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BEGIN:VEVENT
SUMMARY:Nathan Seiberg (IAS)
DTSTART:20200427T210000Z
DTEND:20200427T220000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/1
DESCRIPTION:Title: Continuum Quantum Field Theories for Fractons\nby Nathan Se
iberg (IAS) as part of SITP seminar\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/1/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Po-shen Hsin (Caltech)
DTSTART:20200511T210000Z
DTEND:20200511T220000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/2
DESCRIPTION:Title: Berry phase in quantum field theory\nby Po-shen Hsin (Calte
ch) as part of SITP seminar\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/2/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Hong Liu (MIT)
DTSTART:20200504T210000Z
DTEND:20200504T220000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/3
DESCRIPTION:Title: Void formation in operator growth\, quantum chaos and black hol
e evaporation\nby Hong Liu (MIT) as part of SITP seminar\n\nAbstract:
TBA\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/3/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Tom Hartman (Cornell)
DTSTART:20200518T210000Z
DTEND:20200518T220000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/4
DESCRIPTION:Title: Sphere packing\, 3d gravity\, and the bootstrap\nby Tom Har
tman (Cornell) as part of SITP seminar\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/4/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Riccardo Rattazzi (EPFL)
DTSTART:20200601T210000Z
DTEND:20200601T220000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/5
DESCRIPTION:Title: Multilegs\, Superfluids and Semiclassics\nby Riccardo Ratta
zzi (EPFL) as part of SITP seminar\n\n\nAbstract\nEven in weakly coupled Q
FTs\, perturbation theory breaks down when one considers amplitudes with
a large number $n$ of legs. The series cleverly organizes as a double exp
ansion in $g^2$ and $g^2n$. I show how the series in $g^2n$ can be full
y captured by a semiclassical expansion around a non-trivial solution. Foc
ussing on $U(1)$ symmetric $|\\phi|^4$ theory in $4$ and $4-\\epsilon$ dim
ension I derive explict and consistent all order results for the anomalous
dimension of the complex operator $\\phi^n$. When restricting to the Wil
son-Fisher fixed point and working on the cylinder\, the dominant trajecto
ry is seen to correspond to a superfluid phase for the conserved U(1). Thi
s creates a remarkable correspondence between\, on one side\, the spectru
m of operators and fusion coeffcients and and on the other the spectrum of
hydrodynamics modes and their interactions. The results also nicely match
Monte Carlo simulations in 3D\, compatibly with the stunt of taking $\\ep
silon=1$.\n\n\n\nPlease subscribe through this link for notifications:\n\n
https://docs.google.com/forms/d/e/1FAIpQLSftoD33H-yK9G3ePko8LfNpsLE9gLg92T
JBXYzOja8LN3RZ4Q/viewform?vc=0&c=0&w=1&fbclid=IwAR1NIjCxv6kezbJdkms0x3oDmz
MhxbhORGkCx-OU3vsc6C9xlzGTfKBX7GM\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/5/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Kristan Jensen (SFSU)
DTSTART:20200608T210000Z
DTEND:20200608T220000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/6
DESCRIPTION:Title: Wormholes in AdS3 gravity and random matrix theory\nby Kris
tan Jensen (SFSU) as part of SITP seminar\n\nAbstract: TBA\n\nPlease subsc
ribe through this link for notifications:\n\nhttps://docs.google.com/forms
/d/e/1FAIpQLSftoD33H-yK9G3ePko8LfNpsLE9gLg92TJBXYzOja8LN3RZ4Q/viewform?vc=
0&c=0&w=1&fbclid=IwAR1NIjCxv6kezbJdkms0x3oDmzMhxbhORGkCx-OU3vsc6C9xlzGTfKB
X7GM\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/6/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Finn Larsen (UMich)
DTSTART:20200615T210000Z
DTEND:20200615T220000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/7
DESCRIPTION:Title: Microscopic Entropy of AdS Black Holes\nby Finn Larsen (UMi
ch) as part of SITP seminar\n\n\nAbstract\nTITLE\nMicroscopic Entropy of A
dS Black Holes\n\nABSTRACT\nThe interpretation of black hole entropy in te
rms of a quantum field theory is (nearly) universally accepted and detaile
d properties of the duality underpin numerous active research directions.
