2.0-//132.68.74.185//NONSGML kigkonsult.se iCalcreator 2.26.9//GREGORIANPUBLISHhttps://phsites.technion.ac.il/stringsAsia/JerusalemAsia/JerusalemAsia/Jerusalem2021-10-31T02:00:002022-10-30T02:00:002023-10-29T02:00:00IST+03:00+02:002022-03-25T02:00:002023-03-24T02:00:00IDT+02:00+03:001q1eb9cb7bqvkb53qcdkc7u85c@google.com2022-05-22T19:32:56ZNo seminar – elections2021-03-232021-03-24en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/no-seminar-elections/6oimsaf4tjdr7eh28955jeadg6@google.com2022-05-22T19:32:56ZNo seminar – Passover2021-03-302021-03-31en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/no-seminar-passover/7g4bs7qbtmufuafu4usbvaf55m@google.com2022-05-22T19:32:56ZNo seminar – Erev Yom Hazikaron2021-04-132021-04-14en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/no-seminar-erev-yom-hazikaron/72iv4eimbg25u9bschq939higm@google.com2022-05-22T19:32:56ZNo seminar – Strings 20212021-06-222021-06-23en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/no-seminar-strings-2021-2/3tken4d7gcn8ukial7qt0t2lvd@google.com2022-05-22T19:32:56ZNo seminar – Strings 20212021-06-292021-06-30en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/no-seminar-strings-2021/4mqnm7epd8cd64mcl4utoo8k51@google.com2022-05-22T19:32:56ZNathan Seiberg (IAS)<p>Title: Anomalies in the Space of Coupling Constants</p>
<p>Abstract:<br />
It is customary to couple a quantum system to external classical fields. One application is to couple the global symmetries of the system (including the Poincare symmetry) to background gauge fields (and a metric for the Poincare symmetry). Failure of gauge invariance of the partition function under gauge transformations of these fields reflects ‘t Hooft anomalies. It is also common to view the ordinary (scalar) coupling constants as background fields, i.e. to study the theory when they are spacetime dependent. We will show that the notion of ‘t Hooft anomalies can be extended naturally to include these scalar background fields. Just as ordinary ‘t Hooft anomalies allow us to deduce dynamical consequences about the phases of the theory and its defects, the same is true for these generalized ‘t Hooft anomalies. Specifically, since the coupling constants vary, we can learn that certain phase transitions must be present. We will demonstrate these anomalies and their applications in simple pedagogical examples in one dimension (quantum mechanics) and in some two, three, and four-dimensional quantum field theories. </p>Asia/Jerusalem2019-05-28T10:30:00Asia/Jerusalem2019-05-28T11:30:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/nathan-seiberg-ias/7qsvj76fd9q2a6l7cr7hatf8c0@google.com2022-05-22T19:32:56ZLeopoldo Pando Zayas (Michigan)<p> Subleading Microstate Counting of AdS_4 Black Hole Entropy </p>
<p>I will describe how within eleven dimensional supergravity one can compute the logarithmic correction to the Bekenstein-Hawking entropy of certain magnetically charged asymptotically AdS_4 black holes with arbitrary horizon topology. The result perfectly agrees with the dual field theory computation of the topologically twisted index in ABJM theory and in certain theories obtained from M5 wrapping a hyperbolic 3-manifold.</p>Asia/Jerusalem2019-05-28T12:00:00Asia/Jerusalem2019-05-28T13:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/leopoldo-pando-zayas-michigan/0d3grimv9clhcr1veeg0u2scp2@google.com2022-05-22T19:32:56ZDio Anninos (King’s College London)<p>Title: Sphere partition functions and de Sitter space</p>
<p>Abstract: We consider the partition function of quantum fields on the Euclidean sphere, and its relation to quantum fields on de Sitter space. We express the sphere partition function in terms of group characters of the de Sitter group, providing a general expression for arbitrary spin and mass. We apply our results to a theory with an infinite tower of massless higher spin fields, which is the linearised spectrum of Vasiliev theory.</p>Asia/Jerusalem2019-06-04T10:30:00Asia/Jerusalem2019-06-04T11:30:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/dio-anninos-kings-college-london/661il9skro09b13dbueoi2gj0l@google.com2022-05-22T19:32:56ZMatti Jarvinen (Utrecht)<p>Neutron star physics from holographic QCD</p>
<p>Gauge/gravity duality can be used to study QCD at high densities and low<br />
temperatures where many other theoretical tools do not work. In<br />
particular one may constrain the equation of state of QCD matter in<br />
neutron star cores, which currently has large theoretical uncertainties.<br />
I will review recent progress on this topic. Bottom-up models which are<br />
carefully fitted to available data suggest that the equation of state is<br />
stiff (i.e., the speed of sound is high) in the nuclear matter phase and<br />
soft (i.e, the speed of sound is low) in the quark matter phase. The two<br />
phases are separated by a strong first order phase transition, which<br />
makes quark matter cores of neutron stars unstable. This picture agrees<br />
with current experimental constraints from LIGO/Virgo and from mass<br />
measurements of neutron star binaries.</p>Asia/Jerusalem2019-06-04T12:00:00Asia/Jerusalem2019-06-04T13:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/matti-jarvinen/61p6aj8gkuq20b0ov3qic0slrp@google.com2022-05-22T19:32:56ZSoumyadeep Chaudhuri<p>Title : Out of time ordered effective dynamics of a Brownian particle</p>
<p>Abstract : In this talk I will present the out of time ordered dynamics of a Brownian particle interacting with a thermal bath. To illustrate the features of this effective dynamics, I will describe a simple toy model where the bath comprises of two sets of harmonic oscillators coupled nonlinearly to the Brownian particle. Beginning with a Schwinger-Keldysh effective action of the particle, I will demonstrate its duality with a stochastic theory governed by a non-linear Langevin equation. This Langevin dynamics or the equivalent Schwinger-Keldysh effective theory is, however, inadequate for determining the Out-of-Time-Order Correlators (OTOCs) of the particle.This limitation can be overcome by extending the particle’s effective theory to a path integral formalism defined on a contour with multiple time-folds. This extension introduces some new effective couplings which are determined by the bath’s OTOCs. The couplings in this OTO effective theory satisfy some constraints due to microscopic reversibility and thermality of the bath. I will show that, from the point of view of the Langevin dynamics, these constraints lead to a generalised fluctuation-dissipation relation between a non-Gaussianity in the noise distribution and a thermal jitter in the particle’s damping coefficient.</p>Asia/Jerusalem2019-10-22T10:30:00Asia/Jerusalem2019-10-22T11:30:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/shlomo-razamat-3/5lohfit82pof26bdm2p7ak5s03@google.com2022-05-22T19:32:56ZSergei Dubovsky<p>Title: “Integrability from Confinement”</p>
<p>Abstract: </p>
<p>I will argue that high energy dynamics on the worldsheet of confining strings is integrable and illustrate this point using two examples.<br />
The first is a pure Yang—Mills theory in two spatial dimensions. There this logic allows one to obtain a prediction for quantum numbers<br />
of all glueballs. I will present results of a dedicated lattice simulation which confirm this prediction. The second example is an adjoint QCD in one spatial dimension.<br />
There this logic leads to a “zigzag model”—a remarkably simple novel integrable relativistic $N$-body system. I will prove the Liouville integrability<br />
of the zigzag model by presenting an explicit construction of the corresponding conserved charges.<br />
This model describes the $N$-particle subsector of a $Tbar{T}$-deformed massless fermion and<br />
suggests a natural setting for constructing off-shell observables in $Tbar{T}$-deformed theories.</p>Asia/Jerusalem2019-10-22T12:00:00Asia/Jerusalem2019-10-22T13:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/sergei-dubovsky/3bcn5en350tbdqdvo164q7f283@google.com2022-05-22T19:32:56ZLampros Lamprou (MIT)<p>“Holographic order from modular chaos”</p>Asia/Jerusalem2019-11-05T10:30:00Asia/Jerusalem2019-11-05T11:30:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/sergei-razamat/0dnlieuv5nge6mpkppdkibq9e7@google.com2022-05-22T19:32:56ZGiuseppe Mussardo (SISSA)<p>Title: Generalised Riemann Hypothesis, Random Time Series and Normal Distributions</p>
<p>Abstract: L functions based on Dirichlet characters are natural generalizations of the Riemann zeta function: they both have series representations and satisfy an Euler product representation, i.e. an infinite product taken over prime numbers. We address the Generalized Riemann Hypothesis relative to the non-trivial complex zeros of the Dirichlet L functions by studying the possibility to enlarge the original domain of convergence of their Euler product. This leads us to analyse the asymptotic behaviour of particular series on primes: although deterministic, these series have pronounced stochastic features which make them analogous to random time series. For non-principal characters, we show that, in view of the Dirichlet theorem on the equidistribution of reduced residue classes modulo q and the Lemke Oliver-Soundararajan result on the distribution of pairs of residues on consecutive primes, these series present a universal diffusive random walk behavior with critical exponent ½.</p>Asia/Jerusalem2019-11-05T12:00:00Asia/Jerusalem2019-11-05T13:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/giuseppe-mussardo/3tikhba10rt873k46c9q7aug78@google.com2022-05-22T19:32:56ZShlomo Razamat<p>title: N=1 conformal dualities</p>
