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BEGIN:VEVENT
SUMMARY:Edgar Shaghoulian
DTSTART:20201002T120000Z
DTEND:20201002T130000Z
DTSTAMP:20260404T111001Z
UID:DurhamMathsHEP/1
DESCRIPTION:Title: Looking for islands\nby Edgar Shaghoulian as part of Dur
ham Maths HEP seminars\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/DurhamMathsHEP/1/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Domenico Orlando (INFN Turin)
DTSTART:20201016T120000Z
DTEND:20201016T130000Z
DTSTAMP:20260404T111001Z
UID:DurhamMathsHEP/2
DESCRIPTION:Title: Introduction to the large charge expansion\nby Domenico
Orlando (INFN Turin) as part of Durham Maths HEP seminars\n\nAbstract: TBA
\n
LOCATION:https://stable.researchseminars.org/talk/DurhamMathsHEP/2/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Tommaso Macrelli (University of Surrey)
DTSTART:20201023T120000Z
DTEND:20201023T130000Z
DTSTAMP:20260404T111001Z
UID:DurhamMathsHEP/3
DESCRIPTION:Title: BV formalism\, QFT and Gravity: a Homotopy perspective\n
by Tommaso Macrelli (University of Surrey) as part of Durham Maths HEP sem
inars\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/DurhamMathsHEP/3/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Akash Jain (University of Victoria)
DTSTART:20201030T130000Z
DTEND:20201030T140000Z
DTSTAMP:20260404T111001Z
UID:DurhamMathsHEP/4
DESCRIPTION:Title: Non-universality of hydrodynamics\nby Akash Jain (Univer
sity of Victoria) as part of Durham Maths HEP seminars\n\n\nAbstract\nThe
late-time long-distance behaviour of a many-body system is usually describ
ed by the framework of hydrodynamics or similar condensed matter models ba
sed on the (possibly spontaneously broken) symmetries that the system enjo
ys. These models are characterised by a set of transport coefficients\, su
ch as viscosities and conductivity\, that capture the transport properties
of conserved charges over macroscopic scales. In this talk\, we will inve
stigate a new kind of transport coefficients that are not present in the u
sual formulation of hydrodynamics\, but nonetheless affect the late time d
ynamics of conserved charges. Physically\, these new coefficients arise du
e to the interaction of the hydrodynamic degrees of freedom with the backg
round bath of thermal noise present out of equilibrium. For the purposes o
f this investigation\, I will spend some time to review the newly develope
d Schwinger-Keldysh effective action formulation of non-equilibrium field
theories\, which allows one to systematically keep track of thermal noise
and their correlations. The talk will be based on the recent preprint http
s://arxiv.org/abs/2009.01356.\n
LOCATION:https://stable.researchseminars.org/talk/DurhamMathsHEP/4/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Andrea Ferrari (Durham University)
DTSTART:20201106T130000Z
DTEND:20201106T140000Z
DTSTAMP:20260404T111001Z
UID:DurhamMathsHEP/5
DESCRIPTION:Title: A pedestrian introduction to the geometry of 3d twisted indi
ces\nby Andrea Ferrari (Durham University) as part of Durham Maths HEP
seminars\n\n\nAbstract\n3d $N=2$ gauge theories enjoy a twist that allows
to study their partition functions on a circle times a closed Riemann sur
face. These partition functions\, known as twisted indices\, were computed
some time ago using supersymmetric localisation on the Coulomb branch. Mo
re recently\, we interpreted the indices from the point of view of a super
symmetric quantum mechanics\, unveiling interesting connections to geometr
y. Starting from simple quantum mechanical geometric models\, in this talk
we want to introduce this point of view and explain how the indices encod
e interesting geometric phenomena such as wall-crossing and\, in the case
of $N=4$ gauge theories\, symplectic duality of quasi-maps. The talk is ba
sed on arxiv:1802.10120\, arxiv:1812.05567\, arxiv:1912.9591\, arxiv:2007.