However\, a precise numerical agreement between microscopic and macroscopi
c entropies for black holes in AdS faced challenges that were only recentl
y addressed. We discuss new results and compare them with familiar ones fr
om AdS(3).\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/7/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Sean Hartnoll (Stanford)
DTSTART:20200622T210000Z
DTEND:20200622T220000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/8
DESCRIPTION:Title: Classical aspects of the black hole interior\nby Sean Hartn
oll (Stanford) as part of SITP seminar\n\n\nAbstract\nGeneric classical bl
ack hole interiors will be highly inhomogeneous and complicated. However\,
most holographic studies of the interior start from simple geometries suc
h as AdS-Schwarzschild or AdS-Reissner-Nordstrom. These have rather specif
ic singularity structures and AdS-RN has an inner Cauchy horizon at which
classical predictability breaks down. As we seek to understand the quantum
gravitational fate of black hole interiors\, and to understand the hologr
aphic description of infalling observers\, it seems like a good idea to ma
ke sure that any lessons we learn are not tied to overly simple non-generi
c classical starting points. Within a holographic framework\, a simple and
natural step towards genericity can be made by deforming the boundary the
ory away from conformality. I will describe the effects that such deformat
ions have on the interior of neutral and charged black holes.\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/8/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Shinsei Ryu (U Chicago)
DTSTART:20200713T210000Z
DTEND:20200713T220000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/9
DESCRIPTION:Title: Entanglement negativity and reflected entropy after quantum que
nch in 2d CFTs\nby Shinsei Ryu (U Chicago) as part of SITP seminar\n\n
\nAbstract\nWe will discuss non-equilibrium dynamics of 2d conformal field
theories probed by\nthe time-dependence of entanglement negativity and re
flected entropy after quantum quench of\nvarious kinds. We will contrast t
wo paradigmatic pictures -- quasi-particle and membrane pictures --\nthat
can describe the time-evolutions of these quantities depending on whether
the underlying\ndynamics is non-chaotic or chaotic. While the propagation
of quantum entanglement in rational\nCFTs is described by the quasi-partic
le pictures\, that in holographic CFTs is described by\nthe membrane pictu
re.\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/9/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Hirosi Ooguri (Caltech)
DTSTART:20200727T210000Z
DTEND:20200727T220000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/10
DESCRIPTION:Title: Stringy Tidal Effects Near Black Hole Photon Spheres\nby H
irosi Ooguri (Caltech) as part of SITP seminar\n\n\nAbstract\nI will repor
t on my work in progress with Matthew Dodelson. Correlation functions of C
FT with a weakly coupled holographic dual have interesting singularities d
ue to null geodesics in the bulk dual. In my paper with Dodelson last year
\, we showed that certain Landau singularities in the bulk at zero tempera
ture are resolved in string theory by the Gross-Mende expansion of the wor
ldsheet. At finite temperature\, we find that a black hole photon sphere
causes null singularities that are contrary to our expectations for CFT.