<p>abstract: We consider on one hand the possibility that a supersymmetric N = 1 conformal gauge theory has a strongly coupled locus on the conformal manifold at which a different, dual, conformal gauge theory becomes a good weakly coupled description. On the other hand we discuss the possibility that strongly coupled theories, e.g. SCFTs in class S, having exactly marginal N = 1 deformations admit a weakly coupled gauge theory description on some locus of the conformal manifold. We present a simple algorithm to search for such dualities and discuss several concrete examples. In particular we find conformal duals for N = 1 SQCD models with G2 gauge group and a model with SU(4) gauge group in terms of simple quiver gauge theories. We also find conformal weakly coupled quiver theory duals for a variety of class S theories: T4, R0,4, R2,5, and rank 2n Minahan-Nemeschansky E6 theories. Finally we derive conformal Lagrangians for four dimensional theories obtained by compactifying the E-string on genus g > 1 surface with zero flux. The pairs of dual Lagrangians at the weakly coupled loci have different symmetries which are broken on a general point of the conformal manifold. We match the dimensions of the conformal manifolds, symmetries on the generic locus of the conformal manifold, anomalies, and supersymmetric indices. The simplicity of the procedure suggests that such dualities are ubiquitous.</p>Asia/Jerusalem2019-11-26T10:30:00Asia/Jerusalem2019-11-26T11:30:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/shlomo-razamat-5/01issq4ups20e2mho9vm6anu6t@google.com2022-05-22T19:32:56ZVladimir Rosenhaus (IAS)<p>Title: Integrability and Renormalization under TT¯</p>
<p>Abstract: Smirnov and Zamolodchikov recently introduced a new class of two-dimensional quantum field theories, defined through a differential change of any existing theory by the determinant of the stress-tensor. From this TT¯ flow equation one can find a simple expression for both the energy spectrum and the S-matrix of the TT¯ deformed theories. Our goal is to find the renormalized Lagrangian of the TT¯ deformed theories. In the context of the TT¯ deformation of an integrable theory, the deformed theory is also integrable and, correspondingly, the S-matrix factorizes into two-to-two S-matrices. One may thus hope to be able to extract the renormalized Lagrangian from the S-matrix. We do this explicitly for the TT¯ deformation of a free massive scalar, to second order in the deformation parameter. Once one has the renormalized Lagrangian one can, in principle, compute all other observables, such as correlation functions. We briefly discuss this, as well as the relation between the renormalized Lagrangian, the TT¯ flow equation, and the S-matrix.</p>Asia/Jerusalem2019-11-26T12:00:00Asia/Jerusalem2019-11-26T13:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/vladimir-rosenhaus-ias-2/64ngu1ja3huv6c98bm3594421n@google.com2022-05-22T19:32:56ZNele Callebaut<p>Title: TTbar-deformed CFT as a non-critical string</p>
<p>Abstract: </p>
<p>I will present a non-critical world-sheet string theory action as a proposed description of the TTbar deformation of a 2D CFT with general central charge. This talk will be based on 1910.13578. </p>Asia/Jerusalem2019-12-10T10:30:00Asia/Jerusalem2019-12-10T11:30:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/nele-callebaut-2/3fm5rkqtvcfj35ddg3m8f6ek2j@google.com2022-05-22T19:32:56ZMisha Smolkin<p>Title: Vector model in higher dimension</p>
<p>Abstract: I will explain why we study UV behaviour of the O(N) vector<br />
model with quartic interaction in 4 < d < 6 dimensions and present a<br />
number of calculations related to the CFT data of the model at the UV<br />
fixed point.</p>Asia/Jerusalem2019-12-10T12:00:00Asia/Jerusalem2019-12-10T13:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/misha-smolkin/2qcom6m2v5qogs8oeme4rhe848@google.com2022-05-22T19:32:56ZZvi Bern (UCLA)<p>Title: From Scattering Amplitudes to Gravitational Waves</p>
<p>Abstract: The remarkable detection of gravitational waves by the LIGO/Virgo<br />
collaboration has opened a new window into the cosmos. In this<br />
colloquium we explain how particle theorists can help out with<br />
high-precision calculations of effective Hamiltonians for predicting<br />
gravitational-wave emission from compact astrophysical objects.<br />
We explain reamarkable adavances in our ability to compute<br />
scattering amplitudes in quantum gravity based on ideas such as the<br />
duality between color and kinematics, double-copy relations and<br />
generalized unitarity. We then show how these ideas can be harnessed<br />
using modern ideas in effective field theory to obtain new and<br />
difficult to obtain general relativity corrections to the problem of<br />
black hole or neutron star inspirals.</p>Asia/Jerusalem2019-12-24T10:30:00Asia/Jerusalem2019-12-24T11:30:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/zvi-bern-ucla/584srvg5efquglg73jr31gvt5r@google.com2022-05-22T19:32:56ZAnshuman Dey<p>Title : Chern-Simons-Matter Duality and Large-N Phase Diagram</p>
<p>Abstract : Pure Chern-Simons (CS) theory looks quite boring at a first glance. However, the theory becomes highly interesting and rich dynamics come out of it once we couple it to dynamical matter fields. It is quite remarkable that the large-N limit of this matter CS theory is exactly solvable. This led to the understanding of the fact that CS gauged fundamental regular (free) fermion theories and CS gauged fundamental critical (Wilson-Fisher) boson theories are not different but secretly the same theory, related by the level-rank duality. In this talk, I will show the extension of this duality when the boson field gets condensed triggering the Higgs mechanism. In the next step, extending this duality to the regular boson/critical fermion case, we will compute the exact quantum effective potential of the regular boson theory and explore the large-N phase diagram of this theory.</p>Asia/Jerusalem2019-12-24T12:00:00Asia/Jerusalem2019-12-24T13:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/anshuman-dey/67rgrop9t2s9ubum4918vlmjdh@google.com2022-05-22T19:32:56ZYaron Oz<p>“Turbulence, CFT and Random Geometry”</p>
<p>We propose a field theory description of steady state incompressible fluid turbulence at the inertial range of scales in a general number of space dimensions.<br />
The theory consists of a Kolmogorov linear scaling mean field theory dressed by a Nambu-Goldstone dilaton mode that induces a random measure on the inertial range.<br />
We derive a KPZ-type formula for the anomalous scalings of the velocity structure functions, the velocity gradients and the local energy dissipation, and relate the dimensionless intermittency parameter to the boundary conformal anomaly.</p>Asia/Jerusalem2020-01-14T10:30:00Asia/Jerusalem2020-01-14T11:30:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/yaron-oz/1j5q18je7kpcgmq26rica8rk1c@google.com2022-05-22T19:32:56ZChristoph Uhlemann (UCLA)<p>Title: Exact results for 5d SCFTs with holographic duals in Type IIB</p>
<p>Abstract: Five-dimensional superconformal field theories (5d SCFTs) play an interesting role in the general understanding of quantum field theory. They provide strongly-coupled UV fixed points with remarkable features for many perturbatively non-renormalizable gauge theories, and upon compactification they provide new insights into lower-dimensional theories. In this talk recent progress in the holographic and large-N field theory understanding of 5d SCFTs engineered by 5-brane webs in Type IIB string theory will be discussed.</p>Asia/Jerusalem2020-01-14T12:00:00Asia/Jerusalem2020-01-14T13:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/christoph-uhlemann-ucla/3dl6v8jh8etvcthi5jprabqilr@google.com2022-05-22T19:32:56ZHee-Cheol Kim (POSTECH, Korea)<p>Title: Branes and the Swampland</p>
<p>Abstract: In this talk, I will discuss consistency of N=(1,0) supergravity theories in 10d and in 6d by using 1/2 BPS string probes. Such string probes are expected to exist due to completeness of the spectrum of charged branes in a gravitational theory.I will show that some of the theories with N=(1,0) supersymmetry in 10d and 6d, which are otherwise consistent looking, belong to the Swampland by showing that the central charge on the string probes in those gravity theories are too small to host unitary representationsof the current algebra for the bulk gauge symmetries.</p>Asia/Jerusalem2020-02-04T10:30:00Asia/Jerusalem2020-02-04T11:30:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/hee-cheol-kim-postech-korea/1qnr4cfj4nefdvve8t19balcen@google.com2022-05-22T19:32:56ZShai Chester<p><span><br /><span>Title “AdS/CFT at finite string coupling”</span></p>
<p><span><br /></span><br /><span>Abstract<br /></span><br /><span>We consider the S-matrix in </span><span>Type IIB/IIA string theory, and compare it to correlators of the stress tensor multiplet in various holographic CFTs. On flat space, the leading small momentumcorrections to these S-matrices are protected and known at finite string coupling. At finite string coupling, </span><span>Type IIB on</span> <span>AdS_5 x S_5 is dual to</span><span> 4dN=4 SYM at large N and finite complexified coupling tau, while Type IIA on</span><span> AdS_4 x S^7/Z_k is dual to</span><span> 3d ABJM with Chern-Simons level k at large N and fixed N/k^5. In each case, we computethe CFT correlator to several orders in 1/N using supersymmetric localization, and find that it matches the known S-matrix in the flat space limit, which is the first non-perturbative (in string coupling) check of AdS/CFT. In the Type IIB case, the 1/N coefficientsare modular functions of tau under S-duality, which receive infinite instanton corrections. In the Type IIA case, the 1/N coefficients receive no instanton corrections, and interpolate from M-theory at small k (large string coupling) to Type IIA at large k(weak string coupling)</span></span></p>Asia/Jerusalem2020-02-04T12:00:00Asia/Jerusalem2020-02-04T13:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/shai-chester/6gc8109i11b3epfpueggpfq1q4@google.com2022-05-22T19:32:56ZRomuald Janik<p>Title: Dynamics near a holographic first order phase transition</p>