11603.\n
LOCATION:https://stable.researchseminars.org/talk/DurhamMathsHEP/5/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Federico Carta (Durham University)
DTSTART:20201113T131500Z
DTEND:20201113T141500Z
DTSTAMP:20260404T111001Z
UID:DurhamMathsHEP/6
DESCRIPTION:Title: Supersymmetry Enhancement\nby Federico Carta (Durham Uni
versity) as part of Durham Maths HEP seminars\n\n\nAbstract\nIn the last c
ouple of years it was discovered that some 4d N=1 quantum field theories f
low in the IR to 4d N=2 superconformal field theories (often of generalize
d Argyres-Douglas type)\, therefore showing a phenomenon of Supersymmetry
Enhancement at the IR fixed point. Such flows are extremely useful in orde
r to learn features of the IR non-lagrangian theory\, by using the UV form
ulation to compute RG flow protected quantities. However\, up to date it i
s not completely clear why such flows exist\, and how the SUSY Enhancement
mechanism works in detail. Limiting ourself to one class of such flows\,
usually referred as Maruyoshi-Song flows\, we show how it is possible to u
nderstand the enhancement phenomenon in a geometric way\, by realizing thi
s setup in F-Theory. We also discuss how to understand the enhancement as
an hyperkahler structure restoration on the moduli space of solutions of t
he (generalized) Hitchin system associated to such theories. Finally\, we
discuss a very large systematic scan that we performed in order to find mo
re example of such flows. Having found none\, we conjecture that this part
icular method is exhausted: all the N=1 lagrangian theories flowing to Arg
yres-Douglas theory by Maruyoshi-Song RG-flows have been already discovere
d\, and there exist no more.\n
LOCATION:https://stable.researchseminars.org/talk/DurhamMathsHEP/6/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Yuya Tanizaki (Kyoto University)
DTSTART:20201120T130000Z
DTEND:20201120T140000Z
DTSTAMP:20260404T111001Z
UID:DurhamMathsHEP/7
DESCRIPTION:Title: Topological aspects of oblique confinement in the Cardy-Rabi
novici model\nby Yuya Tanizaki (Kyoto University) as part of Durham Ma
ths HEP seminars\n\n\nAbstract\nConfinement is one of the most important b
ut basic features of non-Abelian gauge theories\, and an intuitive and int
eresting scenario of its dynamics is condensation of magnetic monopoles. W
hen we add the topological theta term to it\, more exotic condensations ma
y appear\, which are called oblique confinement phases. In a 4d lattice mo
del proposed by Cardy and Rabinovici\, such interesting phases can be expl
icitly realized. In this talk\, I will uncover its topological nature base
d on the recent applications of 't Hooft anomaly matching. Moreover\, it h
as been known that the local dynamics of Cardy-Rabinovici model shows the
SL(2\,Z) self-duality\, but it turns out that the self-duality does not ex
tend to the global aspect of the original theory. We cooked up a SL(2\,Z)
self-dual theory by gauging a part of the 1-form symmetry of the Cardy-Rab
inovici model\, and the self-duality has a mixed gravitational anomaly. Th
ese data give useful constraints to discuss the phase diagram.\n
LOCATION:https://stable.researchseminars.org/talk/DurhamMathsHEP/7/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Sebastian Mizera (IAS)
DTSTART:20201127T130000Z
DTEND:20201127T140000Z
DTSTAMP:20260404T111001Z
UID:DurhamMathsHEP/8
DESCRIPTION:Title: Feynman Integrals and Intersection Theory\nby Sebastian
Mizera (IAS) as part of Durham Maths HEP seminars\n\n\nAbstract\nSingulari
ty structure of scattering amplitudes is as intricate as it is inscrutable
. Work in this area over the recent years has been hinting at an existence
of a “scalar product” between Feynman integrals\, which would tell us
how to characterize their analytic behavior. In this talk I will explain
how to formulate this notion using the tools of intersection theory as wel
l as review its theoretical and practical applications.\n
LOCATION:https://stable.researchseminars.org/talk/DurhamMathsHEP/8/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Pietro Benetti Genolini (Cambridge University)
DTSTART:20201204T130000Z
DTEND:20201204T140000Z
DTSTAMP:20260404T111001Z
UID:DurhamMathsHEP/9
DESCRIPTION:Title: Instantons\, symmetries and anomalies in five dimensions
\nby Pietro Benetti Genolini (Cambridge University) as part of Durham Math
s HEP seminars\n\n\nAbstract\nFive-dimensional non-abelian gauge theories
have a U(1) global symmetry associated with instantonic particles. I will
