture he
ld in Maryam Mirzakhani (a.k.a. Salle 201 on 2nd floor)\, Institut Henri P
oincaré.\n\nAbstract\nRecent years have seen a great deal of progress in
understanding the behavior of bootstrap percolation (BP) models\, a partic
ular class of monotone cellular automata. In the initial configuration sit
es are occupied with probability p. The evolution of BP occurs at discrete
times: empty sites stay empty and occupied sites are emptied iff a certai
n model dependent neighborhood is already empty. In the Euclidean lattice
there is now a complete understanding of the large time evolution with a u
niversality picture for the critical behavior. Much less is known for thei
r non-monotone stochastic counterpart\, namely kinetically constrained mod
els (KCM). In KCM each vertex is updated independently at rate p (respecti
vely 1-p) to occupied (respectively empty) iff it could be emptied in the
next step by the bootstrap model. In the last two decades KCM have been t
he subject of intensive research both in physics and mathematics literatur
e. The main motivation is that\, for certain choices of the constraints\,
when p goes to zero KCM display some of the most striking features of the
liquid/glass transition. Indeed\, they were originally introduced in the 8
0's to support the free volume theories and later on used as the simplest
lattice models reproducing the dynamical facilitation scenario. In this se
minar I will discuss some recent rigorous results on the characteristic ti
me scales of KCM as p goes to zero as well as the connection with the cri
tical behavior of the corresponding BP models.\n\nPart of the kick-off eve
nt of the seminar's winter 2024 thematic trimester "From discrete models t
o condensed matter"\, at IHP (Paris). To attend in-person\, free but manda
tory registration here.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/33/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Pierre Le Bris (IHES - Université Paris-Saclay)
DTSTART:20240117T140000Z
DTEND:20240117T150000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/34
DESCRIPTION:Title: Proving Propagation of Chaos and Mean-field Limits\nby Pie
rre Le Bris (IHES - Université Paris-Saclay) as part of Seed Seminar of M
athematics and Physics\n\nLecture held in Maryam Mirzakhani (a.k.a. Salle
201 on 2nd floor)\, Institut Henri Poincaré.\n\nAbstract\nConsider a syst
em of $N$ particles\, described via a system of Stochastic Differential Eq
uations (SDEs)\, interacting in a mean field way. We are interested in the
limit\, as $N$ goes to infinity\, of this particle system\, and try to de
rive from a microscopic point of view (i.e. particle dynamics) a mesoscopi
c point of view (i.e. a statistical description of the system). The notion
of propagation of chaos refers to the phenomenon according to which\, as
the number of particles $N$ grows\, two given particles become « more and
more » statistically independent.\n\nThe aim of this talk is to discuss
more or less recent methods to prove this phenomenon for different types o
f particle systems\, notably in singular Riesz-type interaction\, with ide
as ranging from Probability theory to analysis of Partial Differential Equ
ations (PDEs). We focus in particular on quantitative and uniform in time
propagation of chaos.\n\nThis talk is based on joint works with A. Guillin
(université Clermont-Auvergne) et P. Monmarché (Sorbonne Université).\
n\nPart of the kick-off event of the seminar's winter 2024 thematic trimes
ter "From discrete models to condensed matter"\, at IHP (Paris). To attend
in-person\, free but mandatory registration here.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/34/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Anna Ritz-Zwilling (LPTMC - Sorbonne Université)
DTSTART:20240117T153000Z
DTEND:20240117T163000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/35
DESCRIPTION:Title: Partition function for string-net models\nby Anna Ritz-Zwi
lling (LPTMC - Sorbonne Université) as part of Seed Seminar of Mathematic
s and Physics\n\nLecture held in Maryam Mirzakhani (a.k.a. Salle 201 on 2n
d floor)\, Institut Henri Poincaré.\n\nAbstract\nThe string-net models we
re introduced by Levin and Wen (1) as exactly solvable models of topologic
al order in two dimensions. The latter appears in strongly interacting or
frustrated systems and is characterized by the presence of point-like exc
itations\, called anyons\, with exotic (i.e. neither fermionic nor bosonic
) exchange statistics. Built from a unitary fusion category\, the string-n
et models realize a topological order corresponding to the Drinfeld center
of the category. The energy spectrum of these models is trivial but the d
egeneracies are not. In particular\, they depend on the genus of the surfa
ce on which the model is defined. After introducing the models\, I will sh
ow how to compute these degeneracies and obtain the exact partition functi
on of these models\, opening the way to their study at finite temperature
(2\, 3).\n\n(1) M. A. Levin and X.-G. Wen\, Phys. Rev. B 71\, 045110 (20
05)\n\n(2) J. Vidal\, Phys. Rev. B 105\, L041110 (2020)\n\n(3) A. Ritz-Z
willing\, J.-N. Fuchs\, J. Vidal\, S. H. Simon\, https://arxiv.org/abs/230
9.00343\n\nPart of the kick-off event of the seminar's winter 2024 themati
c trimester "From discrete models to condensed matter"\, at IHP (Paris). T
o attend in-person\, free but mandatory registration here.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/35/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Haina Wang (Princeton University\, Princeton\, New Jersey\, USA)
DTSTART:20240130T140000Z
DTEND:20240130T150000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/36
DESCRIPTION:Title: Inverse Statistical Mechanics: Inferring Interactions from Mat
erials’ Spectra\nby Haina Wang (Princeton University\, Princeton\, N
ew Jersey\, USA) as part of Seed Seminar of Mathematics and Physics\n\n\nA
bstract\nThe inverse problem in statistical mechanics aims to find microsc
opic structures or interactions that correspond to macroscopic properties.
In my talk\, I will review some challenges for common methods to extract
effective interactions from the pair correlation function $g_2(r)$ [or equ
ivalently\, the structure factor $S(k)$] of many-body systems\, such as th
eir effective ambiguity of solutions despite a uniqueness theorem. Next\,
I will introduce my work to overcome such challenges by developing an inve
rse methodology that is accurate\, efficient\, and robust to noise. This m
ethodology has enabled us to quantify the "nonequilibriumness" of many-bod
y systems\, study the structural degeneracy ("isospectral") problem\, and
probe the realizability of prescribed pair correlation functions. We expec
t our approach to facilitate the design of self-assembly of materials with
desired optical and transport properties. Finally\, I will comment on how
inverse statistical mechanics can be extended to active-matter systems an
d how the recent development of stochastic automatic differentiation may b
e applied to devise more efficient inverse algorithms.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/36/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Gabriel Cuomo (Department of Physics\, Princeton University\, Prin
ceton\, New Jersey\, USA)
DTSTART:20240213T130000Z
DTEND:20240213T140000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/37
DESCRIPTION:Title: Spontaneous symmetry breaking on surface defects\nby Gabri
el Cuomo (Department of Physics\, Princeton University\, Princeton\, New J
ersey\, USA) as part of Seed Seminar of Mathematics and Physics\n\n\nAbstr
act\nColeman’s theorem states that continuous internal symmetries cannot
be spontaneously broken in two-dimensional quantum field theories (QFTs).
I will discuss under which conditions a similar result holds for two-dime
nsional defects in CFTs invariant under a continuous symmetry group. I wil
l argue that spontaneous symmetry breaking is only possible for exotic RG
flows\, that do not terminate at a fixed point. I will present examples an
d describe a generic defect universality class\, formerly found by Metlits
ki for boundaries in the O(N) model\, where correlation functions decay lo
garithmically at large distances.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/37/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Chiara Franceschini (University of Modena and Reggio Emilia\, Mode
na\, Italy)
DTSTART:20240227T130000Z
DTEND:20240227T140000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/38
DESCRIPTION:Title: Interacting particles systems out of equilibrium\nby Chiar
a Franceschini (University of Modena and Reggio Emilia\, Modena\, Italy) a
s part of Seed Seminar of Mathematics and Physics\n\n\nAbstract\nIn this t
alk I plan to give an overview of a rich family of models that share sever
al aspects. In particular\, they are all related to each other by a common
underlying algebraic description based on Lie Algebras. It is interesting
to add boundary reservoirs to place the systems out of equilibrium and th
us study the non-equilibrium stationary measure.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/38/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Ngoc Nhi Nguyen (Department of Mathematics "Federigo Enriques"\, U
niversity of Milan\, Milano\, Italy)
DTSTART:20240312T123000Z
DTEND:20240312T133000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/39
DESCRIPTION:Title: Weyl laws for interacting particles\nby Ngoc Nhi Nguyen (D
epartment of Mathematics "Federigo Enriques"\, University of Milan\, Milan
o\, Italy) as part of Seed Seminar of Mathematics and Physics\n\n\nAbstrac
t\nThe known Weyl laws of Schrödinger operators provide asymptotics the g
round state density of systems of several non-interacting fermions submitt
ed to an external potential . We will discuss the corresponding version in
the case of repulsive interactions between these particles.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/39/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Jérémie Bouttier (IMJ - Sorbonne Université\, Paris\, France)
DTSTART:20240327T123000Z
DTEND:20240327T133000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/40
DESCRIPTION:Title: On the O(n) loop model on random maps\nby Jérémie Boutti
er (IMJ - Sorbonne Université\, Paris\, France) as part of Seed Seminar o
f Mathematics and Physics\n\nLecture held in Maryam Mirzakhani (a.k.a. Sal
le 201 on 2nd floor)\, Institut Henri Poincaré.\n\nAbstract\nMaps are dis
crete surfaces obtained by gluing polygons\, and form a natural model of r
andom geometry. Of particular interest is the study of their large-scale p
roperties\, which has been an active field of research for more than 25 ye
ars. A major open question is the geometry of maps which are "decorated" b
y a statistical physics model at a critical point. I will present some res
ults about a specific instance of such model\, namely the O(n) loop model
on random maps. Based on past and ongoing collaborations with G. Borot\, E
. Guitter\, B. Duplantier\, G. Miermont and J. Turunen.\n\nPart of the kic
k-off event of the seminar's spring 2024 thematic trimester on Int
egrable systems\, at IHP (Paris). To attend in-person\, free but
mandatory registration here.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/40/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Qianyu Hao (Section de Mathématiques - University of Geneva\, Swi
tzerland)
DTSTART:20240327T140000Z
DTEND:20240327T150000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/41
DESCRIPTION:Title: Abelianization of Virasoro conformal blocks at $c=1$\nby Q
ianyu Hao (Section de Mathématiques - University of Geneva\, Switzerland)
as part of Seed Seminar of Mathematics and Physics\n\nLecture held in Mar
yam Mirzakhani (a.k.a. Salle 201 on 2nd floor)\, Institut Henri Poincaré.