We show how these singularities are resolved in string theory by tidal eff
ects on the worldsheet\, which are enhanced near the null geodesics.\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/10/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Kevin Costello (Perimeter Institute)
DTSTART:20200803T210000Z
DTEND:20200803T220000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/11
DESCRIPTION:Title: Integrable field theories from four-dimensional gauge theory\nby Kevin Costello (Perimeter Institute) as part of SITP seminar\n\n\nA
bstract\nI will discuss aspects of my work with Yamazaki\, Witten\, Stefan
ski\, and Gaiotto which gives a unified construction of two-dimensional in
tegrable field theories and string theories from a certain four-dimensiona
l gauge theory.\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/11/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Juan Maldacena (IAS)
DTSTART:20200810T210000Z
DTEND:20200810T220000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/12
DESCRIPTION:Title: Bra-ket wormholes in gravitationally prepared states\nby J
uan Maldacena (IAS) as part of SITP seminar\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/12/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Eva Silverstein (Stanford)
DTSTART:20200831T210000Z
DTEND:20200831T220000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/13
DESCRIPTION:Title: The positive potential of negative curvature\nby Eva Silve
rstein (Stanford) as part of SITP seminar\n\n\nAbstract\nThis talk will de
scribe a new mechanism under development for accelerated expansion in the
generic case of negative-curvature compactifications of string/M theory (b
ased on work in progress with B. De Luca and G. Torroba). Hyperbolic manif
olds are well-studied mathematically\, with an important rigidity property
at fixed volume above dimension 2. They exhibit precise generalizations o
f string dualities and connect to other areas of the landscape. M theory o
n a fiducial hyperbolic manifold with asymmetric cusp cross section\, alon
g with its automatically generated Casimir energy and a single source (7-f
orm flux) contains an immediate 3-term structure for volume stabilization.
After bounding residual tadpoles from spatial variations of the Casimir e
nergy\, we study the detailed internal equations of motion and off-shell e
ffective potential as formulated by M. Douglas. We derive a Maldacena-Nune
z style no-go theorem for Anti-de Sitter extrema for a range of parameters
\, observe that standard integrated inequalities are all consistent with d
e Sitter solutions\, and discuss smooth internal field configurations with
small slow roll parameters. Both human and artificial neural networks --
including novel optimization methods via Born-Infeld dynamics and loss fun
ctions built from slow roll parameters -- contribute to the analysis\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/13/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Alexey Milekhin (UCSB)
DTSTART:20200928T210000Z
DTEND:20200928T220000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/14
DESCRIPTION:Title: quantum error correction and large N\nby Alexey Milekhin (
UCSB) as part of SITP seminar\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/14/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Lorenz Eberhardt (IAS)
DTSTART:20201019T210000Z
DTEND:20201019T220000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/15
DESCRIPTION:Title: Partition functions of the tensionless string\nby Lorenz E
berhardt (IAS) as part of SITP seminar\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/15/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Netta Engelhardt (MIT)
DTSTART:20201012T210000Z
DTEND:20201012T220000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/16
DESCRIPTION:Title: Free Energy from Replica Wormholes\nby Netta Engelhardt (M
IT) as part of SITP seminar\n\n\nAbstract\nRecent developments on the blac
k hole information paradox have shown that Euclidean wormholes — so call
ed “replica wormholes’’ can dominate the von Neumann entropy as comp
uted by a gravitational path integral\, and that inclusion of these wormho
les results in a unitary Page curve. This development raises some puzzles
from the perspective of factorization\, and has raised questions regarding
what the gravitational path integral is computing. In this talk\, I will
focus on understanding the relationship between the gravitational path int
egral and the partition function via the gravitational free energy (more g
enerally the generating functional). A proper computation of the free ener
gy requires a replica trick distinct from the usual one used to compute th