describe a mixed ’t Hooft anomaly between this and other global symmetri
es of the theory\, namely the one-form center symmetry or ordinary flavor
symmetry for theories with fundamental matter. I will explore some general
dynamical properties of the candidate phases implied by the anomaly\, and
apply our results to supersymmetric gauge theories in five dimensions\, a
nalysing the symmetry enhancement patterns occurring at their conjectured
RG fixed points.\n
LOCATION:https://stable.researchseminars.org/talk/DurhamMathsHEP/9/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Thomas Mertens (Ghent University)
DTSTART:20201211T130000Z
DTEND:20201211T140000Z
DTSTAMP:20260404T111001Z
UID:DurhamMathsHEP/10
DESCRIPTION:Title: Liouville and JT quantum gravity - holography and matrix mo
dels\nby Thomas Mertens (Ghent University) as part of Durham Maths HEP
seminars\n\n\nAbstract\nIn this talk\, we will discuss recent progress in
understanding quantum gravity amplitudes (partition function and boundary
correlation functions) in Liouville gravity\, and how they limit to Jacki
w-Teitelboim (JT) correlators. We also discuss multiboundary and higher ge
nus amplitudes. We focus on two main results: the Liouville gravity answer
s look like q-deformations of the JT answers\, and Liouville gravity can b
e related to a 2d dilaton gravity with a sinh dilaton potential. We end wi
th discussions on supersymmetric extensions and work in progress. Based la
rgely on arXiv:2006.07072 and 2007.00998.\n
LOCATION:https://stable.researchseminars.org/talk/DurhamMathsHEP/10/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Guido Festuccia (Uppsala University)
DTSTART:20210122T130000Z
DTEND:20210122T140000Z
DTSTAMP:20260404T111001Z
UID:DurhamMathsHEP/11
DESCRIPTION:Title: Twisting with a flip\nby Guido Festuccia (Uppsala Unive
rsity) as part of Durham Maths HEP seminars\n\n\nAbstract\nI will consider
N=2 supersymmetric gauge theories on 4D compact manifolds with a Killing
vector field with isolated fixed points.\nStudying the realization of supe
rsymmetry in these theories leads to consider a generalization of the noti
on of self-duality on manifolds with a vector field. This allows to constr
uct a framework unifying equivariant Donaldson-Witten theory and Pestun's
theory on S4 and its generalizations. I will also discuss the action of S-
duality in these theories.\n
LOCATION:https://stable.researchseminars.org/talk/DurhamMathsHEP/11/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Fabian Ruehle (CERN)
DTSTART:20210129T130000Z
DTEND:20210129T140000Z
DTSTAMP:20260404T111001Z
UID:DurhamMathsHEP/12
DESCRIPTION:Title: Moduli-dependent Calabi-Yau and SU(3)-structure metrics fro
m Machine Learning\nby Fabian Ruehle (CERN) as part of Durham Maths HE
P seminars\n\n\nAbstract\nCalabi-Yau manifolds play a crucial role in stri
ng compactifications. Yau's theorem guarantees the existence of a metric t
hat satisfies the string's equation of motion. However\, Yau's proof is no
n-constructive\, and no analytic expressions for metrics on Calabi-Yau thr
eefolds are known. We use machine learning\, more precisely neural network
s\, to learn Calabi-Yau metrics and their complex structure moduli depende
nce.\nI will start with an introduction to Calabi-Yau manifolds and their
moduli. After that\, I will give a brief introduction to neural networks.
Using an example\, I will then illustrate how we train neural networks to
find Calabi-Yau metrics by solving the underlying partial differential equ
ations. The approach generalizes to more general manifolds and can hence a
lso be used for manifolds with reduced structure\, such as SU(3) structure
or G2 manifolds\, which feature in string compactifications with flux and
in the M-theory formulation of string theory\, respectively. I will illus
trate this generalization for a particular SU(3) structure metric and comp
are the machine learning result to the known\, analytic expression.\n
LOCATION:https://stable.researchseminars.org/talk/DurhamMathsHEP/12/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Agnese Bissi (Uppsala University)
DTSTART:20210212T130000Z
DTEND:20210212T140000Z
DTSTAMP:20260404T111001Z
UID:DurhamMathsHEP/13
DESCRIPTION:Title: Towards all loop supergravity amplitudes\nby Agnese Bis
si (Uppsala University) as part of Durham Maths HEP seminars\n\n\nAbstract
\nIn this talk I will discuss how to extract the most trascendental piece
of the four graviton amplitude in type IIB supergravity on AdS_5×S^5 at a
ny loop order\, from the dual four point function in N=4 Super Yang Mills.