\n\nAbstract\nConformal blocks are essential objects to study in the 2d CF
Ts. They depend on the data of a vertex algebra $\\CV$\, a punctured Riema
nn surface $C$\, and possible decorations inserted at the punctures. The V
irasoro conformal blocks are very interesting since they have many connect
ions to other areas of math and physics. In particular\, some very importa
nt Virasoro conformal blocks at c=1 are also known to be tau functions of
some integrable system. I will describe a new way to construct Virasoro co
nformal blocks at $c=1$. This is closely related to the idea of nonabelian
ization in the study of $SL(N\,\\mathbb{C})$ connections by using $GL(1\,\
\mathbb{C})$ connection in the work of Gaiotto-Moore-Neitzke and Neitzke-H
ollands. I will talk about our work on relating the $c=1$ Virasoro conform
al blocks on $C$ to the "abelian" Heisenberg conformal blocks on a branche
d double cover of C. The main new idea in our work is the use of the spect
ral network on the surface $C$. The nonabelianization construction enables
us to study the harder to get Virasoro conformal blocks using the simpler
abelian objects. This is joint work in progress with Andrew Neitzke.\n\nP
art of the kick-off event of the seminar's spring 2024 thematic trimester
on Integrable systems\, at IHP (Paris). To attend in-pers
on\, free but mandatory registration here.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/41/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Claudia Fevola (Centre INRIA de Saclay\, Palaiseau\, France)
DTSTART:20240327T153000Z
DTEND:20240327T160000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/42
DESCRIPTION:Title: Computational Algebraic Geometry for Feynman Integrals and the
ir Singularities\nby Claudia Fevola (Centre INRIA de Saclay\, Palaisea
u\, France) as part of Seed Seminar of Mathematics and Physics\n\n\nAbstra
ct\nFeynman integrals play a central role in particle physics in the theor
y of scattering amplitudes. In this talk\, I will show some examples of ho
w the interplay between algebro-geometric methods and fundamental physics
problems leads to advances in both disciplines. In particular\, I will dis
cuss vector spaces associated with a family of generalized Euler integrals
and the study of their singular locus.\n\nPart of the kick-off event of t
he seminar's spring 2024 thematic trimester on Integrable systems<
/strong>\, at IHP (Paris). To attend in-person\, free but mandatory regist
ration her
e.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/42/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Catherine Wolfram (Department of Mathematics\, MIT\, Cambridge\, U
SA)
DTSTART:20240423T130000Z
DTEND:20240423T140000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/43
DESCRIPTION:Title: The dimer model in 3D\nby Catherine Wolfram (Department of
Mathematics\, MIT\, Cambridge\, USA) as part of Seed Seminar of Mathemati
cs and Physics\n\n\nAbstract\nA dimer tiling of $ \\mathbb{Z}^d $ is a col
lection of edges such that every vertex is covered exactly once. In 2000\,
Cohn\, Kenyon\, and Propp showed that 2D dimer tilings satisfy a large de
viations principle. In joint work with Nishant Chandgotia and Scott Sheffi
eld\, we prove an analogous large deviations principle for dimers in 3D. A
lot of the results for dimers in two dimensions use tools and exact formu
las (e.g. the height function representation of a tiling or the Kasteleyn
determinant formula) that are specific to dimension 2. I will explain how
to formulate the large deviations principle in 3D\, show simulations\, and
try to give some intuition for why three dimensions is different from two
. Time permitting\, I will explain some of the ways that we use a smaller
set of tools (e.g. Hall’s matching theorem or a double dimer swapping op
eration) in our arguments.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/43/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Niklas Affolter (Institute of Discrete Mathematics and Geometry\,
TU Wien\, Vienna\, Austria)
DTSTART:20240423T140000Z
DTEND:20240423T150000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/44
DESCRIPTION:Title: Discrete Integrability\, Dimers and Geometry\nby Niklas Af
folter (Institute of Discrete Mathematics and Geometry\, TU Wien\, Vienna\
, Austria) as part of Seed Seminar of Mathematics and Physics\n\n\nAbstrac
t\nWe'll begin by explaining "discrete integrability" in the sense of mult
i-dimensional consistency. Discrete integrability is quite literally about
the possibility to "integrate" discrete equations or discrete dynamics. T
he dimer model is about sampling perfect matchings on a graph\, where the
probability of each perfect matching is proportional to a product of edge-
weights. We will see that the dimer model is discretely integrable. Finall
y\, we consider discrete geometric maps\, to which we attach a dimer model
. The maps also turn out to be discretely integrable\, and the dimer parti
tion functions provide the invariants of (discrete) motions. Based on join
t work with Béatrice de Tilière\, Max Glick\, Paul Melotti\, Pasha Pylya
vskyy and Sanjay Ramassamy.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/44/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Julien Roussillon (Aalto University\, Finland)
DTSTART:20240509T080000Z
DTEND:20240509T090000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/45
DESCRIPTION:Title: Degenerate conformal blocks for the $W_3$ algebra at $c=2$ and
Specht polynomials\nby Julien Roussillon (Aalto University\, Finland)
as part of Seed Seminar of Mathematics and Physics\n\n\nAbstract\nIn this
first talk\, I will provide a gentle introduction to Conformal Field Theo
ry and conformal blocks in general\, and I will discuss the case where the
y satisfy a system of PDEs known as BPZ equations. Then\, I will focus on
a special case where the PDEs are third order\, and I will present new sol
utions in terms of the celebrated Specht polynomials. If time permits\, I
will describe a conjecture relating such solutions to scaling limits of pr
obabilities in the triple dimer model recently constructed by Kenyon and S
hi. This talk is based on joint work with Augustin Lafay.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/45/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Harini Desiraju (Mathematical Research Institute\, Sydney\, Austra
lia)
DTSTART:20240509T090000Z
DTEND:20240509T100000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/46
DESCRIPTION:Title: The correspondence between Painlevé equations and c=1 conform
al blocks\, and its generalisation\nby Harini Desiraju (Mathematical R
esearch Institute\, Sydney\, Australia) as part of Seed Seminar of Mathema
tics and Physics\n\n\nAbstract\nThis talk will start with an overview of t
he Painlevé/CFT correspondence that was initiated by the seminal paper of
Gamayun\, Iorgov\, Lisovyi. I will then motivate a generalisation of such
a correspondence using the probabilistic construction of conformal blocks
.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/46/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Victor Nador (IMPAN\, Cracow\, Poland)
DTSTART:20240529T120000Z
DTEND:20240529T130000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/47
DESCRIPTION:Title: Jack polynomials and b-deformed constellations\nby Victor
Nador (IMPAN\, Cracow\, Poland) as part of Seed Seminar of Mathematics and
Physics\n\n\nAbstract\nThe generating series of weighted maps and its gen
eralization to constellations both take a simple form using Schur function
s. Its extension to the non-oriented case admits a similar expression but
for a different family of symmetric functions\, the zonal polynomials. In
both cases\, the properties of these generating series can be studied from
a wide variety of viewpoints: representation theory\, combinatorial decom
position\, random matrices\, integrable hierarchies etc.. The Jack polynom
ial are a one parameter deformation\, called the b-deformation\, which int
erpolates between the orientable and non-oriented cases. However\, the b-d
eformation makes the study of the corresponding series more intricate as m
ost of the above tools have no counterpart in that framework.\n\nIn this t
alk\, I will present some of the difficulties arising when studying the b-
deformation\, especially from a combinatorial viewpoint. I will define the
b-deformed analogue of constellations introduced by Chapuy and Dolega and
I will show how in the particular cases\, we can still extract a countabl
e set of PDE analogous to the cut-and-join equation\, based on recent resu
lts obtained with V. Bonzom.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/47/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Houcine Ben Dali (IECL\, Université de Lorraine\, Nancy and IRIF\
, Université Paris-Cité\, France)
DTSTART:20240529T130000Z
DTEND:20240529T140000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/48
DESCRIPTION:Title: Differential equations for the series of hypermaps with contro
l on their full degree profile\nby Houcine Ben Dali (IECL\, Universit
é de Lorraine\, Nancy and IRIF\, Université Paris-Cité\, France) as par
t of Seed Seminar of Mathematics and Physics\n\n\nAbstract\nWe consider ge
nerating series of hypermaps with controlled degrees of vertices\, hypered
ges and faces. It is well known that under some particular specializations
\, these series satisfy the celebrated KP equations in the orientable case
\, and BKP equations in the non-orientable one. In this talk\, I present a