e entropy. I will show that in JT gravity there is a regime where the free
energy computed without replica wormholes is pathological. Interestingly\
, the inclusion of replica wormholes is not quite sufficient to resolve th
e pathology: an alternative analytic continuation is required. I will disc
uss the implications of this for various interpretations of the gravitatio
nal path integral (e.g. as computing an ensemble average) and also mention
some parallels with spin glasses.\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/16/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Leonardo Senatore (Stanford University)
DTSTART:20201005T210000Z
DTEND:20201005T220000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/17
DESCRIPTION:Title: A de-Sitter no-hair theorem for spacetimes with isometry group
forming two-dimensional orbits\nby Leonardo Senatore (Stanford Univer
sity) as part of SITP seminar\n\n\nAbstract\nI present how some numerical
and analytical general relativity techniques allow us to show how inflatio
n\, or a local region of de Sitter space\, gets started notwithstanding ve
ry inhomogeneous initial conditions and the potential formation of localiz
ed singularities.\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/17/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Petr Horava (UC Berkeley)
DTSTART:20201026T210000Z
DTEND:20201026T220000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/18
DESCRIPTION:Title: Large N Expansion and String Theory Out of Equilibrium\nby
Petr Horava (UC Berkeley) as part of SITP seminar\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/18/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Sung-Sik Lee (McMaster University)
DTSTART:20201116T220000Z
DTEND:20201116T230000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/19
DESCRIPTION:Title: A model of quantum gravity with emergent spacetime\nby Sun
g-Sik Lee (McMaster University) as part of SITP seminar\n\n\nAbstract\nWe
present a model of quantum gravity in which dimension\, topology and geome
try of spacetime are collective dynamical variables that describe the patt
ern of entanglement of underlying quantum matter. As spacetime with arbitr
ary dimensions can emerge\, the spacetime gauge symmetry is generalized to
a group that includes diffeomorphisms in general dimensions. The gauge sy
mmetry obeys a first-class constraint operator algebra\, and is reduced to
a generalized hypersurface deformation algebra in states that exhibit cla
ssical spacetimes. In the semi-classical limit\, we find a saddle-point so
lution that describes a series of (3+1)-dimensional de Sitter-like spaceti
mes with the Lorentzian signature bridged by Euclidean spaces in between.
Fluctuations of the collective variables are described by bi-local fields
that propagate in the spacetime set up by the saddle-point configuration o
f the collective variables.\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/19/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Alejandra Castro (University of Amsterdam)
DTSTART:20201130T220000Z
DTEND:20201130T230000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/20
DESCRIPTION:Title: The Spectrum of Near-Extremal Rotating Black Holes\nby Ale
jandra Castro (University of Amsterdam) as part of SITP seminar\n\n\nAbstr
act\nIn this talk\, I will revisit the spectrum of gravitational perturbat
ions of extremal rotating black holes\, with emphasis on the Kerr solution
. The goal is to identify and describe the modes that encode the dynamics
of Jackiw-Teitelboim gravity\, aka the JT sector\, which is expected to ac
count for the deviations away from extremality. For rotating solutions thi
s sector contains new features relative to their charged cousins that I wi
ll discuss. If time allows\, I will also present the analysis for a 5D rot
ating black hole\, where the analysis can be done at a non-linear level wi
th analytic control.\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/20/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Vijay Balasubramanian (University of Pennsylvania)
DTSTART:20201102T220000Z
DTEND:20201102T230000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/21
DESCRIPTION:Title: Knitting wormholes by entanglement in supergravity\nby Vij
ay Balasubramanian (University of Pennsylvania) as part of SITP seminar\n\
n\nAbstract\nWe construct a single-boundary wormhole geometry in type IIB
supergravity by perturbing two stacks of N extremal D3-branes in the deco
upling limit. The solution interpolates from a two-sided planar AdS-Schwar
zschild geometry in the interior\, through a harmonic two-center solution
in the intermediate region\, to an asymptotic AdS space. The construction