<p>Abstract:</p>
<p>In this talk I will discuss our recent work on time dependent dynamics for theories with a first order phase transition using a holographic description. I will make a brief review of our previous work on holographic phase separation which leads to a coupleof questions. In particular I will analyze the collisions and merging of domains of different phases, boost invariant evolution and some conclusions for the future study of the dynamics of a confinement-deconfinement transition.</p>Asia/Jerusalem2020-02-11T10:30:00Asia/Jerusalem2020-02-11T11:30:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/romuald-janik/4ohu1rj7ln09c5jpg751hrmhg0@google.com2022-05-22T19:32:56ZEly Kovetz<p>Title: The “Hubble Tension”: a growing disagreement between early and late Universe observations</p>
<p>Abstract: </p>
<p>There are two approaches to estimating the current expansion rate of the Universe, which is parametrised by the Hubble constant H0. One attempts to measure it directly (the most famous example of which relies on calibrating a distance ladder towards standard-candletype-Ia supernovae in our local cosmic neighbourhood). The other is to predict its value based on information from the distant early Universe (such as the baryon acoustic oscillation scale, which can be extracted from cosmic microwave background measurements)and assuming the standard cosmological model, known as ΛCDM. One of the most pressing mysteries in cosmology today is why H0 measurements based on these two approaches are growing in tension (the most recent assessments are up to ~5sigma discrepant), possiblyhinting at a failure of ΛCDM.<br />
I will describe the current status of different measurements of the expansion rate (based on a wide range of observables), point out their caveats and outline their prospects for improvement. From the theoretical point of view, I will motivate a usefulway of reframing the tension, and discuss the clues we have towards solving it with new physics beyond ΛCDM. </p>Asia/Jerusalem2020-02-11T12:00:00Asia/Jerusalem2020-02-11T13:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/ely-kovetz/39ufodjttephnhf5658obt26ik@google.com2022-05-22T19:32:56ZShinji Hirano, Wits university.<p>Title: Random boundary geometry and gravity dual of $Tbar{T}$ deformation<br />
Abstract: We study the random geometry approach to the $Tbar{T}$ deformation of 2d conformal field theory developed by Cardy and discuss its realization in a gravity dual. In this representation the gravity dual of the $Tbar{T}$ deformation becomes a straightforward translation of the field theory language and the dual geometry is AdS$_3$ or BTZ black holes without a finite cutoff but instead with random boundary diffeomorphisms, reflecting an increase of degrees of freedom in the flow to the UV by an irrelevant geometric $Tbar{T}$ operator. We streamline the method of computation and calculate the energy spectrum and the thermal free energy in a manner that can be directly translated into the gravity dual language. We further generalize this approach to correlation functions and reproduce the all-order result with universal logarithmic corrections computed by Cardy in a different method. Thus this version of gravity dual of the $Tbar{T}$ deformation works not only for the energy spectrum and the thermal free energy but also for correlation functions.</p>Asia/Jerusalem2020-02-25T10:30:00Asia/Jerusalem2020-02-25T11:30:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/shinji-hirano-wits-university/0er7g7220n1777ku0p2p727nf9@google.com2022-05-22T19:32:56ZUri Kol NYU<p>The title: “A new topological symmetry of asymptotically flat spacetimes”</p>
<p>I will show that asymptotically flat spacetimes are invariant, in addition to the BMS group, under a new dual supertranslation symmetry. The corresponding new conserved charges are akin to the large magnetic U(1) charges in QED and they reveal a rich topologicalstructure exhibited by the asymptotic metric as well as by the Hilbert space of asymptotic states. Among the results that I will describe in this talk are the construction of a gravitational-magnetic monopole solution analogous to the Wu-Yang monopole in QEDand the discovery of a new gravitational duality akin to electric-magnetic duality in field theory.</p>Asia/Jerusalem2020-02-25T11:30:00Asia/Jerusalem2020-02-25T12:30:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/uri-kol-nyu/3238fsfbmi3ucq6t8vgs9kbt1r@google.com2022-05-22T19:32:56ZSilviu Pufu, Princeton (Postponed due to corona)<p>Title: Instantons in five-dimensional O(N) vector models </p>
<p>Abstract: In this talk, I will review the construction of O(N) vector models above four dimensions, and explain why one might think that, in five dimensions, there should exist O(N)-invariant CFTs at sufficiently large N. However, a closer look at theseconstructions reveals that the CFTs are non-unitary because instanton effects lead to small imaginary parts of scaling dimensions and OPE coefficients.</p>Asia/Jerusalem2020-03-17T10:30:00Asia/Jerusalem2020-03-17T11:30:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/ramy-brustein-4/28jg4qsbm6uot5o98p235hb790@google.com2022-05-22T19:32:56ZSkura Schafer-Nameki, Oxford (Postponed due to corona)<p>Title: 5d SCFTs and Graphs </p>
<p>Abstract:<br />
I will give an overview of recent progress towards classifying 5d N=1 SCFTs. The main tool is the realization in terms of M-theory on singular Calabi-Yau three-folds, however we abstract the information about the UV fixed points into graphs, and explain howthese encode RG-flows between 5d SCFTs, weakly coupled descriptions as well as dualities.</p>Asia/Jerusalem2020-03-17T11:30:00Asia/Jerusalem2020-03-17T12:30:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/skura-schafer-nameki/566hvo8g72snr6s67l54gg1b50@google.com2022-05-22T19:32:56ZAsia/Jerusalem2020-03-31T10:30:00Asia/Jerusalem2020-03-31T11:30:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/victor-gorbenko-stanford/7i3viabfgakqvtfchfseg7h3f9@google.com2022-05-22T19:32:56ZSakura Schafer-Nameki, Oxford<p>Title: 5d SCFTs and Graphs</p>
<p>I will give an overview of recent progress towards classifying 5d N=1 SCFTs. The main tool is the realization in terms of M-theory on singular Calabi-Yau three-folds, however we abstract the information about the UV fixed points into graphs, and explain howthese encode RG-flows between 5d SCFTs, weakly coupled descriptions as well as dualities.</p>Asia/Jerusalem2020-03-31T11:30:00Asia/Jerusalem2020-03-31T12:30:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/avner-karasik-cambridge/527joup135vh5b638j9pt1ids2@google.com2022-05-22T19:32:56ZNathan Seiberg, IAS<p>Title:Continuum Quantum Field Theories for Fractons</p>
<p>Abstract: Starting with a lattice system at short distances, its long-distance behavior is captured by a continuum Quantum Field Theory (QFT). This description is universal, i.e. it is independent of most of the details of the microscopic system. Surprisingly, certain recently discovered lattice systems, and in particular models of fractons, seem to violate this general dogma. Motivated by this apparent contradiction, we will present exotic continuum QFTs that describe these systems.</p>
<p>This will be a zoom joint seminar. The link will be sent to the regular participants of the joint seminar. Other people who are interested to attend it send a message to </p>
<p><a href="mailto:cobi@tauex.tau.ac.il" id="ow505">cobi@tauex.tau.ac.il</a></p>Asia/Jerusalem2020-04-21T15:00:00Asia/Jerusalem2020-04-21T16:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/nathan-seiberg-ias-2/4t6a2ba89bqcu73lthbjp8p30h@google.com2022-05-22T19:32:56ZSlava Rychkov, IHES, Bures-sur Yvette<p> Slava Rychkov (IHES, Bures-sur-Yvette)</p>
<p>title:<br />Supersymmetry and its absence in the Random Field Ising Model.</p>
<p>Abstract:<br />We will discuss the phase transition in the Ising model with magnetic impurities. By one kind of lore, this leads to a non-unitary supersymmetric CFT with scalar supercharges (Parisi-Sourlas supersymmetry). By further lore, Parisi-Sourlas SCFTin D dimensions is equivalent to a non-SUSY CFT in D-2 dimensions. It is known that this story is not fully correct, but we will put some of it on firmer ground using non-perturbative CFT methods, and we will propose a scenario for why the full conjecture isfailing. Joint work with Apratim Kaviraj and Emilio Trevisani.</p>
<h2> </h2>
<h2> </h2>
<p>This will be a zoom joint seminar. The link will be sent to the regular participants of the joint seminar. Other people who are interested to attend it send a message to </p>
<p><a href="mailto:cobi@tauex.tau.ac.il">cobi@tauex.tau.ac.il</a></p>Asia/Jerusalem2020-05-05T11:30:00Asia/Jerusalem2020-05-05T12:30:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/slava-rychkov-ihes-ens/4f0pd6ra7ecda1fq4dahp21n0m@google.com2022-05-22T19:32:56ZTadashi Takayanagi, YITP Kyoto<p>title: Holographic Pseudo Entropy</p>