family of differential equations which characterizes the full generating
series of hypermaps.\n\nI will give a first proof which works for a one pa
rameter deformation of the series of hypermaps related to Jack polynomials
. This proof is based on a differential formula for Jack characters obtai
ned in a joint work with Maciej Dołęga. I will also present a combinator
ial proof for the orientable case.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/48/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Fabiana De Cesare (IHÉS)
DTSTART:20241120T093000Z
DTEND:20241120T103000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/49
DESCRIPTION:Title: Exploring confinement in Anti-de Sitter space\nby Fabiana
De Cesare (IHÉS) as part of Seed Seminar of Mathematics and Physics\n\n\n
Abstract\nAnti-de Sitter space acts as an infra-red cutoff for asymptotica
lly free theories\, allowing interpolation between a weakly-coupled small-
sized regime and a strongly-coupled flat-space regime. I will discuss this
interpolation in the context of Yang-Mills theories in AdS from the persp
ective of boundary conformal theories and its implications for the confine
ment/deconfinement transition. We find indications that at the transition
a singlet scalar operator becomes marginal\, destabilizing the deconfined
phase existing at a small size and leading to a confined phase that smooth
ly connects to flat space.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/49/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Nikolay Ebel (IHÉS)
DTSTART:20241120T110000Z
DTEND:20241120T120000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/50
DESCRIPTION:Title: Tensor Network Renormalization Group Maps and Their Fixed Poin
ts\nby Nikolay Ebel (IHÉS) as part of Seed Seminar of Mathematics and
Physics\n\n\nAbstract\nTensor network renormalization group (RG) is a pow
erful technique providing great control over the renormalization group flo
w both numerically and analytically. This talk will focus on the study of
fixed points of tensor network RG maps in the context of classical lattice
models (e.g.\, the Ising model). Studying fixed points allows one to retr
ieve information about phase transitions in a system\, which motivates thi
s research. I will first introduce basic tensor network concepts. Then\, I
will present some rigorous results about high- and low-temperature fixed
points of lattice spin models (based on arXiv:2107.11464\, 2210.06669\, an
d 2401.04229). Finally\, I will discuss the recent development that may gr
ant access to the critical fixed points of lattice systems (based on arXiv
:2408.10312).\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/50/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Nafiz Ishtiaque (IHÉS)
DTSTART:20241204T110000Z
DTEND:20241204T120000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/51
DESCRIPTION:Title: Kramers-Wannier Duality in Non-abelian Ising Models from SymTF
T\nby Nafiz Ishtiaque (IHÉS) as part of Seed Seminar of Mathematics a
nd Physics\n\n\nAbstract\nI will present a concrete construction of 2d Isi
ng partition functions on lattice\, with non-abelian (more generally non-i
nvertible) global symmetry. The construction realizes the Ising model as t
he boundary theory of a 3d symmetry topological field theory (SymTFT) with
specific boundary conditions. Suitable choices of boundary conditions cor
respond to going to different topological sectors of the global symmetry o
r gauging arbitrary non-anomalous subsymmetry. Electric-magnetic type dual
ity of the SymTFT results in dual descriptions of the Ising model that gen
eralizes the Kramers-Wannier duality of Z/2Z symmetric Ising models.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/51/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Francesco Russo (Ecole Polytechnique)
DTSTART:20241204T093000Z
DTEND:20241204T103000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/52
DESCRIPTION:Title: Partial wave decomposition in thermal conformal field theories
\nby Francesco Russo (Ecole Polytechnique) as part of Seed Seminar of
Mathematics and Physics\n\n\nAbstract\nThe conformal block expansion of co
rrelation functions is a fundamental tool in the bootstrap program. Block
computation can be related to a specific class of harmonic functions on th
e conformal group. We generalize this concept to the case of thermal confo
rmal field theories and compute one-point blocks for spinning representati
ons in three dimensions. Specifically\, we derive a universal Casimir equa
tion and solve it using recursion relations. Finally\, we use the blocks i
n several examples to explore some features of OPE coefficients.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/52/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Ioana Coman (IPMU)
DTSTART:20241218T110000Z
DTEND:20241218T120000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/54
DESCRIPTION:Title: Modularity and resurgence of topological 3-manifold invariants
\nby Ioana Coman (IPMU) as part of Seed Seminar of Mathematics and Phy
sics\n\n\nAbstract\nA type of BPS q-series\, proposed recently as a topolo
gical invariant which provides a non-perturbative completion of complex Ch
ern-Simons theory on closed 3-dimensional manifolds\, has mathematical def
initions based for example on 3D topology\, quantum groups and resurgence\
, and key properties their integrality and behaviour under surgery formula
e. These q-series invariants have displayed relations to vertex operator a
lgebras\, and structurally\, they have intriguing modular properties. Thei
r mathematical formulation is nevertheless quite constrained\, relying hea
vily on certain negative-definite conditions\, and much effort has been de
voted to extending this definition. This operation is called “going to t
he other side”\, with different interpretations from the physics\, verte
x algebra\, and 3D topology perspectives. I will discuss different approac
hes to this challenge\, in particular through modularity and resurgence\,
with implications for the related vertex operator algebras.\n\nonline\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/54/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Bertrand Duplantier (Institut de Physique Théorique\, CEA Saclay\
, Université Paris-Saclay)
DTSTART:20250212T123000Z
DTEND:20250212T133000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/55
DESCRIPTION:Title: Hamiltonian Paths on Random Planar Maps\nby Bertrand Dupla
ntier (Institut de Physique Théorique\, CEA Saclay\, Université Paris-Sa
clay) as part of Seed Seminar of Mathematics and Physics\n\nLecture held i
n Amphi Choquet-Bruhat (batiment Perrin)\, Institut Henri Poincaré\, Pari
s.\n\nAbstract\nHamiltonian paths are self-avoiding random walks that visi
t all sites of a given lattice. We consider various configuration exponent
s of Hamiltonian walks drawn on random planar maps. Estimates from exact e
numerations are compared with predictions based on the Knizhnik-Polyakov-Z
amolodchikov (KPZ) relations\, as applied to exponents on the regular hexa
gonal lattice. Astonishingly\, when the maps are bipartite\, a naive use o
f KPZ does not reproduce all the measured exponents\, but an Ansatz may po
ssibly account for the observed discrepancies. We further study Hamiltonia
n cycles on various families of bipartite planar maps\, which fall into tw
o universality classes\, with respective central charges c = -1 or c = -2.
The first group comprises maps of fixed vertex valency p larger than 3\,
whereas the second group involves maps with mixed vertex valencies\, as we
ll as a so-called rigid case. For each class\, a universal configuration e
xponent and a novel critical exponent associated with long-distance contac
ts along a Hamiltonian cycle are predicted from KPZ and the corresponding
exponent on regular (hexagonal or square) lattices. This time\, the KPZ pr
edictions are numerically confirmed by exact enumeration results for p-reg
ular maps\, with p = 3\, 4\, 5\, 6\, 7\, and for maps with mixed valencies
(2\,3) and (2\,4). The scaling limit of fully-packed systems thus poses i
ntriguing unresolved questions from both the Liouville Quantum Gravity and
the Schramm-Loewner Evolution perspectives. Based on joint works with Ph.
Di Francesco\, O. Golinelli and E. Guitter.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/55/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Yizheng Yuan (Statistical Laboratory\, Cambridge University\, UK)
DTSTART:20250212T140000Z
DTEND:20250212T150000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/56
DESCRIPTION:Title: The chemical distance metric for non-simple CLE\nby Yizhen
g Yuan (Statistical Laboratory\, Cambridge University\, UK) as part of See
d Seminar of Mathematics and Physics\n\nLecture held in Amphi Choquet-Bruh
at (batiment Perrin)\, Institut Henri Poincaré\, Paris.\n\nAbstract\nWe c
onstruct the continuum analogue of the chemical distance metric in\nlattic
e models such as percolation. The chemical distance metric is the\ngraph d
istance induced by the percolation clusters. It is known that for\ncritica
l percolation\, the lengths have non-trivial scaling behaviour\,\nhowever
it is very difficult to find the exact scaling exponent. (This\nis one of
the questions from Schramm's ICM 2006 article that remains\nunsolved.)\n\n
In a joint work with Valeria Ambrosio and Jason Miller\, we construct a\nc
hemical distance metric on the CLE gasket for each $\\kappa \\in ]4\,8[$.