I will describe how to construct this part of the correlator/amplitude an
d its significance. I will conclude with some open problems and future dir
ections.\n
LOCATION:https://stable.researchseminars.org/talk/DurhamMathsHEP/13/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Joe Davighi (Cambridge University)
DTSTART:20210205T130000Z
DTEND:20210205T140000Z
DTSTAMP:20260404T111001Z
UID:DurhamMathsHEP/14
DESCRIPTION:Title: Anomaly interplay in even dimensions\nby Joe Davighi (C
ambridge University) as part of Durham Maths HEP seminars\n\n\nAbstract\nI
n any dimension\, a global anomaly in a symmetry G is detected by evaluati
ng the eta-invariant on a manifold with G-bundle in one higher dimension.
This manifold must be in a non-trivial bordism class (for there to be a gl
obal anomaly)\, making the evaluation of eta difficult in general. We disc
uss a strategy for evaluating many global anomalies in even dimensions\, w
hereby G is embedded in some larger group K for which the bordism group va
nishes. This allows one to extend the manifold with K-bundle as the bounda
ry of a manifold in one dimension higher still\, and thence to evaluate et
a from a local anomaly polynomial using the APS index theorem. We discuss
physics examples of this anomaly interplay in 2\, 4\, and 6 dimensions. In
4d\, we compute the global SU(2) anomaly from a local anomaly in U(2).\n
LOCATION:https://stable.researchseminars.org/talk/DurhamMathsHEP/14/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Diego Hofman (University of Amsterdam)
DTSTART:20210219T130000Z
DTEND:20210219T140000Z
DTSTAMP:20260404T111001Z
UID:DurhamMathsHEP/15
DESCRIPTION:Title: On the Stress Tensor Light-ray Operator Algebra\nby Die
go Hofman (University of Amsterdam) as part of Durham Maths HEP seminars\n
\n\nAbstract\nI will discuss correlation functions involving generalized A
NEC operators in four dimensions. In particular\, I’ll present computati
ons of two\, three\, and four-point functions involving external scalar st
ates in both free and holographic Conformal Field Theories. From this info
rmation\, I will comment on the algebra of these light-ray operators. Curi
ously\, a global subalgebra exists which annihilates the conformally invar
iant vacuum and is acted upon by the collinear conformal group that preser
ves the light-ray. Outside this set I’ll comment on the appearance of an
infinite central term\, in agreement with previous suggestions in the lit
erature. In free theories\, even some of the operators inside the global s
ubalgebra fail to commute when placed at spacelike separation on the same
null-plane. This lack of commutativity is not integrable\, presenting an o
bstruction to the construction of a well defined light-ray algebra at coin
cident coordinates. For holographic CFTs the behavior worsens and all gene
ralized operators (except for the ANEC) fail to commute at spacelike separ
ation. I will then discuss this same result from the bulk of AdS where new
exact shockwave solutions dual to the insertions of these (exponentiated)
operators can be used to perform the computation.\n
LOCATION:https://stable.researchseminars.org/talk/DurhamMathsHEP/15/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Elli Pomoni (DESY)
DTSTART:20210226T130000Z
DTEND:20210226T140000Z
DTSTAMP:20260404T111001Z
UID:DurhamMathsHEP/16
DESCRIPTION:Title: Type-B Anomalies on the Higgs Branch\nby Elli Pomoni (D
ESY) as part of Durham Maths HEP seminars\n\n\nAbstract\nIn this talk we w
ill study type-B conformal anomalies associated with 1/2-BPS Coulomb-branc
h operators in 4D N=2 SCFTs. We will derive the conditions under which the
se anomalies can match across the conformal phase and the Higgs phase\, an
d explicitly see them at work in concrete examples of both matching and no
n-matching. On the one hand matching leads to a new class of data on the H
iggs branch of 4D N=2 SCFTs that are exactly computable. On the other\, no
n-matching imposes novel restrictions on the holonomy of the conformal man
ifold.\n
LOCATION:https://stable.researchseminars.org/talk/DurhamMathsHEP/16/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Radu Tatar (Liverpool University)
DTSTART:20210305T130000Z
DTEND:20210305T140000Z
DTSTAMP:20260404T111001Z
UID:DurhamMathsHEP/17
DESCRIPTION:Title: de Sitter in the String Landscape\nby Radu Tatar (Live
rpool University) as part of Durham Maths HEP seminars\n\n\nAbstract\nI ar
gue that four-dimensional effective field theory descriptions with de Sitt