<p>abstract: In this talk, we will study a generalization of holographic entanglement entro<br />
py. This quantity is defined by a mininal area surface in an asymptoticaly AdS<br />
space with Euclidean time-dependence. We will give its CFT counterpart, which<br />
we call pseudo entropy. We will also provide quantum information theoretic in<br />
terpretations of this quantity in several specific examples of qubit systems,<br />
which help us to understand our results of pseudo entropy in CFTs and gravity<br />
duals. </p>Asia/Jerusalem2020-05-12T11:00:00Asia/Jerusalem2020-05-12T12:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/tadashi-takayanagi-yitp-kyoto/3215e6ltd0htfal4g4q6sjlo0p@google.com2022-05-22T19:32:56ZElias Kiritsis, Crete U., APC Paris<p>title: “Holographic renormalization group flows on curved manifolds and F-theorems” </p>
<p>Abstract: Holographic RG flows will be studied where the QFT is both on flat and curved manifolds, and their general structure will be analyzed.</p>
<p>Quantum phase transitions driven by curvature will be found and studied.</p>
<p>The results will be used to propose new F-functions in 3 dimensions that may be generalizable also to higher dimensions.</p>
<p>This will be a zoom joint seminar. The link will be sent to the regular participants of the joint seminar. Other people who are interested to attend it send a message to </p>
<p><a href="mailto:cobi@tauex.tau.ac.il" id="ow519">cobi@tauex.tau.ac.il</a></p>Asia/Jerusalem2020-05-19T11:00:00Asia/Jerusalem2020-05-19T12:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/elias-kiritsis-crete-u-apc-paris/0js5bb3a1hutkh6mqkp8p1frmu@google.com2022-05-22T19:32:56ZAmit Sever, Tau Cern<p>Title – An Analytical Toolkit for the S-matrix Bootstrap<br />
Abstract – Motivated by the success of the conformal bootstrap, we revisit the implications of elastic unitarity and extended analyticity for the S-matrix of unitary, relativistic, gapped theories in d>2 spacetime dimensions. We consider two natural expansion of the non-perturbative amplitude — the threshold and the large spin expansions, as well as the relation between them. Finally, we discuss the implication of these to the numerical S-matrix bootstrap.</p>Asia/Jerusalem2020-05-26T11:30:00Asia/Jerusalem2020-05-26T12:30:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/amit-sever-tau-cern/45um4ld11qkbcjb6hdfcdakm7s@google.com2022-05-22T19:32:56ZEran Palti BGU, MPI Munich<p style="margin-top:0;margin-bottom:0"><span style="font-size:16px;font-family:Calibri,Helvetica,sans-serif,Helvetica,EmojiFont,Apple Color Emoji,Segoe UI Emoji,NotoColorEmoji,Segoe UI Symbol,Android Emoji,EmojiSymbols">Title: </span>An overview of the Swampland</p>
<p style="margin-top:0;margin-bottom:0"><span style="font-size:16px;font-family:Calibri,Helvetica,sans-serif,Helvetica,EmojiFont,Apple Color Emoji,Segoe UI Emoji,NotoColorEmoji,Segoe UI Symbol,Android Emoji,EmojiSymbols">Abstract:The Swampland program aims at distinguishingeffective theories which can be consistently completed into quantum gravity in the ultraviolet from those which cannot. The main objective of this talk is to present an introduction to the field. I will also present a brief overview of some </span><font style="font-size:16px;font-family:Calibri,Helvetica,sans-serif,Helvetica,EmojiFont,Apple Color Emoji,Segoe UI Emoji,NotoColorEmoji,Segoe UI Symbol,Android Emoji,EmojiSymbols"><span style="font-size:12pt">recentwork which proposes and tests some Swampland constraints, specifically relating to scale separation in </span></font><font style="font-size:16px;font-family:Calibri,Helvetica,sans-serif,Helvetica,EmojiFont,Apple Color Emoji,Segoe UI Emoji,NotoColorEmoji,Segoe UI Symbol,Android Emoji,EmojiSymbols"><span style="font-size:12pt">anti-deSitter spaces and to the presence of gravitational instanton corrections in supersymmetric theories.</span></font></p>
<p style="margin-top:0;margin-bottom:0"></p>Asia/Jerusalem2020-06-02T11:30:00Asia/Jerusalem2020-06-02T12:30:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/eran-palti-bgu-mpi-munich/13pdh3246k1ndvcu5iu869db9f@google.com2022-05-22T19:32:56ZMasanori Hanada, ( Southampton U., Surrey U.<div style="font-size:17px;margin:0;line-height:normal">Title:</p>
<div style="font-size:17px;margin:0;line-height:normal">Color Confinement and Bose-Einstein Condensation</p>
<div style="font-size:17px;margin:0;min-height:20px;line-height:normal">
<div style="font-size:17px;margin:0;line-height:normal">Abstract: </p>
<div style="font-size:17px;margin:0;line-height:normal">We argue that partially-confined, partially-deconfined phase, in which SU(M) subgroup of SU(N) gauge group deconfines, exists between completely confined phase and completely deconfinedphases. In the weak-coupling regime, we describe this phase analytically, by using the techniques developed by Aharony and collaborators in 2003. (If time permits, we show the evidence at strong coupling as well, by using the Monte Carlo method.) Based on this”partial confinement” picture, we propose a unified description of color confinement in the large-N gauge theory and Bose-Einstein condensation (BEC) in the system of identical bosons. Indistinguishability associated with the symmetry group — SU(N) in gaugetheory, and S_N permutations in the system of identical bosons — is crucial for the formation of the condensed (confined) phase. We relate standard criteria, based on off-diagonal long range order (ODLRO) for BEC and the Polyakov loop for gauge theory. Theconstant offset of the distribution of the phases of the Polyakov loop corresponds to ODLRO. This viewpoint may have implications for confinement at finite N, and for quantum gravity via gauge/gravity duality. </p>Asia/Jerusalem2020-06-09T11:30:00Asia/Jerusalem2020-06-09T12:30:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/masanori-hanada-southampton-u-surrey-u/2qprpg6kb047d0qe9sqop1c9qa@google.com2022-05-22T19:32:56ZAsoke Sen, Harish-Chandra Res. Inst<p>D-instantons perturbation theory</p>Asia/Jerusalem2020-06-16T11:30:00Asia/Jerusalem2020-06-16T12:30:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/asoke-sen-harish-chandra-res-inst/4m7dpk42lfc7qgk2visrvek094@google.com2022-05-22T19:32:56ZDavid Tong, Cambridge<p>Title: Boundary Conditions for Chiral Fermions</p>
<p>Abstract: Iʼll describe boundary conditions for fermions in d=1+1,<br />
dimensions, using the framework of boundary conformal field theory. Iʼll<br />
explain how boundary states are classified by a mod 2 index, related to<br />
their SPT phase, describe how one can follow RG flows from one boundary<br />
state to another, and give a novel perspective on the Z_8 classification<br />
of d=2+1 SPT phases </p>Asia/Jerusalem2020-06-23T11:30:00Asia/Jerusalem2020-06-23T12:30:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/david-tong-cambridge/55smqkjeaeaq6joj6htk8p054s@google.com2022-05-22T19:32:56ZAbhijit Gadded<p>Title:</p>
<p>Modularity of supersymmetric partition functions</p>
<p>Abstract:</p>
<p>In this talk, I will present a novel modular property of 4d N=1<br />
supersymmetric partition functions of supersymmetric theories with R-symmetry. It is a generalization of the modular invariance of the supersymmetric partitionfunction of two-dimensional supersymmetric theories on a torus i.e. of the elliptic genus. It comes from requiring consistency of partitionfunctions under gluing and, among other things, can be used to rederive the supersymmetric Cardy formula for four-dimensional gaugetheories that has played a key role in computing the entropy of supersymmetric black holes.</p>Asia/Jerusalem2020-07-21T11:30:00Asia/Jerusalem2020-07-21T12:30:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/abhijit-gadded/3td0odltrcmpsbr1bq8hr7kha2@google.com2022-05-22T19:32:56ZEdward Witten<p>Title: Deformations of JT Gravity and Matrix Models,</p>
<p>Abstract: I will explain how the relation between two-dimensional JT gravity and a matrix model — that is a</p>
<p>random ensemble of quantum systems rather than a specific quantum system — can be generalized </p>
<p>when one perturbs the action of JT gravity to a more generic case. Based on arXiv:2006.13414.</p>
<p>See also arXiv:2006.11317 by Maxfield and Turiaci.</p>
<p>Anybody who is not on the list of the Israel string joint seminar and would like to listen to this seminar send your email to cobi@tauex.tau.ac.il and you will receive the zoom link</p>Asia/Jerusalem2020-08-04T16:00:00Asia/Jerusalem2020-08-04T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/edward-witten/3ng7jeutgnf09pd29snnkn2l9b@google.com2022-05-22T19:32:56ZZohar Komargodski<p>Title: “Non-Symmetries and 2-Dimensional QCD” ?Abstract :<br />
We will review the subject of “non-symmetries’’ or “defect symmetries.” We will argue that massless two dimensional QCD admits exponentially many such symmetries and we use them to prove deconfinement as well as to compute exactly the tension of thestring in the small mass limit. </p>Asia/Jerusalem2020-09-01T15:00:00Asia/Jerusalem2020-09-01T16:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/zohar-komargodski-3/7m7knk2dpqb2ie345crbc4403b@google.com2022-05-22T19:32:56ZJuan Maldacena<p>title: “Humanly traversable wormholes”</p>Asia/Jerusalem2020-09-08T16:00:00Asia/Jerusalem2020-09-08T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/juan-maldacena/11k9cfdor28oebf2dbe1ci9jiu@google.com2022-05-22T19:32:56ZLorenz Eberhardt<p>Title: Partition functions of the tensionless string</p>