We\nshow that it is unique metric that is geodesic\, Markovian\, and\nconf
ormally covariant. The characterisation is reminiscent of the LQG\nmetric\
, but our objects behave very differently\, and hence our\ntechniques also
differ significantly from those used in LQG. For\n$\\kappa=6$\, we conjec
ture that our random metric space is the scaling\nlimit of critical percol
ation.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/56/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Léonie Papon (Durham University\, UK)
DTSTART:20250212T153000Z
DTEND:20250212T163000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/57
DESCRIPTION:Title: Interface scaling limit for the critical planar Ising model pe
rturbed by a magnetic field\nby Léonie Papon (Durham University\, UK)
as part of Seed Seminar of Mathematics and Physics\n\nLecture held in Amp
hi Choquet-Bruhat (batiment Perrin)\, Institut Henri Poincaré\, Paris.\n\
nAbstract\nIn this talk\, I will consider the interface separating +1 and
-1 spins in the critical planar Ising model with Dobrushin boundary condit
ions perturbed by an external magnetic field. I will prove that this inter
face has a scaling limit. This result holds when the Ising model is define
d on a bounded and simply connected subgraph of $\\delta\\mathbb{Z}^2$\, w
ith $\\delta > 0$. I will show that if the scaling of the external field i
s of order $\\delta^{15/8}$\, then\, as $\\delta \\to 0$\, the interface c
onverges in law to a random curve whose law is conformally covariant and a
bsolutely continuous with respect to $\\text{SLE}_3$. This limiting law is
a massive version of $\\text{SLE}_3$ in the sense of Makarov and Smirnov
and I will give an explicit expression for its Radon-Nikodym derivative wi
th respect to $\\text{SLE}_3$. I will also prove that if the scaling of th
e external field is of order $\\delta^{15/8}g(\\delta)$ with $g(\\delta) \
\to 0$\, then the interface converges in law to $\\text{SLE}_3$. In contra
st\, I will show that if the scaling of the external field is of order $\\
delta^{15/8}f(\\delta)$ with $f(\\delta) \\to \\infty$\, then the interfac
e degenerates to a boundary arc.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/57/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Paul Roux (École Normale Supérieure\, Paris\, France)
DTSTART:20250226T093000Z
DTEND:20250226T103000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/58
DESCRIPTION:Title: Combinatorial maps in critical loop model\nby Paul Roux (
École Normale Supérieure\, Paris\, France) as part of Seed Seminar of Ma
thematics and Physics\n\nLecture held in Amphithéâtre Léon Motchane\, I
HÉS.\n\nAbstract\nLoop models are a class of statistical lattice models w
hose correlation functions can be interpreted geometrically\, as sums over
configurations of non-intersecting loops. In the critical limit\, the obs
ervables of these models are described by a Conformal Field Theory (CFT)\,
which is believed to be exactly solvable. In this talk\, we will shortly
review what are loop models and present recent results showing that their
correlation functions are related to combinatorial objects called combinat
orial maps. Then\, we will relate the counting of certain maps on the toru
s to particular classes of maps on the sphere\, and explain the CFT interp
retation of this mapping.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/58/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Alicia Castro (Laboratoire Bordelais de Recherche en Informatique
(LaBRI)\, France)
DTSTART:20250226T110000Z
DTEND:20250226T120000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/59
DESCRIPTION:Title: Critical JT Gravity\nby Alicia Castro (Laboratoire Bordela
is de Recherche en Informatique (LaBRI)\, France) as part of Seed Seminar
of Mathematics and Physics\n\nLecture held in Amphithéâtre Léon Motchan
e\, IHÉS.\n\nAbstract\nIn this talk\, I will present JT gravity\, a model
of two-dimensional quantum gravity on constant negatively curved spacetim
es\, as a model of random hyperbolic surfaces. By studying the generating
function of volumes of random hyperbolic surfaces with defects\, i.e. weig
hted geodesic boundaries\, we explore critical regimes where the surfaces
develop macroscopic holes. This is reminiscent of the $O(N)$ model for ran
dom maps. We analyse the impact of this critical behavior on the density o
f states of the theory at the boundary\, and we present a family of models
that interpolate between systems with $\\sqrt{E}$ and $E^{3/2}$\, which a
re commonly found in models of JT Gravity coupled to dynamical end-of-the-
world and FZZT branes.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/59/
END:VEVENT
BEGIN:VEVENT
SUMMARY:William Da Silva (University of Vienna\, Austria)
DTSTART:20250312T093000Z
DTEND:20250312T103000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/60
DESCRIPTION:Title: The scaling limit of the volume of loop-O(n) quadrangulations<
/a>\nby William Da Silva (University of Vienna\, Austria) as part of Seed
Seminar of Mathematics and Physics\n\nLecture held in Amphithéâtre Léon
Motchane.\n\nAbstract\nWe study the volume of rigid loop-O(n) quadrangula
tions with a boundary of length 2p in the critical non-generic regime. We
prove that\, as the half-perimeter p goes to infinity\, the volume scales
in distribution to an explicit random variable. This limiting random varia
ble is described in terms of the multiplicative cascades of Chen\, Curien
and Maillard\, or alternatively (in the dilute case) as the law of the are
a of a suitable unit-boundary quantum disc\, as determined by Ang and Gwyn
ne. Our arguments go through a classification of the map into several regi
ons\, where we rule out the contribution of bad regions to be left with a
tractable portion of the map. One key observable for this classification i
s a Markov chain which explores the nested loops around a size-biased vert
ex pick in the map\, making explicit the spinal structure of the discrete
multiplicative cascade. This talk is based on joint work with Élie Aïdé
kon and XingJian Hu (Fudan University).\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/60/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Vlad Margarint (University of North Carolina Charlotte\, USA)
DTSTART:20250312T110000Z
DTEND:20250312T120000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/61
DESCRIPTION:Title: A bridge between Random Matrix Theory and Schramm-Loewner Evol
utions\nby Vlad Margarint (University of North Carolina Charlotte\, US
A) as part of Seed Seminar of Mathematics and Physics\n\nLecture held in A
mphithéâtre Léon Motchane.\n\nAbstract\nI will describe a newly introdu
ced toolbox that connects two areas of Probability Theory: Schramm-Loewner
Evolutions (SLE) and Random Matrix Theory. This machinery opens new avenu
es of research that allow the use of techniques from one field to another.
One aspect of this research direction is centered in an interacting parti
cle systems model\, namely the Dyson Brownian motion. In the first part of
the talk\, I will introduce basic ideas of SLE theory\, then I will descr
ibe the connection with Random Matrix Theory via a first application of ou
r method. I will finish the talk with some open problems that emerge using
this newly introduced toolbox. This is a joint work with A. Campbell and
K. Luh.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/61/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Lorenzo Dello Schiavo (Università degli Studi di Roma "Tor Vergat
a")
DTSTART:20250326T093000Z
DTEND:20250326T103000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/62
DESCRIPTION:Title: Conformally invariant random fields\, quantum Liouville measur
es\, and random Paneitz operators on Riemannian manifolds of even dimensio
n\nby Lorenzo Dello Schiavo (Università degli Studi di Roma "Tor Verg
ata") as part of Seed Seminar of Mathematics and Physics\n\n\nAbstract\nOn
large classes of closed even-dimensional Riemannian manifolds M\, we cons
truct and study the Copolyharmonic Gaussian Field\, i.e. a conformally inv
ariant log-correlated Gaussian field of distributions on M. This random fi
eld is defined as the unique centered Gaussian field with covariance kerne
l given as the resolvent kernel of Graham—Jenne—Mason—Sparling (GJMS
) operators of maximal order. The corresponding Gaussian Multiplicative Ch
aos is a generalization to the 2m-dimensional case of the celebrated Liouv
ille Quantum Gravity measure in dimension two. We study the associated Lio
uville Brownian motion and random GJMS operator\, the higher-dimensional a
nalogues of the 2d Liouville Brownian Motion and of the random Laplacian.
Finally\, we study the Polyakov–Liouville measure on the space of distri
butions on M induced by the copolyharmonic Gaussian field\, providing expl
icit conditions for its finiteness and computing the conformal anomaly.\nJ
. London Math. Soc. (2) 2024:110\, 1-80\, joint work with Ronan Herry\, Ev
a Kopfer\, Karl-Theodor Sturm.\n\nOnly online\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/62/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Liam Hughes
DTSTART:20250326T110000Z
DTEND:20250326T120000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/63
DESCRIPTION:Title: Embeddability of Liouville quantum gravity metrics\nby Lia
m Hughes as part of Seed Seminar of Mathematics and Physics\n\n\nAbstract\
nIntroduced by Polyakov in the 1980s\, Liouville quantum gravity (LQG) is
in some sense the canonical model of a random fractal Riemannian surface.