er isometries could be allowed in the presence of time-dependent internal
degrees of freedom in type IIB string landscape. Moduli stabilization and
time-independent Newton constants are possible in such backgrounds. Howeve
r once the time-dependences are switched off\, there appear no possibiliti
es of effective field theory descriptions.\n
LOCATION:https://stable.researchseminars.org/talk/DurhamMathsHEP/17/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Jacob McNamara (Harvard University)
DTSTART:20210312T130000Z
DTEND:20210312T140000Z
DTSTAMP:20260404T111001Z
UID:DurhamMathsHEP/18
DESCRIPTION:Title: Gravitational Solitons and Abelianization\nby Jacob McN
amara (Harvard University) as part of Durham Maths HEP seminars\n\n\nAbstr
act\nGravitational solitons are localized fluctuations of the topology of
spacetime\, and behave as dynamical particles or branes in theories of qua
ntum gravity. We study the possible charges of gravitational solitons unde
r dynamical gauge fields\, with an eye towards the completeness hypothesis
: that in a UV complete theory of quantum gravity\, there must exist state
s of every possible gauge charge. Remarkably\, we find that gravitational
solitons carry charges beyond those present in the pure gauge theory. We i
nterpret the role played by gravitational solitons as one of "abelianizati
on\," namely to remove any non-abelian complications from the completeness
hypothesis.\n
LOCATION:https://stable.researchseminars.org/talk/DurhamMathsHEP/18/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Evgeny Skvortsov (UMONS and Lebedev Institute)
DTSTART:20210423T120000Z
DTEND:20210423T130000Z
DTSTAMP:20260404T111001Z
UID:DurhamMathsHEP/19
DESCRIPTION:Title: Quantum Higher Spin Gravity and three-dimensional bosonizat
ion duality\nby Evgeny Skvortsov (UMONS and Lebedev Institute) as part
of Durham Maths HEP seminars\n\n\nAbstract\nHigher Spin Gravities are sup
posed to be minimalistic extensions of gravity that embed it into a quantu
m consistent theory. However\, such minimality turns out to be in tension
with the field theory approach\, as well as with the numerous no-go theore
ms. We report on the recent progress in constructing Higher Spin Gravities
and testing quantum effects therein. AdS/CFT relates Higher Spin Gravitie
s to a variety of interesting three-dimensional CFT's\, e.g. to the Ising
model. These CFT's were conjectured to exhibit a number of remarkable dual
ities\, in particular\, the three-dimensional bosonization duality. We sho
w how Higher Spin Gravity can be useful to prove the bosonization duality
at least in the large N limit and make new predictions for the correlation
functions.\n
LOCATION:https://stable.researchseminars.org/talk/DurhamMathsHEP/19/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Jaewon Song (KAIST)
DTSTART:20210319T130000Z
DTEND:20210319T140000Z
DTSTAMP:20260404T111001Z
UID:DurhamMathsHEP/20
DESCRIPTION:Title: Classification of large N superconformal gauge theories
\nby Jaewon Song (KAIST) as part of Durham Maths HEP seminars\n\n\nAbstrac
t\nWe classify the large N limits of four-dimensional supersymmetric gauge
theories with simple gauge groups that flow to superconformal fixed point
s. We restrict ourselves to the ones without a superpotential and with a f
ixed flavor symmetry. We find 35 classes in total\, with 8 having a dense
spectrum of chiral gauge-invariant operators. The central charges a and c
for the dense theories grow linearly in N in contrast to the N^2 growth fo
r the theories with a sparse spectrum. We find that there can be multiple
bands separated by a gap\, or a discrete spectrum above the band. For all
the theories with the dense spectrum\, the AdS version of the Weak Gravity
Conjecture holds for large enough N even though they do not have weakly-c
oupled gravity duals.\n
LOCATION:https://stable.researchseminars.org/talk/DurhamMathsHEP/20/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Marcus Berg (Karlstad University)
DTSTART:20210507T120000Z
DTEND:20210507T130000Z
DTSTAMP:20260404T111001Z
UID:DurhamMathsHEP/21
DESCRIPTION:Title: Plane gravitational waves and automorphic forms\nby Mar
cus Berg (Karlstad University) as part of Durham Maths HEP seminars\n\n\nA
bstract\nThe plane gravitational wave is a Penrose limit of AdS that is du
al to the gauge theory BMN limit. The string partition function in this ba
ckground provides a natural one-parameter deformation of Kronecker-Eisenst
ein series\, and more generally of Jacobi-Maass forms. This talk is based