<p>Abstract: I discuss string theory on AdS3xS3xT4 in the tensionless limit,with one unit of NS-NS flux. This theory is conjectured to be dual to the symmetric product orbifold CFT. I show how to compute the full string partition function on various locally AdS3 backgrounds, such as thermal AdS3, the BTZ black and conical defects,and find that it is independent of the actual background, but only depends on the boundary geometry. Consequently, reproducing the boundary partition function does not require a sum over bulk geometries,but rather agrees with the string partition function on any bulk geometry with the appropriate boundary. I argue that the same mechanism shows the factorization of the bulk partition function when geometries with disconnected boundaries are considered.</p>Asia/Jerusalem2020-09-15T11:30:00Asia/Jerusalem2020-09-15T12:30:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/lorenz-eberhardt/3adpt8bs4gi6lm00l1cipqq752@google.com2022-05-22T19:32:56ZIrene Valenzuela ( Harvard)<p>Title:</p>
<p>Merging Swampland Conjectures using strings and membranes</p>
<p>Abstract:<br />
In this talk I will discuss new relations that appear among the Swampland Conjectures when analysing the properties of low codimension BPS objects, in particular strings and membranes in N=1 4D EFTs. I will review the state of the art of the Swamplandprogram and revisit the most important conjectures, namely the Weak Gravity Conjecture (WGC) and the Swampland Distance Conjecture (SDC). Then I will describe how to apply the WGC to low codimension BPS objects by interpreting the 4d backreaction of these objectsas a classical RG flow of their couplings. Constraints on the UV charges and tensions get then translated to constraints on the axionic kinetic terms and scalar potential of the EFT, which uncovers new relations among the Swampland Conjectures. In particular,we show that the WGC for strings implies the SDC, by using that infinite distance limits can be realised as RG flow endpoints of fundamental axionic strings. Similarly, WGC-saturating membranes generate a scalar potential satisfying the de Sitter Conjecture.</p>Asia/Jerusalem2020-09-22T16:00:00Asia/Jerusalem2020-09-22T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/irene-valenzuela-harvard/3kisp14kifmo5di9bvh8em59kh@google.com2022-05-22T19:32:56ZIsmail Zahed<pre>Title:Reggeized scattering, entanglement and chaos using AdS/CFT</pre>
<pre>ABSTRACT:The eikonalized parton-parton scattering amplitude at large energy and </pre>
<pre>large impact parameter, is dominated by the exchange of a hyperbolic surface in </pre>
<pre>walled AdS. Its analytical continuation yields a worldsheet instanton that is </pre>
<pre>at the origin of the Reggeization of the amplitude and a thermal-like </pre>
<pre>quantum entropy. I will construct the entangled density matrix following from the</pre>
<pre> exchanged surface, and show that its von-Neumann entanglement entropy </pre>
<pre>coincides with its thermal-like entropy. The ratio of the entanglement entropy </pre>
<pre>to the transverse growth of the exchanged surface is similar to the Bekenstein </pre>
<pre>entropy ratio for a black-hole, with a natural definition of saturation </pre>
<pre>and the on-set of chaos in high energy collisions. The largest eigenvalues </pre>
<pre>of the entangled density matrix obey a cascade equation in rapidity, </pre>
<pre>reminiscent of non-linear QCD evolution of wee-dipoles </pre>
<pre>at low-x and weak coupling. We suggest that the largest eigenvalues </pre>
<pre>describe the probability distributions of wee-quanta at low-x </pre>
<pre>and strong coupling that maybe measurable at present and future hadron-hadron </pre>
<pre>and lepton- hadron colliders.</pre>Asia/Jerusalem2020-09-29T16:00:00Asia/Jerusalem2020-09-29T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/ismail-zahed/4nq1jjjk2i3p5qm94c8adn9ahh@google.com2022-05-22T19:32:56ZShota komatsu<p>Title: Landau diagrams in AdS and S-matrices from conformal correlators</p>
<p>Abstract: Quantum field theories in AdS generate conformalcorrelation functions on the boundary, and in the limit where AdS is nearly flat one should be able to extract an S-matrix from such correlators. We discuss a particularly simple position-space procedure to do so. It features a direct map from boundary positionsto (on-shell) momenta and thereby relates cross ratios to Mandelstam invariants. This recipe succeeds in several examples, includes the momentum-conserving delta functions, and can be shown to imply the two proposals based on Mellin space and on the OPE data.Interestingly the procedure does not always work: the Landau singularities of a Feynman diagram are shown to be part of larger regions, to be called `bad regions’, where the flat-space limit of the Witten diagram diverges. To capture these divergences we introducethe notion of Landau diagrams in AdS. As in flat space, these describe on-shell particles propagating over large distances in a complexified space, with a form of momentum conservation holding at each bulk vertex. As an application we recover the anomalousthreshold of the four-point triangle diagram at the boundary of a bad region.</p>Asia/Jerusalem2020-10-06T16:00:00Asia/Jerusalem2020-10-06T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/shota-komatsu/7dg17tuu7lqur4ffc8ihuvpi4i@google.com2022-05-22T19:32:56ZLorenzo di Pietro<p> Title: Boundary conditions for a free scalar field</p>
<p>Abstract: </p>
<p>In the first part of the talk, I will consider the problem of classifying the conformal boundary conditions (b.c.) for the free scalar CFT. We will see how to tackle this problem using conformal bootstrap techniques. In the case of 4d bulk, I will show ournumerical results, which feature a “kink” that indicates the existence of a non-trivial “interacting” b.c., besides the obvious Neumann and Dirichlet “free” b.c.’s.</p>
<p>In the second part of the talk, I will discuss the RG flow of a 4d free scalar field coupled to large N vector models on the boundary. The (classically marginal) coupling involves the boundary mode of the scalar and the O(N) single-trace scalar operator. Iwill explain that the resulting RG connects two fixed points with bulk and boundary decoupled, and the local 3d sector is the free vector model in one end, and the critical one in the other end. This same RG admits two weak-strong dual descriptions, one fromthe free end, and one from the critical end. </p>Asia/Jerusalem2020-10-13T11:30:00Asia/Jerusalem2020-10-13T12:30:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/lorenzo-di-pietro-2/3se4418jbdb5e3chkq5g0h4ob5@google.com2022-05-22T19:32:56ZRob Myers<div style=", Tahoma, Arial, sans-serif, serif, EmojiFont;font-size: 15px">Title: Quantum Extremal Islands Made Easy</p>
<p>Abstract: We illustrate the appearance of quantum extremal islands in holographic setups in higher dimensions. We emphasize the close parallel with the behaviour of holographic entanglement entropy in more familiar settings.</p>Asia/Jerusalem2020-10-20T16:00:00Asia/Jerusalem2020-10-20T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/rob-myers/4qlp7q9o9h4r8r9ufgqf6s6ngs@google.com2022-05-22T19:32:56ZPedro Vieira<p>Title : <span style="font-family: Tahoma, Geneva, sans-serif, serif, EmojiFont;font-size: 16px">Multi-point Bootstrap (and the search for a single open/closed string description of N=4 SYM)</span><br /><span style="font-family: Tahoma, Geneva, sans-serif, serif, EmojiFont;font-size: 16px"><br /></span></p>Asia/Jerusalem2020-10-27T16:00:00Asia/Jerusalem2020-10-27T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/pedro-vieira/5p3dt4dukfl17kcr4aukfda788@google.com2022-05-22T19:32:56ZBarak Kol<div style=", Tahoma, Arial, sans-serif, serif, EmojiFont;font-size: 15px">Title: Flux-based statistical prediction of three-body outcomes</p>
<div style=", Tahoma, Arial, sans-serif, serif, EmojiFont;font-size: 15px">
<div style=", Tahoma, Arial, sans-serif, serif, EmojiFont;font-size: 15px">Abstract: The three-body problem in Newtonian gravity is one of the oldest and richest problems in physics. Giants worked on it and it served as the source of numerous fields in theoretical physics and mathematics including perturbation theory, topology and chaos. Yet, it remains unsolved, and up to this work, the associated statistical theory was incomplete and flawed. </p>
<div style=", Tahoma, Arial, sans-serif, serif, EmojiFont;font-size: 15px">Here, I present a reduction of the differential decay rate in a factorized form. One factor is the flux of phase-space volume, rather than the volume itself which was used in all previous works, and it is given in a cutoff-independent closed-form. The other factor is related to the chaotic absorptivity and to Kirchhoff’s law of thermal radiation, also known as greybody radiation. Numerical evidence will be presented. I believe that this exact factorization cracks the problem and would allow future progress. Based on <a href="https://arxiv.org/abs/2002.11496" target="_blank" rel="noopener noreferrer">https://arxiv.org/abs/2002.11496</a></p>Asia/Jerusalem2020-11-03T16:00:00Asia/Jerusalem2020-11-03T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/barak-kol-2/6nvnhudfgkgeld3o7m5mu5uc0q@google.com2022-05-22T19:32:56ZNikolay Bobev<p style="margin-top: 0px;margin-bottom: 0px;, Tahoma, Arial, sans-serif, serif, EmojiFont;font-size: 15px">Title: The Unreasonable Effectiveness of Higher-Derivative Supergravity in AdS_4 Holography</p>
<p style="margin-top: 0px;margin-bottom: 0px;, Tahoma, Arial, sans-serif, serif, EmojiFont;font-size: 15px"></p>