LQG can be defined as a path integral over fields corresponding to the Lio
uville action\, or equivalently as a random metric measure space that turn
s out to describe the scaling limit of a host of two-dimensional discrete
objects. In particular\, certain discrete conformal embeddings of random p
lanar maps converge to canonical (up to conformal reparametrization) embed
dings of LQG surfaces into 2D Euclidean space. Though one might expect the
se metric embeddings to retain some vestige of conformality\, in fact no e
mbedding of an LQG surface into R^n can be quasisymmetric. This generalize
s a result of Troscheit in the special case of sqrt(8/3)-LQG (correspondin
g to uniform random planar maps). Time permitting\, I will also discuss fu
ture directions in the study of metric embeddability for LQG.\n\nOnly onli
ne\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/63/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Nicolas Curien (LMO\, Université Paris-Saclay)
DTSTART:20250425T080000Z
DTEND:20250425T090000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/64
DESCRIPTION:Title: Universality of fully parked trees and catalytic equations
\nby Nicolas Curien (LMO\, Université Paris-Saclay) as part of Seed Semin
ar of Mathematics and Physics\n\nLecture held in Institut Pascal.\n\nAbstr
act\nWe show that critical parking trees conditioned to be fully parked co
nverge in the scaling limits towards the Brownian growth-fragmentation tre
e\, a self-similar Markov tree different from Aldous’ Brownian tree. As
a by-product of our study\, we prove that positive non-linear functional e
quations involving a catalytic variable display a universal polynomial exp
onent 5/2 at their singularity\, confirming a conjecture by Chapuy\, Schae
ffer and Drmota & Hainzl. Compared to previous analytical works on the sub
ject\, our approach is probabilistic and exploits an underlying random wal
k hidden in the random tree model. Joint work with Alice Contat.\n\nThis t
alk is part of the "SEED Annual Workshop". To attend this event please reg
ister at https://indico.ijclab.in2p3.fr/event/11715/\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/64/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Boris Pioline (LPTHE\, Sorbonne Université))
DTSTART:20250425T091500Z
DTEND:20250425T101500Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/65
DESCRIPTION:Title: Modularity of enumerative invariants on Calabi-Yau threefolds<
/a>\nby Boris Pioline (LPTHE\, Sorbonne Université)) as part of Seed Semi
nar of Mathematics and Physics\n\nLecture held in Institut Pascal.\n\nAbst
ract\nModularity of enumerative invariants on Calabi-Yau threefolds\n Apr
25\, 2025\, 11:15 AM\n 1h\n small Amphitheater\nSpeaker\n Boris Pioline
(LPTHE\, Sorbonne Université)\nDescription\nOnce put into suitable genera
ting series\, various enumerative invariants on Calabi-Yau threefolds are
expected to possess modular properties\, allowing to determine them unique
ly from a few data points and giving powerful control on their asymptotic
growth. This includes Gromov-Witten invariants in presence of a genus one
fibration\, Noether-Lefschetz invariants in presence of a K3 fibration\, a
s well as Donalson-Thomas invariants supported on divisors (without requir
ing any particular fibration). While modularity has a clear mathematical o
rigin in the first two cases\, it is more mysterious in the last case\, co
rresponding physically to BPS indices counting D4-D2-D0 black holes. I wil
l review recent progress in testing the modularity (or more generally mock
modularity) of D4-D2-D0 indices in one-parameter Calabi-Yau threefolds su
ch as the quintic threefold\, and in leveraging these results to compute G
opakumar-Vafa invariants at higher genus than hitherto possible. Based on
work in collaboration with Sergey Alexandrov\, Soheyla Feyzbakhsh\, Albrec
ht Klemm and Thorsten Schimannek.\n\nThis talk is part of the "SEED Annual
Workshop". To attend this event please register at https://indico.ijclab.
in2p3.fr/event/11715/\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/65/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Clément Delcamp (IHÉS)
DTSTART:20250425T120000Z
DTEND:20250425T130000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/66
DESCRIPTION:Title: Entanglement and renormalisation of spin systems in the genera
lised Landau paradigm\nby Clément Delcamp (IHÉS) as part of Seed Sem
inar of Mathematics and Physics\n\nLecture held in Institut Pascal.\n\nAbs
tract\nInvoking results from topological quantum field theory\, I will dem
onstrate that for every spin system representing a symmetric gapped phase\
, one can find a dual physical system whose dual symmetry is spontaneously
broken. I will argue that this result has strong implications for the cla
ssical simulation of spin systems using variational tensor network methods
\, as this dual physical system minimises both the entanglement entropy an
d the required number of variational parameters. The applicability of this
method will be demonstrated by introducing a generalised Density Matrix R
enormalisation Group algorithm.\n\nThis talk is part of the "SEED Annual W
orkshop". To attend this event please register at https://indico.ijclab.in
2p3.fr/event/11715/\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/66/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Balt Van Rees (CPhT\, École polytechnique)
DTSTART:20250425T131500Z
DTEND:20250425T141500Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/67
DESCRIPTION:Title: Theorems for the modular and lightcone bootstrap\nby Balt
Van Rees (CPhT\, École polytechnique) as part of Seed Seminar of Mathemat
ics and Physics\n\nLecture held in Institut Pascal.\n\nAbstract\nWe consid
er the implications of modular invariance for the spectrum of two-dimensio
nal CFTs. For states with high energy this question was analyzed at a qual
itative level by Cardy in 1986\, but rigorous statements were almost entir
ely absent until the analysis (based on Tauberian theorems) by Mukhametzha
nov and Zhiboedeov in 2019. In this talk we consider states with a very la
rge spin\, for which we show that it is possible to obtain much stronger r
igorous results. Using complex analysis we in particular demonstrate that
the spectrum of twists necessarily becomes dense for every large spin. We
analyze the size of the subleading corrections\, which will allow us to es
timate how rapidly the maximal spacing between operators goes to zero. An
entirely analogous procedure can be applied to four-point functions of ide
ntical operators in CFTs with a twist gap.\n\nTalk based on work in progre
ss with Sridip Pal and Jiaxin Qiao.\n\nThis talk is part of the "SEED Annu
al Workshop". To attend this event please register at https://indico.ijcla
b.in2p3.fr/event/11715/\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/67/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Stavros Garoufalidis (ICM-SUSTech\, and IHÉS)
DTSTART:20250425T143000Z
DTEND:20250425T153000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/68
DESCRIPTION:Title: What can the gluing equation matrices tell us about a 3-manifo
ld?\nby Stavros Garoufalidis (ICM-SUSTech\, and IHÉS) as part of Seed
Seminar of Mathematics and Physics\n\nLecture held in Institut Pascal.\nA
bstract: TBA\n\nThis talk is part of the "SEED Annual Workshop". To attend
this event please register at https://indico.ijclab.in2p3.fr/event/11715/
\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/68/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Ellen Saada (CNRS & MAP5\, Université Paris-Cité\, France)
DTSTART:20250604T113000Z
DTEND:20250604T123000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/69
DESCRIPTION:Title: The two-lane exclusion process\nby Ellen Saada (CNRS & MAP
5\, Université Paris-Cité\, France) as part of Seed Seminar of Mathemati
cs and Physics\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/69/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Pierluigi Niro (SISSA\, Trieste\, Italy)
DTSTART:20250604T130000Z
DTEND:20250604T140000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/70
DESCRIPTION:Title: Symmetry breaking in 3d QED\nby Pierluigi Niro (SISSA\, Tr
ieste\, Italy) as part of Seed Seminar of Mathematics and Physics\n\nAbstr
act: TBA\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/70/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Lucas D'Alimonte (LPSM\, Sorbonne Université\, Paris\, France)
DTSTART:20250604T143000Z
DTEND:20250604T153000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/71
DESCRIPTION:Title: Ornstein—Zernike theory for the near-critical planar random
cluster model\nby Lucas D'Alimonte (LPSM\, Sorbonne Université\, Pari
s\, France) as part of Seed Seminar of Mathematics and Physics\n\nAbstract
: TBA\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/71/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Xia Jiaming (IHES)
DTSTART:20250611T100000Z
DTEND:20250611T110000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/72
DESCRIPTION:Title: Extract one-arm exponent in FK models from the convergence of
height functions to GFF\nby Xia Jiaming (IHES) as part of Seed Seminar
of Mathematics and Physics\n\nLecture held in IHES\, Amphithéâtre Léon
Motchane.\n\nAbstract\nWe consider FK models with q in [0\,4] on the squa
re lattice and the whole plane. We assume the convergence of height functi
ons to GFF and in particular we assume that we know the variance σ2 of th
e GFF. Then\, we sketch an approach to get the exponent α1 describing the
probability of having a primal crossing of an annulus. The basis for this
approach is the BKW coupling relating the height function to the interfac
e loops of FK. We show that by choosing appropriate test functions (viewed
as placing charges on the plane)\, we can get relations between σ2\, α1
\, and a factor accounting for local concentration of small interface loop
s.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/72/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Orphée Collin (LPSM\, Université Paris-Cité\, France)
DTSTART:20250618T083000Z
DTEND:20250618T093000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/73
DESCRIPTION:Title: The Random Field Ising Chain in the case of centered disorder<
/a>\nby Orphée Collin (LPSM\, Université Paris-Cité\, France) as part o
f Seed Seminar of Mathematics and Physics\n\nLecture held in IHES\, Amphit
héâtre Léon Motchane.\n\nAbstract\nOur understanding of the behaviors a
ppearing in statistical physics has been built firstly on the well-known I
sing Model. Here\, we will consider a disordered version of the one-dimens
ional Ising model: we will present and study the ferromagnetic Ising model
on a line graph interacting with an external magnetic field\, sampled fro
m an i.i.d. distribution. We will be interested in the regime where the in
tensity of the disorder is fixed and the spin-spin interaction goes to inf
inity.\n\nWe will also introduce a continuous version of the model\, which
naturally arises from a weak disorder limit. For this continuous model\,