on arXiv:1910.02745 and some work in progress.\n
LOCATION:https://stable.researchseminars.org/talk/DurhamMathsHEP/21/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Ivano Basile (Mons University)
DTSTART:20211015T120000Z
DTEND:20211015T130000Z
DTSTAMP:20260404T111001Z
UID:DurhamMathsHEP/22
DESCRIPTION:Title: Broken spacetime from broken supersymmetry\nby Ivano Ba
sile (Mons University) as part of Durham Maths HEP seminars\n\n\nAbstract\
nWe explore the dramatic consequences of string-scale supersymmetry breaki
ng. We focus on the USp(32) and U(32) orientifolds of the type IIB and typ
e 0B strings\, as well as the SO(16) x SO(16) projection of the exceptiona
l heterotic string\, which provide non-tachyonic settings with no moduli d
irectly in ten dimensions. While deceptively innocuous at the level of wor
ldsheet perturbation theory\, dynamical gravitational tadpoles backreact o
n spacetime in a dramatic fashion. We discuss how branes can tame this eff
ect to a certain extent\, finding that spacetime universally breaks down a
t a finite distance\, ending in a strongly coupled\, highly curved singula
rity. Remarkably\, the dynamics of branes in these settings remains consis
tent among different complementary regimes despite the absence of supersym
metric protection. We connect the resulting picture with a number of swamp
land criteria\, including the weak gravity\, de Sitter and distance conjec
tures\, which are realized via novel mechanisms.\n
LOCATION:https://stable.researchseminars.org/talk/DurhamMathsHEP/22/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Riccardo Borsato (Universidade de Santiago de Compostela)
DTSTART:20211022T120000Z
DTEND:20211022T130000Z
DTSTAMP:20260404T111001Z
UID:DurhamMathsHEP/23
DESCRIPTION:Title: A classification of solution-generating techniques in super
gravity and of canonical transformations of sigma-models\nby Riccardo
Borsato (Universidade de Santiago de Compostela) as part of Durham Maths H
EP seminars\n\n\nAbstract\nI will consider a two-fold problem: on the one
hand\, the classification of a family of solution-generating techniques in
supergravity and\, on the other hand\, the classification of a family of
canonical transformations of 2-dimensional sigma-models (giving rise to in
tegrable-preserving transformations). In fact\, under certain assumptions
that I will explain\, the two problems admit essentially the same algebrai
c formulation\, emerging from an underlying double Lie algebra. I will rev
iew the construction and the classification in terms of Lie algebra cohomo
logies. Based on 2102.04498 and 2109.06185.\n
LOCATION:https://stable.researchseminars.org/talk/DurhamMathsHEP/23/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Matthew Buican (Queen Mary University)
DTSTART:20211029T120000Z
DTEND:20211029T130000Z
DTSTAMP:20260404T111001Z
UID:DurhamMathsHEP/24
DESCRIPTION:Title: Some Galois Actions in Topological Quantum Field Theory
\nby Matthew Buican (Queen Mary University) as part of Durham Maths HEP se
minars\n\n\nAbstract\nGalois theory features prominently in many areas of
modern mathematics. Although somewhat less appreciated\, interesting (and
useful) Galois groups sometimes lurk beneath the surface in physics as wel
l. One particularly fruitful area for studying physical Galois actions is
in the context of TQFT and topological phases of matter. With this in mind
\, we will discuss some applications of Galois theory to the study of the
symmetries and structures present in 2+1 dimensional TQFT.\n
LOCATION:https://stable.researchseminars.org/talk/DurhamMathsHEP/24/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Philip Saad (IAS)
DTSTART:20211105T130000Z
DTEND:20211105T140000Z
DTSTAMP:20260404T111001Z
UID:DurhamMathsHEP/25
DESCRIPTION:Title: Comments on wormholes and factorization\nby Philip Saad
(IAS) as part of Durham Maths HEP seminars\n\n\nAbstract\nIn conventional
AdS/CFT partition functions of decoupled copies of the CFT factorize. In
bulk computations of such quantities contributions from spacetime wormhole
s which link separate asymptotic boundaries threaten to spoil this propert
y\, leading to a “factorization puzzle.” Certain simple models like JT
gravity and the SYK model have wormholes\, but bulk computations in them
correspond to averages over an ensemble of boundary systems. These average
s need not factorize. We can formulate a toy version of the factorization
puzzle in such models by focusing on a specific member of the ensemble whe
re partition functions will again factorize. In this talk we discuss bulk