<p style="margin-top: 0px;margin-bottom: 0px;, Tahoma, Arial, sans-serif, serif, EmojiFont;font-size: 15px">Abstract: I will describe the four-derivative corrections to four-dimensional N=2 minimal gauged supergravity and show that they are controlled by two constants. Interestingly, the solutions of the equations of motion in the two-derivative theory are not modified by the higher-derivative corrections. I will use this to arrive at a general formula for the regularized on-shell action for any asymptotically locally AdS_4 solution of the theory and show how the higher-derivative corrections affect black hole thermodynamic quantities in a universal way. I will employ these results in the context of holography to derive new explicit results for the subleading corrections in the large N expansion of supersymmetric partition functions on various compact manifolds for a large class of three-dimensional SCFTs arising from M2- and M5-branes. I will also briefly discuss possible extensions and generalizations of these results.</p>Asia/Jerusalem2020-11-10T16:00:00Asia/Jerusalem2020-11-10T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/nikolay-bobev/5qp9opsepki5kmkdul47badse3@google.com2022-05-22T19:32:56ZMark Mezei<p><span style="font-family: Calibri, Helvetica, sans-serif, serif, EmojiFont;font-size: 16px">Title: Fine probes of quantum chaos</span><br style="font-family: Calibri, Helvetica, sans-serif, serif, EmojiFont;font-size: 16px"><br style="font-family: Calibri, Helvetica, sans-serif, serif, EmojiFont;font-size: 16px"><span style="font-family: Calibri, Helvetica, sans-serif, serif, EmojiFont;font-size: 16px">Abstract: Quantum chaotic dynamics is associated to diverse physical phenomena and signatures. In this talk, we describe progress in building effective theories for three of these: the butterfly effect, the pole skipping phenomenon, and thermalization through the lens of entanglement entropy. We uncover their interplay by showing that the butterfly velocity plays an important role in all three manifestations of chaos. The discussion is informed by results from AdS/CFT and from models of SYK type.</span></p>Asia/Jerusalem2020-11-17T16:00:00Asia/Jerusalem2020-11-17T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/mark-mezei/7ot4id2eam1jl906b0nr4ikumg@google.com2022-05-22T19:32:56ZAlex Maloney<p>Title: Gravity from Averaging CFTs</p>
<p>Abstract: I will explore the idea that certain theories of gravity in Anti-de<br />
Sitter space are dual to an average over an ensemble of quantum<br />
theories, rather than to a specific quantum theory. I will describe<br />
an average over Narain’s family of two-dimensional conformal field<br />
theories which describe free bosons on a torus, and compute the<br />
partition function using the Siegel-Weil formula. The result takes<br />
the form of a sum over geometries as one would expect in a theory of<br />
gravity. But the gravitational theory looks more like a Chern-Simons<br />
theory than like Einstein gravity.</p>Asia/Jerusalem2020-11-24T16:00:00Asia/Jerusalem2020-11-24T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/alex-maloney/3co88s94vtqoadlucpmmc43irj@google.com2022-05-22T19:32:56ZDaniel Harlow<p><font size="3" color="black"><span style="font-size:12pt" id="divtagdefaultwrapper"><font color="black"><br />Title: Global symmetry, Euclidean gravity, and the black hole information problem</p>
<p>Abstract: <font size="2" color="black"><span style="font-size:13.6px">In this talk I will show how the essential ingredients of recent calculations of the Page curve of an evaporating black hole can be usedto generalize a recent argument against global symmetries beyond the AdS/CFT correspondence to more realistic theories of quantum gravity, illustrating a close connection between the absence of global symmetries and a unitary resolution of the black hole informationproblem. I’ll also give several low-dimensional examples of quantum gravity theories which do not have a unitary resolution of the black hole information problem, and which therefore can and do have global symmetries. Motivated by this discussion, I’ll conjecturethat in a certain sense Euclidean quantum gravity is equivalent to holography. Based on recent work with Edgar Shaghoulian.</span></font></font></span></font></p>Asia/Jerusalem2020-12-01T16:00:00Asia/Jerusalem2020-12-01T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/daniel-harlow/0oaogqg6bigrghidoo7djtrofv@google.com2022-05-22T19:32:56ZMatthew Heydeman<div style=", Tahoma, Arial, sans-serif, serif, EmojiFont;font-size: 15px">Title: The Statistical Mechanics of Near-BPS Black Holes</p>
<div style=", Tahoma, Arial, sans-serif, serif, EmojiFont;font-size: 15px">
<div style=", Tahoma, Arial, sans-serif, serif, EmojiFont;font-size: 15px">Abstract: The status of near extremal black holes in gravity and string theory has long remained unclear due to the failure of black hole thermodynamics at low temperatures. Such black holes have an AdS2 region, and substantial progress in the last few years has been made on Jackiw-Teitelboim (JT) dilaton gravity, which is an effective theory of nearly AdS2 spacetimes dual to a 1D “Schwarzian” theory. </p>
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<p>In this talk, we will derive and solve an effective theory to describe 4D flat space black holes which are just above the BPS bound. This theory is an N=4 supersymmetric version of the 2D Jackiw-Teitelboim gravity <-> 1D Schwarzian correspondence which we will obtain from nearly AdS2xS2 black holes in 4D N=2 supergravity. Using the Schwarzian description of these low temperature black holes, we can compute the partition function and density of states exactly. Our results verify several conjectures about near-BPS black holes coming from string theory, including an exact extremal degeneracy agreeing with Bekenstein-Hawking and a thermodynamic mass gap between extremal and near-extremal black holes.</p>
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<div style=", Tahoma, Arial, sans-serif, serif, EmojiFont;font-size: 15px">Based on a recent paper (<a href="https://arxiv.org/abs/2011.01953" target="_blank" rel="noopener noreferrer">https://arxiv.org/abs/2011.01953</a>) with MTH, Luca Iliesiu, Gustavo Turiaci, and Wenli Zhao. </p>Asia/Jerusalem2020-12-08T16:00:00Asia/Jerusalem2020-12-08T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/tba/6eb4m4cq41v726en27m1iq0f49@google.com2022-05-22T19:32:56ZHanukah – no seminarAsia/Jerusalem2020-12-15T16:00:00Asia/Jerusalem2020-12-15T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/hanukah-no-seminar/58avs1pm4kc6rgcoquvkrtbqjr@google.com2022-05-22T19:32:56ZShahar Hadar<div style=", Tahoma, Arial, sans-serif, serif, EmojiFont;font-size: 15px"><span style="font-family: arial, sans-serif, serif, EmojiFont">Title: </span><span style="font-family: arial, sans-serif, serif, EmojiFont">Photon Ring Autocorrelations</span></p>
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<div style=", Tahoma, Arial, sans-serif, serif, EmojiFont;font-size: 15px"><span style="font-family: arial, sans-serif, serif, EmojiFont">Abstract</span><span style="font-family: arial, sans-serif, serif, EmojiFont">: In the presence of a black hole, light sources connect to observers along multiple paths. As a result, observed brightness fluctuations must be correlated across different times and positions in black hole images. Photons that execute multiple orbits around the black hole appear near a critical curve in the observer sky, giving rise to the photon ring. In the talk I will describe the structure of a Kerr black hole’s photon ring. I will then discuss a novel observable we have recently proposed: the two-point correlation function of intensity fluctuations on the ring. I will describe its analytic computation within a toy model of stochastic emission, and show that it</span><span style="font-family: arial, sans-serif, serif, EmojiFont"> exhibits a universal, self-similar pattern consisting of multiple peaks of identical shape: while the profile of each peak encodes statistical properties of fluctuations in the source, the locations and heights of the peaks are determined purely by the black hole parameters. Measuring these peaks would demonstrate the existence of the photon ring without resolving its thickness, and would provide estimates of black hole mass and spin. I will discuss some prospective extensions and generalizations, and argue that w</span><span style="font-family: arial, sans-serif, serif, EmojiFont">ith regular monitoring over sufficiently long timescales, this measurement could be possible via interferometric imaging with modest improvements to the Event Horizon Telescope.</span></p>Asia/Jerusalem2020-12-22T16:00:00Asia/Jerusalem2020-12-22T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/shahar-hadar/01ofv8ulgsjmkvp95b6v5uf0p9@google.com2022-05-22T19:32:56ZSoumyadeep Chaudhuri<p><span style=", Tahoma, Arial, sans-serif, serif, EmojiFont;font-size: 15px">Title: Thermal order in large N conformal gauge theories</span><br style=", Tahoma, Arial, sans-serif, serif, EmojiFont;font-size: 15px"><br style=", Tahoma, Arial, sans-serif, serif, EmojiFont;font-size: 15px"><span style=", Tahoma, Arial, sans-serif, serif, EmojiFont;font-size: 15px">Abstract: Our experience with many physical systems tells us that usually when a symmetry is spontaneously broken at low temperatures, it is restored upon increasing the temperature sufficiently. The abundance of such systems raises the question of whether this is a universal feature of all quantum systems. In this talk, I will present examples of (3+1)-dimensional non-supersymmetric large N gauge theories which demonstrate violations of the above feature. I will argue that in the N tending to infinity limit, these theories have conformal manifolds which survive under all loop corrections to the beta functions of the couplings. I will show that under certain conditions, a subset of points on such a conformal manifold demonstrates the spontaneous breaking of a global symmetry at all nonzero temperatures. Furthermore, I will demonstrate that this symmetry breaking is accompanied by the Higgsing of a subset of gauge bosons leading the system to be in a persistent Brout-Englert-Higgs phase.