various quantities (such as the free energy) can be computed explicitely\,
thus yielding precise information on the typical configurations of the sy
stem.\n\nThe free energy of the discrete model can easily be expressed as
the Lyapunov exponent of a random product of 2x2 matrices\, which we estim
ate using Furstenberg’s theory: we will present recent results on the as
ymptotics of the free energy\, in the regime we consider.\n\nFurthermore\,
in both the discrete and the continuous models\, we will characterize the
behaviour of the system at the level of configurations. In agreement with
predictions in the physics literature\, we will show that the configurati
ons are typically close to one given configuration\, determined by the env
ironment (the external field)\, thus showing that the disorder is strongly
relevant.\n\nOur discussion will concern mainly the critical case\, i.e.\
, the case where the disorder is centered\, but we may also address the no
n-critical case.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/73/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Sara Murciano (LPTMS\, Université Paris-Saclay\, Orsay\, France)
DTSTART:20250618T100000Z
DTEND:20250618T110000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/74
DESCRIPTION:Title: Observable-projected ensemble\nby Sara Murciano (LPTMS\, U
niversité Paris-Saclay\, Orsay\, France) as part of Seed Seminar of Mathe
matics and Physics\n\nLecture held in IHES\, Amphithéâtre Léon Motchane
.\n\nAbstract\nLocal measurements in many‐body quantum systems can produ
ce surprising phenomena—from preparing long‐range entangled states to
driving measurement‐induced phase transitions and modifying critical beh
avior. In this talk\, I will introduce a new “observable‐projected”
protocol: rather than performing complete projective measurements on the c
omplement of a subsystem\, we measure a single\, local Hermitian operator
on part of that complement. The result is a mixed‐state ensemble on the
subsystem that remains analytically tractable within a conformal field the
ory framework. I will then show how this ensemble’s entanglement structu
re can be computed\, and present a detailed case study of the free compact
boson.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/74/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Alessio Lerose (Department of Physics and Astronomy\, KU Leuven)
DTSTART:20250611T083000Z
DTEND:20250611T093000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/76
DESCRIPTION:Title: Thermalization and ergodicity breaking in quantum many-body sy
stems\nby Alessio Lerose (Department of Physics and Astronomy\, KU Leu
ven) as part of Seed Seminar of Mathematics and Physics\n\nLecture held in
Online and streamed at Amphithéâtre Léon Motchane.\n\nAbstract\nNon-eq
uilibrium dynamics of isolated quantum many-body systems plays an importan
t role in contemporary theoretical physics research\, from foundational qu
estions on quantum statistical mechanics to the development of quantum tec
hnologies.\n\nI will provide a guided tour of a selection of results on th
ermalization and ergodicity breaking in quantum many-body dynamics\, with
an eye on mathematically rigorous studies\, including (many) conjectures a
nd (few) proven statements.\n\nOnline talk. It will be streamed at IHES. T
o get the link\, please register at https://seedseminar.apps.math.cnrs.fr/
\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/76/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Philine van Vliet (LPTENS\, École Normale Supérieure)
DTSTART:20250709T073000Z
DTEND:20250709T083000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/77
DESCRIPTION:Title: 1d Long-range Ising model near the short-range crossover\n
by Philine van Vliet (LPTENS\, École Normale Supérieure) as part of Seed
Seminar of Mathematics and Physics\n\nLecture held in IHES\, Amphithéât
re Léon Motchane.\n\nAbstract\nOne of the features of the critical behavi
or of the long-range Ising model (LRI) with interactions decaying as $1/r^
{s+d}$ is that it has a line of interacting fixed points\, and hence corre
sponds to a family of interacting $d$-dimensional CFT\, for $d/2 < s < s_{
*}$. Both ends of this range of $s$ admit a weakly-coupled description. Fo
r small $s$\, the theory is described as a generalized free field with a $
\\phi^{4}$ interaction. For large $s$\, the theory can be described by the
$d$-dimensional short-range Ising model (SRI) coupled to a generalized fr
ee field. While these descriptions have been used to study the LRI in dime
nsions $d>1$\, in $d=1$ it leads to a fascinating puzzle. The $1d$ LRI sti
ll has a line of interacting fixed points for $1/2Lipschitz continuity of diffusion transport maps from a contro
l perspective\nby Katharina Eichinger (LMO\, Paris-Saclay and Inria Pa
rMA) as part of Seed Seminar of Mathematics and Physics\n\nLecture held in
IHES\, Amphithéâtre Léon Motchane.\n\nAbstract\nLipschitz transport ma
ps between two measures are useful tools for transferring analytical prope
rties\, such as functional inequalities. The most well-known result in thi
s field is Caffarelli’s contraction theorem\, which shows that the optim
al transport map from a Gaussian to a uniformly log-concave measure is glo
bally Lipschitz. Note that the transfer of analytical properties does not
depend on the optimality of the transport map. This is why several works h
ave established Lipschitz bounds for other transport maps\, such as those
derived from diffusion processes\, as introduced by Kim and Milman. Here\,
we use the control interpretation of the transport vector field inducing
the transport map and a coupling strategy to obtain Lipschitz bounds for t
his map between asymptotically log-concave measures and their Lipschitz pe
rturbations. This talk is based on a joint work with Giovanni Conforti.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/78/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Fanny Eustachon (CPhT\, École polytechnique)
DTSTART:20250709T100000Z
DTEND:20250709T110000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/79
DESCRIPTION:Title: The effective field theory realizations of the perfect fluid\nby Fanny Eustachon (CPhT\, École polytechnique) as part of Seed Semin
ar of Mathematics and Physics\n\nLecture held in IHES\, Amphithéâtre Lé
on Motchane.\n\nAbstract\nHydrodynamics is one of the oldest example of fi
eld theories\, describing the long-range behaviour of many-body systems an
d its study remained mostly classical. Nevertheless\, near zero temperatur
e\, quantum fluctuations grow in importance raising the natural question:
is there a consistent quantum picture of a perfect fluid at zero temperatu
re?\n\nIn this talk\, I will review the subtly inequivalent Lagrangians re
alizations of the perfect fluid through the lens of modern effective field
theory (EFT). I will then discuss its particularity\, naming the presence
of an infinitely dimensional symmetry. As we will see\, its main implicat
ion is the existence of transverse modes with vanishing dispersion relatio
n at the classical level\, and an infinitely degenerate spectrum and UV-IR
mixing at the quantum level.\n\nThis is based on a work with G. Cuomo\, E
. Firat\, B. Henning and R. Rattazzi https://arxiv.org/abs/2412.10344.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/79/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Andrea Sportiello (CNRS and LIPN\, Université Sorbonne Paris Nord
)
DTSTART:20251029T123000Z
DTEND:20251029T133000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/80
DESCRIPTION:Title: Grassmann Calculus for the combinatorics of Spanning Trees and
Forests\nby Andrea Sportiello (CNRS and LIPN\, Université Sorbonne P
aris Nord) as part of Seed Seminar of Mathematics and Physics\n\n\nAbstrac
t\nIn this talk we will make a survey of how techniques of ``Grassmann\nCa
lculus''\, that is\, integration of expressions involving\nanticommuting v
ariables\, provide fermionic analogues of Gaussian\nintegration\, Wick's T
heorem and perturbative field theory. These\ntechniques are specially frui
tful for describing certain combinatorial\nmodels in Statistical Mechanics
\, namely $n=2$ Loop Models\, Spanning\nTrees\, and Spanning Forests.\n\nI
f the time permits\, we will also show how the model of Spanning\nForests\
, in its Grassmann-variable formulation\, has a hidden ${\\mathrm{OSp}}(1\
\vert 2)$ supersymmetry\, that\, by the Parisi--Sourlas\nmechanism\, impli
es that it must be in the same universality class of\nthe $O(n)$ loop mode
l in the analytic continuation $n\\to -1$.\n\nMostly based on (old) works
in collaboration with S. Caracciolo and\nA.D. Sokal.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/80/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Julien Weibel (INRIA & ENS Paris)
DTSTART:20251029T153000Z
DTEND:20251029T163000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/81
DESCRIPTION:Title: Probability-graphons: limits for sequences of large dense weig
hted graphs\nby Julien Weibel (INRIA & ENS Paris) as part of Seed Semi
nar of Mathematics and Physics\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/81/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Camille Cazaux (LPSM)
DTSTART:20251126T104500Z
DTEND:20251126T114500Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/82
DESCRIPTION:Title: Limiting Degree Distribution for a Sublinear Preferential Atta
chment Model with Communities\nby Camille Cazaux (LPSM) as part of See
d Seminar of Mathematics and Physics\n\n\nAbstract\nFor many real-world ne
tworks\, such as the World Wide Web\, the degree distribution follows a po
wer law. It is therefore useful to have simple random graph models whose l
imiting degree distribution exhibits this same feature. With this motivati
on\, physicists Albert-László Barabási and Réka Albert introduced the
preferential attachment model that now bears their name. A further advanta
ge of this model is that it incorporates temporal dynamics: starting from
an initial graph $\\mathcal{G}_0$\, the graph at time $n+1$ is obtained fr
om the graph at time $n$\, denoted $\\mathcal{G}_n$\, by adding a new vert
ex $v_{n+1}$. This vertex then attaches to one or several vertices of $\\m
athcal{G}_n$ according to a preferential attachment rule\, meaning that th
e probability of connecting to a given vertex of $\\mathcal{G}_n$ is propo
rtional to its degree.\n\nWe present an extension of this model in which e
ach vertex of the graph is assigned a community (or type)\, and in which t
he preferential attachment is sublinear\; that is\, the probability of att
aching to a vertex $u$ is proportional to $\\deg(u)^\\gamma$\, where $\\ga
mma$ is a parameter taking values in $(0\,1)$.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/82/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Jesper Jacobsen (LPTENS)
DTSTART:20251210T093000Z
DTEND:20251210T103000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/89
DESCRIPTION:Title: Three-point functions in critical loop models\nby Jesper J