involves a CPT twist in the gluing of the wormhole to the exterior throats
that gives a global monodromy to some coordinates\, while preserving orie
ntability. The geometry has a dual interpretation in $\\mathcal{N}=4\,\\\;
SU(2N)$ Super Yang-Mills theory in terms of a Higgsed $SU(2N) \\to S(U(N)
\\times U(N))$ theory in which $\\mathcal{O}(N^2)$ degrees of freedom in e
ach $SU(N)$ sector are entangled in an approximate thermofield double stat
e at a temperature much colder than the Higgs scale. We argue that the sol
ution can be made long-lived by appropriate choice of parameters\, and com
ment on mechanisms for generating traversability. We also describe a cons
truction of a double wormhole between two universes.\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/21/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Emil Martinec (UChicago)
DTSTART:20210125T220000Z
DTEND:20210126T000000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/22
DESCRIPTION:Title: In Pursuit of the Hirsute: Finding Fuzz Around Black Holes
\nby Emil Martinec (UChicago) as part of SITP seminar\n\n\nAbstract\nAn un
derstanding of black hole microstructure – where and how they store and
release information – remains elusive. One place to look is near extrem
ality where these structures might reveal themselves\, and (super)symmetry
might help tame strong dynamics. This talk provides an overview of the f
uzzball program\, which broadly speaking is an ongoing investigation of th
e sorts of ingredients from string theory – both geometrical and stringy
– that are involved in extremal and near-extremal black hole microstruc
ture.\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/22/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Slava Rychkov (IHES)
DTSTART:20210201T190000Z
DTEND:20210201T210000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/23
DESCRIPTION:Title: Replicas and RG: case study of Random Field Ising Model\nb
y Slava Rychkov (IHES) as part of SITP seminar\n\n\nAbstract\nRandom Field
Ising Model is the classical Ising model with added quenched disorder (ma
gnetic impurities). This model has a second-order phase transition. For di
mension D close to the upper critical dimension 6\, the phase transition i
s described by a Parisi-Sourlas non-unitary supersymmetric CFT\, and has t
he same critical exponents as the non-disordered Ising model in D-2 dimens
ions. For lower D supersymmetry and dimensional reduction are lost\, but w
hy? Elucidating this from the RG point of view was an open problem for man
y years. I will describe recent progress achieved in arXiv:1912.01617\, ar
Xiv:2009.10087 (joint work with Apratim Kaviraj and Emilio Trevisani).\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/23/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Jorge Kurchan (ENS Paris)
DTSTART:20210208T220000Z
DTEND:20210209T000000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/24
DESCRIPTION:Title: An unexpected bridge between Black Holes and glasses\nby J
orge Kurchan (ENS Paris) as part of SITP seminar\n\n\nAbstract\nThe Sachde
v-Ye-Kitaev model has been recognized in the past few years as a simple mo
del having the symptoms of Black Holes and holography. Central to this cor
respondence is an emergent time-reparametrization invariance that appears
in the low-temperature\, slow dynamic limit. Glasses were long ago recogni
zed as having the same symmetry\, and for exactly the same formal reasons:
the slowness of the dynamics makes kinetic terms negligible. More recentl
y\, it has been realized that this symmetry is not merely an accident: it
is a necessary condition for both the Parisi (replica) construction and t
he corresponding dynamic picture to be consistent. Indeed\, as I will show
\, two systems brought into infinitesimal contact have to be able to oper
ate a large rearrangement of their timescales in order to match into a joi
nt solution of the same general form. It is also amusing to see that two g
lasses brought into contact develop a first-order transition in the temper
ature-interaction plane\, as do two SYK models.\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/24/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Joao Penedones (EPFL Lausanne)
DTSTART:20210308T190000Z
DTEND:20210308T210000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/25
DESCRIPTION:Title: Bootstrapping Effective Field Theories: pions and supergravito
ns\nby Joao Penedones (EPFL Lausanne) as part of SITP seminar\n\n\nAbs
tract\nI will review the (numerical) S-matrix Bootstrap approach to scatte
ring amplitudes. In particular\, I will explain how this approach can be u
sed to bound the space of Wilson coefficients in Effective Field Theories