</span></p>Asia/Jerusalem2020-12-29T16:00:00Asia/Jerusalem2020-12-29T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/soumyadeep-chaudhuri/2qk6uj03ncc8oesphcr9dvj2cn@google.com2022-05-22T19:32:56ZAnatoly Dymarsky<p><span style=", Tahoma, Arial, sans-serif;font-size: 13.3333px">Title: Comments on holographic description of </span><span style=", Tahoma, Arial, sans-serif;font-size: 13.3333px">Narain theories.</span><br style=", Tahoma, Arial, sans-serif;font-size: 13.3333px"><br style=", Tahoma, Arial, sans-serif;font-size: 13.3333px"><span style=", Tahoma, Arial, sans-serif;font-size: 13.3333px">Abstract: I will discuss to what extent holographic description of</span><br style=", Tahoma, Arial, sans-serif;font-size: 13.3333px"><span style=", Tahoma, Arial, sans-serif;font-size: 13.3333px">Narain theories can mimic the conventional picture of large c</span><br style=", Tahoma, Arial, sans-serif;font-size: 13.3333px"><span style=", Tahoma, Arial, sans-serif;font-size: 13.3333px">holography with weakly coupled gravity in the bulk. Namely is it</span><br style=", Tahoma, Arial, sans-serif;font-size: 13.3333px"><span style=", Tahoma, Arial, sans-serif;font-size: 13.3333px">possible that the effective IR bulk theory consist of “$U(1)$</span><br style=", Tahoma, Arial, sans-serif;font-size: 13.3333px"><span style=", Tahoma, Arial, sans-serif;font-size: 13.3333px">gravity” amended with some additional states. This picture leads to a</span><br style=", Tahoma, Arial, sans-serif;font-size: 13.3333px"><span style=", Tahoma, Arial, sans-serif;font-size: 13.3333px">hypothesis that in the large central charge limit density of states of</span><br style=", Tahoma, Arial, sans-serif;font-size: 13.3333px"><span style=", Tahoma, Arial, sans-serif;font-size: 13.3333px">any Narain theory would be bounded by below by that one of “$U(1)$</span><br style=", Tahoma, Arial, sans-serif;font-size: 13.3333px"><span style=", Tahoma, Arial, sans-serif;font-size: 13.3333px">gravity.” This immediately implies maximal value of spectral gap of</span><br style=", Tahoma, Arial, sans-serif;font-size: 13.3333px"><span style=", Tahoma, Arial, sans-serif;font-size: 13.3333px">primary fields is $Delta_1=c/(2pi e)$. In the rest of the talk I</span><br style=", Tahoma, Arial, sans-serif;font-size: 13.3333px"><span style=", Tahoma, Arial, sans-serif;font-size: 13.3333px">will discuss self-consistency of this picture using quantum code and</span><br style=", Tahoma, Arial, sans-serif;font-size: 13.3333px"><span style=", Tahoma, Arial, sans-serif;font-size: 13.3333px">chiral CFTs. First, I will show the proposed picture yields a new</span><br style=", Tahoma, Arial, sans-serif;font-size: 13.3333px"><span style=", Tahoma, Arial, sans-serif;font-size: 13.3333px">bound on quantum stabilizer codes, which is compatible with previously</span><br style=", Tahoma, Arial, sans-serif;font-size: 13.3333px"><span style=", Tahoma, Arial, sans-serif;font-size: 13.3333px">known bounds in the literature. Next, I will discuss variance of the</span><br style=", Tahoma, Arial, sans-serif;font-size: 13.3333px"><span style=", Tahoma, Arial, sans-serif;font-size: 13.3333px">density of states, which for consistency, must be vanishingly small in</span><br style=", Tahoma, Arial, sans-serif;font-size: 13.3333px"><span style=", Tahoma, Arial, sans-serif;font-size: 13.3333px">the large $c$ limit. I will consider ensembles of code and chiral</span><br style=", Tahoma, Arial, sans-serif;font-size: 13.3333px"><span style="color: rgb(33, 33, 33); font-family: wf_segoe-ui_normal, "Segoe UI", "Segoe WP", Tahoma, Arial, sans-serif; font-size: 13.3333px; background-</p>Asia/Jerusalem2021-01-05T16:00:00Asia/Jerusalem2021-01-05T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/anatoly-dymarsky-2/1fh61lkvve0kuvd0e9lqg45c72@google.com2022-05-22T19:32:56ZDavid Skinner<div class="" style=", Tahoma, Arial, sans-serif;font-size: 15px">Title: Twistors, Integrability and 4d Chern-Simons Theory</p>
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<div class="" style=", Tahoma, Arial, sans-serif;font-size: 15px">Abstract: It has long been known that many classical integrable systems can be obtained as symmetry reductions of the anti-self-dual Yang-Mills equations. Following a suggestion of Costello, I’ll show that actions for asd YM arise from holomorphic Chern-Simons theory on twistor space, defined with the help of a choice of meromorphic (3,0)-form. Applying the symmetry reduction in twistor space, one instead arrives at the description of the integrable system in terms of 4d Chern-Simons theory of Costello & Yamazaki.</p>Asia/Jerusalem2021-01-12T16:00:00Asia/Jerusalem2021-01-12T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/david-skinner/3ckfg9f9bu48o2d1r2g1vo7k3k@google.com2022-05-22T19:32:56ZNima Arkani-Hamed<p>Title: Frontiers in Positive Geometry.</p>
<p>Abstract: In this talk I will describe work in progress connecting scattering amplitudes to amplituhedra and positive geometries in kinematic space. For N=4 SYM in the planar limit, I will show how the geometry of the amplituhedron naturally provides a new approach to non-perturbative physics. I will also describe conjectural all-loop order, non-planar, non-supersymmetric amplituhedra for the tr(phi^3) theory–which are new (generally infinite) polytopes attached to any Riemann surface–and show how the connection to positive geometry forces the existence of “gravity” in this setting. </p>Asia/Jerusalem2021-01-19T16:00:00Asia/Jerusalem2021-01-19T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/nima-arkani-hamed/27v2ufeapa5gqrbp7dpprvt0o9@google.com2022-05-22T19:32:56ZSabrina Pasterski<p>Title: Using Soft Hair to Dissolve the Firewall</p>
<p>Abstract: We build on the observation by Hawking, Perry and Strominger that a global black hole space-time supports a large number of soft hair degrees of freedom to shed new light on the firewall argument by Almheiri, Marolf, Polchinski, and Sully. The soft hair carries a sizable amount of entropy and is encoded in a transition function that connects the asymptotic and near horizon regions. We argue that an infalling observer automatically measures the classical value of the soft mode before reachingthe horizon and that this measurement implements a code subspace projection that enables the reconstruction of interior operators. We use the soft hair dynamics to introduce an observer dependent notion of the firewall and show that an infalling observer neverencounters a firewall before reaching the singularity.</p>Asia/Jerusalem2021-01-26T16:00:00Asia/Jerusalem2021-01-26T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/sabrina-pasterski/08b1afn067f5dfgs628qhd7ipm@google.com2022-05-22T19:32:56ZNo seminars in February – semester breakAsia/Jerusalem2021-02-02T09:30:00Asia/Jerusalem2021-02-02T10:30:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/no-seminars-in-february-semester-break/371eeh569c8h4j0ftf9pi9nvg4@google.com2022-05-22T19:32:56ZKoenraad Schalm<p>Title: Detecting chaos in hydrodynamics </p>
<p>Abstract: Hydrodynamics assumes local equilibration and equilibration assumes ergodic mixing driven by chaos — at least in semi-classical systems. For a generic such system the timescales of macroscopic thermalization and onset of microscopic chaos are very different. Nevertheless, it is a pillar of Boltzmann transport that long-time equilibration can be computed from microscopic dynamics. We show how in these systems the two timescales are in fact related. Moreover, we show that a similar connection between both scales surprisingly also exists in extremely strongly coupled systems through a phenomenon christened pole-skipping in hydrodynamic response.</p>Asia/Jerusalem2021-03-02T16:00:00Asia/Jerusalem2021-03-02T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/koenraad-schalm/3udiq1p52gpo5opri53ogth979@google.com2022-05-22T19:32:56ZEric Perlmutter<p> Title: A CFT Distance Conjecture</p>
<p>Abs: We formulate conjectures relating the geometry of conformal manifolds to the spectrum of local operators in conformal field theories in d>2 spacetime dimensions. We focus on conformal manifolds with limiting points at infinite distance with respect tothe Zamolodchikov metric. Our central conjecture is that all theories at infinite distance possess an emergent higher-spin symmetry, generated by an infinite tower of currents whose anomalous dimensions vanish exponentially in the distance. Our conjecturesare related to the Distance Conjecture in the swampland program. We discuss the supporting evidence, their holographic interpretation, and implications for superconformal field theories. </p>Asia/Jerusalem2021-03-09T16:00:00Asia/Jerusalem2021-03-09T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/eric-perlmutter/1rm2m51f17ek51his6qa45a9p1@google.com2022-05-22T19:32:56ZZhenbin Yang<p>Title: Replica wormhole, Page curve, global symmetry and remnant</p>
<p>Abstract:<br />