acobsen (LPTENS) as part of Seed Seminar of Mathematics and Physics\n\n\nA
bstract\nIn two-dimensional models of critical non-intersecting loops\, we
conjecture an exact formula for three-point functions of fields that inse
rt legs (open loop segments) and can have nonzero conformal spin. The conj
ecture extends a previous result for diagonal fields\, recently proved by
Ang-Cai-Sun-Wu\, who also proved our conjecture for three spinless two-leg
operators. We discuss in details the supporting evidence for our general
conjecture coming from transfer-matrix computations using the unoriented J
ones-Temperley-Lieb algebra.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/89/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Sonia Boulal (Institut Denis Poisson Université d’Orléans)
DTSTART:20251029T140000Z
DTEND:20251029T150000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/90
DESCRIPTION:Title: Conditioned Marked Galton-Watson trees\nby Sonia Boulal (I
nstitut Denis Poisson Université d’Orléans) as part of Seed Seminar of
Mathematics and Physics\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/90/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Giuseppe Scola (UNICAL (Università della Calabria))
DTSTART:20251126T093000Z
DTEND:20251126T103000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/91
DESCRIPTION:Title: Point of a ψ^4_d Fermionic Theory: Anomalous Exponent and Sca
ling Operators\nby Giuseppe Scola (UNICAL (Università della Calabria)
) as part of Seed Seminar of Mathematics and Physics\n\n\nAbstract\nWe con
sider the Renormalization Group (RG) fixed-point theory associated with a
fermionic $\\psi^4_d$ model in $d= 1\, 2\, 3$ with fractional kinetic term
\, whose scaling dimension is fixed so that the quartic interaction is wea
kly relevant in the RG sense. The model is defined in terms of a Grassmann
functional integral with interaction V*\, solving a fixed-point RG equati
on in the presence of external fields\, and a fixed ultraviolet cutoff. We
define and construct the field and density scale-invariant response funct
ions\, and prove that the critical exponent of the former is the naive one
\, while that of the latter is anomalous and analytic. We construct the co
rresponding (almost-)scaling operators\, whose two point correlations are
scale-invariant up to a remainder term\, which decays like a stretched exp
onential at distances larger than the inverse of the ultraviolet cutoff. O
ur proof is based on constructive RG methods and\, specifically\, on a con
vergent tree expansion for the generating function of correlations\, which
generalizes the approach developed by three of the authors in a previous
publication (Giuliani et al. in JHEP 01:026\, 2021. https://doi.org/10.100
7/JHEP01(2021)026). \nCMP 406.10 (2025): 257\, joint work with A. Giuliani
\, V. Mastropietro and S. Rychkov.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/91/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Vincent Viau (LAGA\, USPN)
DTSTART:20251112T130000Z
DTEND:20251112T140000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/92
DESCRIPTION:Title: Supercritical frozen Erdős-Rényi and uniform random forests<
/a>\nby Vincent Viau (LAGA\, USPN) as part of Seed Seminar of Mathematics
and Physics\n\n\nAbstract\nThe frozen Erdős-Rényi random graph is a vari
ant of the standard dynamical Erdős-Rényi random graph that prevents the
creation of the giant component by freezing the evolution of connected co
mponents with a unique cycle. The formation of multicyclic components is f
orbidden\, and the growth of components with a unique cycle is slowed down
\, depending on a parameter $p\\in[0\, 1]$ that quantifies the slowdown. I
n this talk\, we will study the fluid limit of the main statistics of this
process\, that is their functional convergence as the number of vertices
of the graph becomes large and after a proper rescaling\, to the solution
of a system of differential equations. The proof is based on the free fore
st property of the frozen model: the forest part of the graph is a uniform
random forest. In order to prove the fluid limit results\, we will explai
n how to study and count forests using conditioned random walks.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/92/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Vladimir Narovlansky (School of Natural Sciences\, IAS)
DTSTART:20251112T141500Z
DTEND:20251112T151500Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/93
DESCRIPTION:Title: Dualities between fermionic theories and the Potts model\n
by Vladimir Narovlansky (School of Natural Sciences\, IAS) as part of Seed
Seminar of Mathematics and Physics\n\n\nAbstract\nWe show that a large cl
ass of fermionic theories are dual to a $q\\to 0$ limit of the Potts model
in the presence of a magnetic field. These can be described using a stati
stical model of random forests on a graph\, generalizing the (unrooted) ra
ndom forest description of the Potts model with only nearest neighbor inte
ractions. We then apply this to find a statistical description of a recent
ly introduced family of $OSp(1|2M)$ invariant field theories that provide
a UV completion to sigma models with the same symmetry.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/93/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Lucas Rey (DMA\, ENS)
DTSTART:20251210T104500Z
DTEND:20251210T114500Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/94
DESCRIPTION:Title: The near-critical dimer model and the sine-Gordon field\nb
y Lucas Rey (DMA\, ENS) as part of Seed Seminar of Mathematics and Physics
\n\n\nAbstract\nThe study of critical models is of the more active areas o
f statistical mechanics. Regarding the dimer model\, the convergence of th
e critical model towards the Gaussian free field was obtained around 25 ye
ars ago by Kenyon. More recently\, perturbations of the critical model kno
wn as near-critical models have been considered\, and some convergence res
ults have been obtained\, in particular for the Ising model. Convergence r
esults have also been obtained for the near-critical dimer model\, which d
id not allow to identify the limiting field\, even though it was conjectur
ed to be the sine-Gordon field. I will present a derivation of the limit u
sing discrete massive holomorphy techniques\, which expresses the limiting
field as the solution of a certain Dirichlet problem associated with a ma
ssive Dirac operator. I will finally explain how to relate this field to t
he sine-Gordon field. This is based on an ongoing work with Nathanaël Ber
estycki and Scott Mason.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/94/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Julio Parra-Martinez (IHES)
DTSTART:20250128T123000Z
DTEND:20250128T133000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/95
DESCRIPTION:by Julio Parra-Martinez (IHES) as part of Seed Seminar of Math
ematics and Physics\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/95/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Eric Pichon-Pharabod (Max Planck Institute for Mathematics in the
Sciences\, Leipzig)
DTSTART:20250128T140000Z
DTEND:20250128T150000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/96
DESCRIPTION:by Eric Pichon-Pharabod (Max Planck Institute for Mathematics
in the Sciences\, Leipzig) as part of Seed Seminar of Mathematics and Phys
ics\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/96/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Roberta Angius (University of Hamburg)
DTSTART:20250128T153000Z
DTEND:20250128T163000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/97
DESCRIPTION:by Roberta Angius (University of Hamburg) as part of Seed Semi
nar of Mathematics and Physics\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/97/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Stefano De Angelis (IPhT)
DTSTART:20250204T093000Z
DTEND:20250204T103000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/98
DESCRIPTION:by Stefano De Angelis (IPhT) as part of Seed Seminar of Mathem
atics and Physics\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/98/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Sara Maggio (Department of Physics and Astronomy\, University of B
onn)
DTSTART:20250204T104500Z
DTEND:20250204T114500Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/99
DESCRIPTION:by Sara Maggio (Department of Physics and Astronomy\, Universi
ty of Bonn) as part of Seed Seminar of Mathematics and Physics\n\nAbstract
: TBA\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/99/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Carlo Heissenberg (IPhT)
DTSTART:20250218T093000Z
DTEND:20250218T103000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/100
DESCRIPTION:by Carlo Heissenberg (IPhT) as part of Seed Seminar of Mathema
tics and Physics\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/100/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Erik Panzer (Mathematical Institute\, University of Oxford)
DTSTART:20250218T104500Z
DTEND:20250218T114500Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/101
DESCRIPTION:by Erik Panzer (Mathematical Institute\, University of Oxford)
as part of Seed Seminar of Mathematics and Physics\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/101/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Mehregan Doroudiani (School of Physics and Astronomy\, University
of Southampton)
DTSTART:20250304T093000Z
DTEND:20250304T103000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/102
DESCRIPTION:by Mehregan Doroudiani (School of Physics and Astronomy\, Univ
ersity of Southampton) as part of Seed Seminar of Mathematics and Physics\
n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/102/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Thomas Pochart (CPhT\, École polytechnique)
DTSTART:20250304T104500Z
DTEND:20250304T114500Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/103
DESCRIPTION:by Thomas Pochart (CPhT\, École polytechnique) as part of See
d Seminar of Mathematics and Physics\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/103/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Julio Parra-Martinez (IHES)
DTSTART:20250128T123000Z
DTEND:20250128T133000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/104
DESCRIPTION:by Julio Parra-Martinez (IHES) as part of Seed Seminar of Math
ematics and Physics\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/104/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Eric Pichon-Pharabod (Max Planck Institute for Mathematics in the
Sciences\, Leipzig)
DTSTART:20260128T140000Z
DTEND:20260128T150000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/105
DESCRIPTION:Title: Numerical computations of periods and monodromy representatio
ns\nby Eric Pichon-Pharabod (Max Planck Institute for Mathematics in t
he Sciences\, Leipzig) as part of Seed Seminar of Mathematics and Physics\
n\n\nAbstract\nThe period matrix of a smooth complex projective variety en
codes the isomorphism between its singular homology and its algebraic De R