(EFT). I will discuss two notable examples: the chiral lagrangian and supe
rgravity. Remarkably\, strongly coupled string theory seems to saturate th
e bounds imposed by Lorentz invariance\, unitarity and causality.\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/25/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Matias Zaldarriaga (IAS Princeton)
DTSTART:20210315T210000Z
DTEND:20210315T230000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/26
DESCRIPTION:by Matias Zaldarriaga (IAS Princeton) as part of SITP seminar\
n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/26/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Sameer Murthy (King's College London)
DTSTART:20210412T180000Z
DTEND:20210412T200000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/27
DESCRIPTION:Title: Black hole microstates from matrices\, and phases of super Yan
g-Mills theory\nby Sameer Murthy (King's College London) as part of SI
TP seminar\n\n\nAbstract\nOne question arising from the holographic princi
ple is: what are the microstates of black holes in the dual large-N field
theory? I will discuss recent progress on answering this question in canon
ical examples of the AdS/CFT correspondence (e.g. 4d $N=4$ SYM/AdS$_5$ str
ing theory). The field theory model is an integral over $N \\times N$ unit
ary matrices with a certain action which counts supersymmetric states in f
our-dimensional super Yang-Mills theory. I will present analytical and num
erical analyses of the matrix model which show that the asymptotic growth
of states of the matrix model with large charges agrees precisely with tha
t of the dual black hole microstates. In particular\, I will introduce a d
eformation of the matrix model which allows us to find large-N saddle-poin
ts and the resultant phase structure. I will show that there is an infinit
e family of large-N saddle points\, one of which is identified with the bl
ack hole. The deformation is closely related to the Bloch-Wigner elliptic
dilogarithm\, a function introduced by number theorists.\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/27/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Yu-tin Huang (National Taiwan University)
DTSTART:20210503T210000Z
DTEND:20210503T230000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/29
DESCRIPTION:by Yu-tin Huang (National Taiwan University) as part of SITP s
eminar\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/29/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Junwu Huang (Perimeter)
DTSTART:20210510T210000Z
DTEND:20210510T230000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/30
DESCRIPTION:by Junwu Huang (Perimeter) as part of SITP seminar\n\nAbstract
: TBA\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/30/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Veronika Hubeny (UC Davis)
DTSTART:20210517T210000Z
DTEND:20210517T230000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/31
DESCRIPTION:Title: Holographic Entropy Cone from Marginal Independence\nby Ve
ronika Hubeny (UC Davis) as part of SITP seminar\n\n\nAbstract\nThis talk
will explain recent puzzling revelations in the ongoing efforts to obtain
a useful characterization of entanglement structure of geometric states in
a holographic CFT\, via the so-called holographic entropy cone (HEC). The
relations between subsystem entanglement entropies which delimit this con
e are known explicitly for only a rather coarse subdivision of the system
(specified by N spatial regions\, for up to N = 5). We argue that\, subjec
t to a certain graph theoretic conjecture\, the task of finding the HEC fo
r arbitrary N can be recast in terms of a much simpler combinatorial one w
hich effectively reduces to the connectivity of entanglement wedges. More
specifically\, the N-party HEC can be reconstructed by solving the hologra
phic marginal independence problem (HMIP) for a finer subdivision N′ ≥
N\, which technically amounts to identifying which extreme rays of this s
ubadditivity cone are realizable holographically. Curiously\, despite the
fact that subadditivity is a universal property which states that total co
rrelation cannot be negative\, the non-trivial facets of the HEC construct
ed therefrom nevertheless cannot be recast as correlation measures.\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/31/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Nina Holden (ETH Zürich)
DTSTART:20210524T170000Z
DTEND:20210524T183000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/32
DESCRIPTION:Title: Liouville quantum gravity in probability theory\nby Nina H
olden (ETH Zürich) as part of SITP seminar\n\n\nAbstract\nIn probability
theory\, Liouville quantum gravity (LQG) is a model for a random surface.