computations of partition functions for (sometimes approximately) fixed me
mbers of the ensemble in three simple models: the topological model introd
uced by Marolf and Maxfield (the “MM model”)\, JT gravity\, and the SY
K model\, and give an effective description of the factorization mechanism
.\n
LOCATION:https://stable.researchseminars.org/talk/DurhamMathsHEP/25/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Chris Elliott (UMass Amherst)
DTSTART:20211112T130000Z
DTEND:20211112T140000Z
DTSTAMP:20260404T111001Z
UID:DurhamMathsHEP/26
DESCRIPTION:Title: Framing Anomalies for Topological AKSZ Theories\nby Chr
is Elliott (UMass Amherst) as part of Durham Maths HEP seminars\n\n\nAbstr
act\nI'll discuss an approach to the computation of framing anomalies usin
g the BV formalism. This method can be applied to a general class of topol
ogical field theories that encompasses many topological twists of supersym
metric gauge theories\, such as those 4d theories studied by Kapustin and
Witten in their work on the geometric Langlands correspondence. This talk
is based on joint work with Owen Gwilliam and Brian Williams.\n
LOCATION:https://stable.researchseminars.org/talk/DurhamMathsHEP/26/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Jackson Fliss (University of Amsterdam)
DTSTART:20211119T130000Z
DTEND:20211119T140000Z
DTSTAMP:20260404T111001Z
UID:DurhamMathsHEP/27
DESCRIPTION:Title: A carpenter’s guide to smeared inequalities\nby Jacks
on Fliss (University of Amsterdam) as part of Durham Maths HEP seminars\n\
n\nAbstract\nClassifying possible spacetime geometries is contingent on co
nstraining physically realizable stress-tensors\, objects famously describ
ed by Einstein as the “low grade wood” side of his field equation. The
situation is made even more precarious in quantum field theory where loca
l energy inequalities are violated. Working on this side of the field equa
tion\, I will review some recent work constraining null-energy smeared ove
r spacetime regions directly in quantum field theory. I will review and of
fer a field theoretic proof of the Smeared Null Energy Condition (a propos
ed generalization of the Null Energy Condition) and discuss recent work on
a Double Smeared Null Energy Condition lower-bounding the null-energy sme
ared over a particular spacetime region. Along the way\, I will detail gen
eral machinery for bounding below quantum operators that are classically p
ositive\, at least within a certain class of theories.\n
LOCATION:https://stable.researchseminars.org/talk/DurhamMathsHEP/27/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Lorenzo di Pietro (University of Trieste)
DTSTART:20211126T130000Z
DTEND:20211126T140000Z
DTSTAMP:20260404T111001Z
UID:DurhamMathsHEP/28
DESCRIPTION:Title: Conformal boundary conditions for free fields\nby Loren
zo di Pietro (University of Trieste) as part of Durham Maths HEP seminars\
n\n\nAbstract\nI will discuss the problem of classifying (interacting) con
formal boundary conditions for the simplest bulk conformal field theories:
free fields. I will mention concrete examples based on perturbation theor
y\, and then describe results using the numerical conformal bootstrap appr
oach\, specifically in the case of a scalar field in four and three bulk d
imensions.\n
LOCATION:https://stable.researchseminars.org/talk/DurhamMathsHEP/28/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Miranda Cheng (University of Amsterdam)
DTSTART:20211210T130000Z
DTEND:20211210T140000Z
DTSTAMP:20260404T111001Z
UID:DurhamMathsHEP/29
DESCRIPTION:Title: Machine learning and theoretical physics: some applications
\nby Miranda Cheng (University of Amsterdam) as part of Durham Maths H
EP seminars\n\n\nAbstract\nIn this talk I will briefly summarise some rece
nt work on the interactions between physics and machine learning. In a rec
ent paper (2110.02673) with de Haan\, Rainone\, and Bondesan\, we use a c
ontinuous flow model to help ameliorate the numerical difficulties in samp
ling in lattice field theories\, which for instance hampers high-precision
computations in LQCD. If time permits\, I will also talk about a second p
aper with V Anagiannis (2103.11785)\, in which we exploit the analogy betw
een quantum many-body systems and certain neural networks to analyse the l
earning process using quantum entanglement.\n
LOCATION:https://stable.researchseminars.org/talk/DurhamMathsHEP/29/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Costis Papageorgakis (Queen Mary University)