ham cohomology. Numerical approximations with sufficient precision of the
entries of the period matrix allow to recover some algebraic invariants of
the variety. Such approximations can be obtained from an effective descri
ption of the homology of the variety\, which itself can be obtained from t
he monodromy representation associated to a generic fibration. I will desc
ribe these methods to several hundred digits\, and showcase implementation
s and applications\, in particular to computation of the Picard rank of ce
rtain K3 surfaces.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/105/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Roberta Angius (University of Hamburg)
DTSTART:20260128T153000Z
DTEND:20260128T163000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/106
DESCRIPTION:Title: Thimble decomposition and Wall Crossing Structure for Physica
l Integrals\nby Roberta Angius (University of Hamburg) as part of Seed
Seminar of Mathematics and Physics\n\n\nAbstract\nA growing body of evide
nce suggests that the complexity of physical integrals is most naturally u
nderstood through geometry. Recent mathematical developments by Kontsevich
and Soibelman [arXiv:2402.07343] have illuminated the role of exponential
integrals as periods of twisted de Rham cocycles over Betti cycles\, offe
ring a structured approach to address this problem in a wide range of sett
ings. In this talk\, I will first introduce the key tools underlying this
structure and then apply them to show how families of physically relevant
integrals\, ranging from holomorphic exponentials to logarithmic multivalu
ed functions\, can be reformulated within this language. For holomorphic e
xponents\, I will present an explicit decomposition of a family of integra
ls into thimbles expansion together with a detailed analysis of the wall-c
rossing structure behind the analytic continuation of its relevant paramet
er. Finally\, I will discuss the generalization to multivalued functions\,
which provides the appropriate framework for describing Feynman integrals
in special representations.\nIn this context\, the thimble decomposition
is expected to match the decomposition into Master\nIntegrals\, while the
study of the wall-crossing structure yields a precise count of independent
Master Integrals (or periods)\, circumventing complications arising from
Stokes phenomena\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/106/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Stefano De Angelis (IPhT)
DTSTART:20260304T083000Z
DTEND:20260304T093000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/107
DESCRIPTION:by Stefano De Angelis (IPhT) as part of Seed Seminar of Mathem
atics and Physics\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/107/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Sara Maggio (University of Bonn)
DTSTART:20260204T103000Z
DTEND:20260204T113000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/108
DESCRIPTION:Title: From polylogs to Calabi–Yau: canonical differential equatio
ns and intersection theory\nby Sara Maggio (University of Bonn) as par
t of Seed Seminar of Mathematics and Physics\n\n\nAbstract\nFeynman integr
als whose associated geometries extend beyond the Riemann sphere\, such as
elliptic and Calabi–Yau geometries\, are becoming increasingly relevant
in modern precision calculations. They arise not only in collider cross-s
ection computations\, but also in gravitational-waves scattering.
A powerful approach to compute such integrals is based on systems
of differential equations\, in particular when these can be brought into
a canonical form\, in which their singularity structure is manifest. In th
is talk\, I will show that canonical Feynman integrals do enjoy similar pr
operties\, albeit different associated geometries\, and I will illustrate
how intersection theory can be used to further study and constraint the fu
nctions appearing in the amplitudes.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/108/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Carlo Heissenberg (IPhT)
DTSTART:20250218T093000Z
DTEND:20250218T103000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/109
DESCRIPTION:by Carlo Heissenberg (IPhT) as part of Seed Seminar of Mathema
tics and Physics\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/109/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Erik Panzer (University of Oxford)
DTSTART:20250218T104500Z
DTEND:20250218T114500Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/110
DESCRIPTION:by Erik Panzer (University of Oxford) as part of Seed Seminar
of Mathematics and Physics\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/110/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Mehregan Doroudiani (University of Southampton)
DTSTART:20260304T094500Z
DTEND:20260304T104500Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/111
DESCRIPTION:Title: Scattering amplitude of closed strings at genus one\nby M
ehregan Doroudiani (University of Southampton) as part of Seed Seminar of
Mathematics and Physics\n\n\nAbstract\nPerturbative calculations of string
amplitudes are twofold: an expansion in the string coupling (the genus ex
pansion of the worldsheet) and a low-energy expansion in the momenta. In t
his talk\, I will focus on the low-energy expansion of closed string ampli
tudes at genus one\, specifically for four- and five-point massless states
of type IIB superstrings in flat spacetime. Evaluating these amplitudes i
nvolves integrating over the moduli space of punctured tori. I will demons
trate how the formalism of equivariant iterated Eisenstein integrals can b
e used to systematically calculate these integrals. Additionally\, I will
discuss the implications of these results for the S-duality of type IIB an
d conclude by exploring the underlying number-theoretic aspects of string
amplitudes.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/111/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Thomas Pochart (CPhT\, École polytechnique)
DTSTART:20260304T104500Z
DTEND:20260304T114500Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/112
DESCRIPTION:Title: Ruelle scattering theory and the single-particle problem in t
he Wightman framework\nby Thomas Pochart (CPhT\, École polytechnique)
as part of Seed Seminar of Mathematics and Physics\n\n\nAbstract\nIn this
presentation\, I will first review what purposes axiomatic quantum field
theory serves and what the Wightman framework is and achieves. With that b
eing \ndone\, I will address the question of the existence of the S-matrix
in this framework\, following a modern and dimension-independent approach
to the Haag--Ruelle scattering\; in doing so\, I will put a special empha
sis on the single-particle problem.\nWith all this discussion having taken
place in flat space\, I will conclude by presenting some ongoing work on
an AdS space version of these arguments.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/112/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Carlo Heissenberg (IPhT)
DTSTART:20250218T093000Z
DTEND:20250218T103000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/113
DESCRIPTION:by Carlo Heissenberg (IPhT) as part of Seed Seminar of Mathema
tics and Physics\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/113/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Erik Panzer (University of Oxford)
DTSTART:20250218T104500Z
DTEND:20250218T114500Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/114
DESCRIPTION:by Erik Panzer (University of Oxford) as part of Seed Seminar
of Mathematics and Physics\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/114/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Julio Para-Martinez (IHES)
DTSTART:20260128T123000Z
DTEND:20260128T133000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/115
DESCRIPTION:Title: Feynman Periods in Classical and Quantum Field Theory\nby
Julio Para-Martinez (IHES) as part of Seed Seminar of Mathematics and Phy
sics\n\n\nAbstract\nIn this talk I will review the appearance of periods a
s Feynman integral associated to classical and quantum scattering.\nUsing
some specific examples\, I will give a brief survey of the state of the ar
t of the subject and describe in which physical quantities they arise.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/115/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Carlo Heissemberg (Institut de Physique Théorique)
DTSTART:20260218T083000Z
DTEND:20260218T093000Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/116
DESCRIPTION:Title: Gravitational waveforms from differential equations\nby C
arlo Heissemberg (Institut de Physique Théorique) as part of Seed Seminar
of Mathematics and Physics\n\n\nAbstract\nThe direct detection of gravita
tional waves has put the relativistic two-body problem in the spotlight an
d stimulated progress in perturbative approaches that provide analytic ins
ight into its dynamics. Two strategies that have been witnessing interesti
ng developments to this end are the ones based on scattering amplitudes\,
which apply to binary scatterings at large impact parameter\, and on black
-hole perturbation theory\, which applies to extreme-mass-ratio binaries.
In this talk\, I will discuss how two very different kinds of differential
equations have been playing a key role in such recent developments\, in p
articular with the goal of characterizing the gravitational waves emitted
and (re)absorbed by these systems.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/116/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Erik Panzer (Oxford University)
DTSTART:20260218T104500Z
DTEND:20260218T114500Z
DTSTAMP:20260404T111138Z
UID:SeedSeminar/117
DESCRIPTION:Title: Tropical quantum field theory and asymptotics of perturbation
theory\nby Erik Panzer (Oxford University) as part of Seed Seminar of
Mathematics and Physics\n\n\nAbstract\nTo compute properties of phase tra
nsitions in condensed matter or the interactions of elementary particles\,
quantum field theory is typically solved perturbatively. This expansion p
roduces divergent series\, so the extraction of meaningful results (resumm
ation) is not straightforward. In fact\, very little is known about the ac
tual asymptotic behaviour of these series. In this talk\, I will introduce
a new limit of quantum field theory (the „tropical“ limit)\, which is
easily computable to very high orders in perturbation theory\, yet at the
same time captures the full complexity of subdivergences\, renormalizatio
n\, and scheme dependence. I will illustrate that the values of Feynman in
tegrals and their tropical limit are highly correlated. Based on data up t
o 400 loops\, we can precisely determine the asymptotic growth of the (tro
pical) beta function in different renormalization schemes. In particular\,
we find unexpectedly complicated instantons\, and we confirm the absence
of renormalons in the minimal subtraction scheme.\n
LOCATION:https://stable.researchseminars.org/talk/SeedSeminar/117/
END:VEVENT
END:VCALENDAR