There are two main directions of study: random conformal geometry and Liou
ville conformal field theory. We will give an overview of some recent deve
lopments on LQG in probability theory.\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/32/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Renato Renner (ETH Zurich)
DTSTART:20210301T220000Z
DTEND:20210301T230000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/33
DESCRIPTION:Title: A thought experiment to test the range of validity of quantum
theory\nby Renato Renner (ETH Zurich) as part of SITP seminar\n\n\nAbs
tract\nQuantum theory is one of our most accurate theories ever when it co
mes to the description of small systems. It is therefore often assumed tha
t the theory can equally well be applied to large objects\, sometimes even
astronomical ones like black holes. In this talk I will present a thought
experiment that indicates that the range of validity of (current) quantum
theory may be limited. It shows that contradictions can arise when quantu
m theory is used to describe a system that is complex enough so that it co
uld itself contain users of quantum theory. (The talk is based on work wit
h Daniela Frauchiger and Nuriya Nurgalieva.)\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/33/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Jorge Santos (University of Cambridge)
DTSTART:20210426T170000Z
DTEND:20210426T183000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/34
DESCRIPTION:Title: AdS Euclidean Wormholes\nby Jorge Santos (University of Ca
mbridge) as part of SITP seminar\n\n\nAbstract\nWe explore the constructio
n and stability of asymptotically anti-de Sitter Euclidean wormholes in a
variety of models. In simple ad hoc low-energy models\, it is not hard to
construct two-boundary Euclidean wormholes that dominate over disconnected
solutions and which are stable (lacking negative modes) in the usual sens
e of Euclidean quantum gravity. Indeed\, the structure of such solutions t
urns out to strongly resemble that of the Hawking-Page phase transition fo
r AdS-Schwarzschild black holes\, in that for boundary sources above some
threshold we find both a 'large' and a 'small' branch of wormhole solution
s with the latter being stable and dominating over the disconnected soluti
on for large enough sources. We are also able to construct two-boundary Eu
clidean wormholes in a variety of string compactifications that dominate o
ver the disconnected solutions we find and that are stable with respect to
field-theoretic perturbations. However\, as in classic examples investiga
ted by Maldacena and Maoz\, the wormholes in these UV-complete settings al
ways suffer from brane-nucleation instabilities (even when sources that on
e might hope would stabilize such instabilities are tuned to large values)
. This indicates the existence of additional disconnected solutions with l
ower action. We discuss the significance of such results for the factoriza
tion problem of AdS/CFT.\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/34/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Micha Berkooz (Weizmann)
DTSTART:20210603T173000Z
DTEND:20210603T190000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/35
DESCRIPTION:Title: Multi-trace correlators in the SYK model and Non-geometric wor
mholes\nby Micha Berkooz (Weizmann) as part of SITP seminar\n\n\nAbstr
act\nWe consider the global fluctuations in the density of states of the S
YK model. The connected contributions to the moments are much larger than
the standard RMT correlations. We provide a diagrammatic description of th
e leading behavior of these connected moments in terms of 1PI cactus graph
s\, and derive a vector model of the couplings which reproduces these resu
lts. We generalize these results to the first subleading corrections\, and
to fluctuations of correlation functions. In either case\, the new set of
correlations are not associated with (and are much larger than) the ones
given by topological wormholes. The connected contributions that we discus
s are the beginning of an infinite series of terms\, associated with more
and more information about the ensemble of couplings\, which hints towards
the dual of a single realization. In particular\, we suggest that incorpo
rating them in the gravity description requires the introduction of new\,
lighter and lighter\, fields in the bulk with fluctuating boundary couplin
gs.\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/35/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Ana-Maria Raclariu (Perimeter Institute)
DTSTART:20211004T210000Z
DTEND:20211004T220000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/36
DESCRIPTION:Title: Progress in Celestial Holography\nby Ana-Maria Raclariu (P
erimeter Institute) as part of SITP seminar\n\n\nAbstract\nCelestial ampli
tudes describe scattering in a basis of boost eigenstates. In this basis\,
4-point massless scattering observables are functions of two variables: t
he sum over the boost weights $\\beta$ which is dual to the center of mass