DTSTART:20220121T130000Z
DTEND:20220121T140000Z
DTSTAMP:20260404T111001Z
UID:DurhamMathsHEP/30
DESCRIPTION:Title: Towards Solving CFTs with Artificial Intelligence\nby C
ostis Papageorgakis (Queen Mary University) as part of Durham Maths HEP se
minars\n\n\nAbstract\nI will introduce a novel numerical approach for solv
ing the conformal-bootstrap equations with Reinforcement Learning. I will
apply this to the case of two-dimensional CFTs\, successfully identifying
well-known theories like the 2D Ising model and the 2D CFT of a compact sc
alar\, but the method can be used to study arbitrary (unitary or non-unita
ry) CFTs in any spacetime dimension.\n
LOCATION:https://stable.researchseminars.org/talk/DurhamMathsHEP/30/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Javier Magán (University of Pennsylvania)
DTSTART:20220128T130000Z
DTEND:20220128T140000Z
DTSTAMP:20260404T111001Z
UID:DurhamMathsHEP/31
DESCRIPTION:Title: Generalized Symmetries of the Graviton\nby Javier Magá
n (University of Pennsylvania) as part of Durham Maths HEP seminars\n\n\nA
bstract\nIn this talk we discuss the set of generalized symmetries associa
ted with the free graviton theory in four dimensions. These are generated
by ring-like operators. As for the Maxwell field\, we find a set of “ele
ctric” and a dual set of “magnetic” topological operators and comput
e their algebra. The associated electric and magnetic fields satisfy a set
of constraints equivalent to the ones of a stress tensor of a 3d CFT. Thi
s implies that the generalized symmetry is charged under space-time symmet
ries\, and it provides a bridge between linearized gravity and the tensor
gauge theories that have been introduced recently in the context of fracto
nic systems in condensed matter physics.\n
LOCATION:https://stable.researchseminars.org/talk/DurhamMathsHEP/31/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Alex Belin (CERN)
DTSTART:20220204T130000Z
DTEND:20220204T140000Z
DTSTAMP:20260404T111001Z
UID:DurhamMathsHEP/32
DESCRIPTION:Title: Quantum chaos\, OPE coefficients and wormholes\nby Alex
Belin (CERN) as part of Durham Maths HEP seminars\n\n\nAbstract\nIn this
talk\, I will discuss the statistical distribution of OPE coefficients in
chaotic conformal field theories. I will present the OPE Randomness Hypoth
esis (ORH)\, a generalization of ETH to CFTs which treats any OPE coeffici
ent involving a heavy operator as a pseudo-random variable with an approxi
mate Gaussian distribution. I will then present some evidence for this con
jecture\, based on the size of the non-Gaussianities and on insights from
random matrix theory. Turning to the bulk\, I will argue that semi-classic
al gravity geometrizes these statistical correlations by wormhole geometri
es. I will show that the non-Gaussianities of the OPE coefficients predict
a new connected wormhole geometry that dominates over the genus-2 wormhol
e.\n
LOCATION:https://stable.researchseminars.org/talk/DurhamMathsHEP/32/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dalimil Mazáč (IAS)
DTSTART:20220211T130000Z
DTEND:20220211T140000Z
DTSTAMP:20260404T111001Z
UID:DurhamMathsHEP/33
DESCRIPTION:Title: Automorphic Spectra and the Conformal Bootstrap\nby Dal
imil Mazáč (IAS) as part of Durham Maths HEP seminars\n\n\nAbstract\nI
will explain that the spectral geometry of hyperbolic manifolds provides
a remarkably faithful model of the modern conformal bootstrap. In particul
ar\, to each hyperbolic D-manifold\, one can associate a Hilbert space of
local operators\, which is a unitary representation of a conformal group.
The local operators live in an emergent (D-1)-dimensional spacetime. The s
caling dimensions of the operators are related to the eigenvalues of the L
aplacian on the manifold. The operators satisfy an operator product expans
ion. Finally\, one can define their correlation functions and derive boots
trap equations constraining the spectrum. As an application\, I will use c
onformal bootstrap techniques to derive upper bounds on the lowest positiv
e eigenvalue of the Laplacian on closed hyperbolic surfaces and 2-orbifold
s. In a number of notable cases\, the bounds are nearly saturated by known
surfaces and orbifolds. For instance\, the bound on all genus-2 surfaces
is λ1≤3.8388976481\, while the Bolza surface has λ1≈3.838887258. The
talk will be based on https://arxiv.org/abs/2111.12716\, which is joint w
ork with P. Kravchuk and S. Pal.\n
LOCATION:https://stable.researchseminars.org/talk/DurhamMathsHEP/33/
END:VEVENT
END:VCALENDAR