energy\, and a cross ratio $z$ related to the bulk scattering angle. In t
his talk I will describe two aspects of the physics captured by the $\\bet
a$ and $z$ dependence. I will first show that the UV behavior of 4-point s
cattering is encoded in the analytic structure of celestial amplitudes in
the complex $\\beta$ plane. The residues of the poles at negative even int
eger $\\beta$ are related to coefficients of higher-dimension operators in
the low-energy effective action\, hence subject to positivity constraints
\, while poles at positive even integer $\\beta$ arise from UV asymptotics
. I will then show that the $z$ dependence contains information about the
celestial spectrum and three-point couplings. For massless scalar 4-point
scattering mediated by massive exchange\, the conformal blocks include mas
sive scalar states with positive integer conformal weights\, as well as in
termediate exchanges of spinning light-ray states.\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/36/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Ofer Aharony (Weizmann Institute of Science)
DTSTART:20211011T180000Z
DTEND:20211011T200000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/37
DESCRIPTION:Title: Towards an explicit theory of quantum gravity\nby Ofer Aha
rony (Weizmann Institute of Science) as part of SITP seminar\n\n\nAbstract
\nIn the first half of this colloquium I will review the problem of quantu
m gravity\, and how it is solved for quantum gravity in anti-de Sitter spa
ce by the AdS/CFT correspondence. I will give two examples of this corresp
ondence illustrating that unlike in most other dualities\, quantum effects
can be small on both sides of the duality at the same time. In the second
half I will present for one of these examples (the O(N) vector model) an
explicit construction of a quantum theory of gravity (based on 2011.06328
in collaboration with Shai Chester and Erez Urbach).\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/37/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Liam McAllister (Cornell University)
DTSTART:20211018T210000Z
DTEND:20211018T220000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/38
DESCRIPTION:Title: Small Cosmological Constants in String Theory\nby Liam McA
llister (Cornell University) as part of SITP seminar\n\n\nAbstract\nWe con
struct vacua of string theory in which all moduli are stabilized and the m
agnitude of the cosmological constant is exponentially small. The vacua a
re supersymmetric AdS_4 solutions in flux compactifications of type IIB st
ring theory on orientifolds of Calabi-Yau hypersurfaces. I will explain t
he advances in computing topological data in Calabi-Yau compactifications
that led to these solutions\, then discuss implications for the cosmologic
al constant problem. The vacuum energy is small because we ensure the exa
ct cancellation of all perturbative contributions\, through an explicit ch
oice of integer parameters determined by the topology and quantized fluxes
. The nonperturbative contributions that remain are exponential in these
integers. Finding cosmological constants of small magnitude in this lands
cape is exponentially easier than in Bousso-Polchinski landscapes. Extend
ing this approach to positive cosmological constants\, however\, is a diff
icult open problem.\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/38/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Wendy Freedman (University of Chicago)
DTSTART:20211025T210000Z
DTEND:20211025T220000Z
DTSTAMP:20260404T111322Z
UID:SITPseminar/39
DESCRIPTION:Title: The Hubble Tension: Is There Evidence for New Physics?\nby
Wendy Freedman (University of Chicago) as part of SITP seminar\n\n\nAbstr
act\nAn important and unresolved question in cosmology today is whether th
ere is new physics that is missing from our current standard Lambda Cold D
ark Matter (LCDM) model. Recent measurements of the Hubble constant\, Ho -
- based on Cepheids and Type Ia supernovae (SNe) -- are discrepant at the
4-5-sigma level with values of Ho inferred from measurements of fluctuatio
ns in the cosmic microwave background (CMB). The latter assumes LCDM\, and
the former assumes that systematics have been fully accounted for. If rea
l\, the current discrepancy could be signaling a new physical property of
the universe. I will present new results based on an independent calibrati
on of SNe Ho based on measurements of the Tip of the Red Giant Branch (TRG
B). The TRGB marks the luminosity at which the core helium flash in low-ma
ss stars occurs\, and provides an excellent standard candle. Moreover\, th
e TRGB method is less susceptible to extinction by dust\, to metallicity e
ffects\, and to crowding/blending effects than Cepheid variable stars. I
will address the current uncertainties in both the TRGB and Cepheid dist
ance scales\, as well as discuss the current tension in Ho and whether the
re is need for additional physics beyond the standard LCDM model.\n
LOCATION:https://stable.researchseminars.org/talk/SITPseminar/39/
END:VEVENT
END:VCALENDAR