A central dogma in the current theoretical study of black holes is that they can be viewed as an ordinary quantum system with large degrees of freedom. In the talk I will argue that replica wormhole gives strong evidence to the central dogma, including deriving the Page curve of the Hawking radiation, and an explicit construction of a complete basis of the black hole interior states. We will also comment on its relation with violation of global symmetry in quantum gravity.</p>Asia/Jerusalem2021-03-16T16:00:00Asia/Jerusalem2021-03-16T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/zhenbin-yang/12v6a3de181f6aan7d78d01ime@google.com2022-05-22T19:32:56ZJordan Cotler<p>Title: Black hole microstate statistics from Euclidean wormholes<br />
Abstract: Over the last several years, it has been shown that black hole microstate level statistics in various models of 2D gravity are encoded in wormhole amplitudes. These statistics quantitatively agree with predictions of random matrix theory for chaotic quantum systems; this behavior is realized since the 2D theories in question are dual to matrix models. But what about black hole microstate statistics for Einstein gravity in 3D and higher spacetime dimensions, and ultimately in non-perturbative string theory? We will discuss progress in these directions. In 3D, we compute a wormhole amplitude that encodes the energy level statistics of BTZ black holes. In 4D and higher, we find analogous wormholes which appear to encode the level statistics of small black holes just above threshold. Finally, we study analogous Euclidean wormholes in the low-energy limit of type IIB string theory; we provide evidence that they encode the level statistics of small black holes just above threshold in AdS5 x S5. Remarkably, these wormholes appear to be stable in appropriate regimes, and dominate over brane-anti-brane nucleation processes in the computation of black hole microstate statistics.</p>Asia/Jerusalem2021-04-06T16:00:00Asia/Jerusalem2021-04-06T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/avia-raviv-moshe/402qsamr4a7r7rr8359gvb1cb9@google.com2022-05-22T19:32:56ZYifan Wang – SPECIAL TIME<p>Title: Defects and Anomalies in Quantum Field Theories</p>
<p>Abstract: I will review some recent developments in understanding the structure of anomalies in the presence of defects in CFTs. The defect insertions lead to new ‘t Hooft anomalies and conformal anomalies on the defect worldvolume. The latter give riseto defect analogs of the c-theorem (a-theorem) which establish the monotonicity of defect RG flows. With supersymmetry, the defect conformal anomalies are related to the ‘t Hooft anomalies for certain U(1) R-symmetry in a simple way, and can be determinednon-perturbatively from an algebraic procedure. In the talk I’ll mostly focus on surface defects to be concrete and comment on extensions and future directions towards the end.</p>Asia/Jerusalem2021-04-20T16:30:00Asia/Jerusalem2021-04-20T17:30:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/yifan-wang/15ghgfdcj2tqjhcn82h95ll4vr@google.com2022-05-22T19:32:56ZChethan Krishnan<p>Title: Hints of Gravitational Ergodicity</p>
<p>Abstract: Recent developments on black holes have shown that a<br />
unitarity-compatible Page curve can be obtained from an<br />
ensemble-averaged semi-classical approximation. In this talk, we<br />
emphasize (1) that this peculiar manifestation of unitarity is not<br />
specific to black holes, and (2) that it can emerge from a single<br />
realization of an underlying unitary theory. To make things explicit,<br />
we consider a hard sphere gas leaking slowly from a small box into a<br />
bigger box. We reproduce the unitarity-compatible Page curve of this<br />
system, semi-classically. Berry’s ensemble in which the eigenstates<br />
live, plays a crucial role. The computation has structural parallels<br />
to replica wormholes, relies crucially on ensemble averaging at each<br />
epoch, and reveals the interplay between the multiple time-scales in<br />
the problem. Working with the ensemble averaged state rather than the<br />
entanglement entropy, we can also engineer an information “paradox”.<br />
Our system provides a concrete example in which the ensemble<br />
underlying the semi-classical Page curve is an ergodic proxy for a<br />
time average, and not an explicit average over many theories. The<br />
questions we address here are logically independent of the existence<br />
of horizons, so we expect that semi-classical gravity should also be<br />
viewed in a similar light.</p>Asia/Jerusalem2021-04-27T16:00:00Asia/Jerusalem2021-04-27T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/chethan-krishnan/1eo4fmlu7hdspvc0ev6o7tdnd0@google.com2022-05-22T19:32:56ZDaniel Jafferis – SPECIAL TIME<p>Title: Stringy ER=EPR.</p>
<p>Abstract: I will discuss a Lorentzian interpretation of the FZZ duality as an equivalence between string perturbation theory about a two sided black hole and an entangled combination of disconnected microstates. The microstates involve a condensate of folded strings extending from a strong coupling region. Part of the machinery involves string theory defined on Schwinger-Keldysh contours in target space, and a novel contour of integration of the string moduli associated to angular quantization. I will further present an AdS3 uplift of this duality.</p>Asia/Jerusalem2021-05-04T17:00:00Asia/Jerusalem2021-05-04T18:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/daniel-jafferis-special-time/284nf21193odds02j0ojilos1r@google.com2022-05-22T19:32:56ZAndrew Strominger<p>Progress in celestial holography</p>Asia/Jerusalem2021-05-11T16:00:00Asia/Jerusalem2021-05-11T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/andrew-strominger/6arhvlcbr0v5k945cv0l9apkcv@google.com2022-05-22T19:32:56ZVladimir Narovlansky<p>Title: Deviations from factorization in SYK</p>
<p>Abstract: Recently, there has been a revived interest in multi-boundary holographic systems and the contribution of Euclidean wormholes, in particular in Jackiw-Teitelboim (JT) gravity. We consider Sachdev-Ye-Kitaev (SYK) as a microscopic model for such holographic systems. While in JT gravity the non-factorizing contributions come from geometric wormholes, we get that in SYK there are much larger contributions. We give a diagrammatic description of all those leading contributions, analogous to Feynman diagrams. The holographic behavior is particularly interesting for fixed SYK couplings due to factorization, and we comment on that as well.</p>Asia/Jerusalem2021-05-18T16:00:00Asia/Jerusalem2021-05-18T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/vladimir-narovlansky/5n9ls6n5hr8om295r3sbrguqkj@google.com2022-05-22T19:32:56ZKantaro Ohmori<p>Title: 6d/5d dualities from Higgsing</p>
<p>Abstract: (Based on <a href="https://arxiv.org/abs/2103.02799">https://arxiv.org/abs/2103.02799</a> with a slightly different title.) <br />5d supersymmetric gauge theories are sometimes UV completed by 6d SCFTs. One such example is the duality between the affine quiver gauge theory in 5d and 6d so-called “conformal matter” theory labeled by a D or E type lie algebra. In this talk we will see that starting from this duality and performing nilpotent Higgsing on both sides, one can generate a huge set of 6d/5d dualities. The 6d side often involves a twist along a compactification by a discrete symmetry. The 5d side does not always admit a gauge theory description, but sometimes does and involves an exceptional gauge group including G or F type or an exceptional (non-fundamental) matter content. As a byproduct, we get a web-based formalism to compute the Nekrasov partition function for some of the exceptional 5d gauge theories.</p>Asia/Jerusalem2021-05-25T16:00:00Asia/Jerusalem2021-05-25T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/kantaro-ohmori/63g204lqs5ck6qptseoc9qqtuv@google.com2022-05-22T19:32:56ZAdar Sharon<p>Title: The Onset of Quantum Chaos</p>
<p>Abstract: We study the quantum version of the Lyapunov exponent in disordered theories. Generically the quantum Lyapunov exponent can only be computed in isolated CFTs, and so not much is known about the way in which chaos grows as we deform the theory away from weak coupling. In this talk we describe families of theories in which the disorder coupling is an exactly marginal deformation, allowing us to follow the Lyapunov exponent from weak to strong coupling. We find surprising behaviors in some cases, including a discontinuous transition into chaos, which we compare to the expectation from classical chaos. We also describe a new method allowing for computations in nontrivial CFTs deformed by disorder.</p>Asia/Jerusalem2021-06-01T16:00:00Asia/Jerusalem2021-06-01T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/adar-sharon/2jc4bljpi06olerct5t338l41b@google.com2022-05-22T19:32:56ZAvia Raviv-Moshe<p>Title: Large Charge Phases of CFTs</p>
<p>Abstract: CFTs with additional global symmetries often possess significant simplification in the regime in which the charges associated with the global symmetries become large. In this talk, we review some recent developments in the subject of CFTs atlarge global charges. We present results that are based on two papers: The first, (based on <a href="https://arxiv.org/abs/2102.12583">https://arxiv.org/abs/2102.12583</a>)involves the study of constraints due to spontaneously broken boosts and dilatation symmetries around heavy states, and the implications of the symmetry breaking for the spectrum of CFTs. In the second, we study boundary conformal field theories (BCFTs) witha global U(1) symmetry at the large charge regime. </p>Asia/Jerusalem2021-06-08T16:00:00Asia/Jerusalem2021-06-08T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/avia-raviv-moshe-2/1qg3b8c8cmuv9d782m6mhf30rf@google.com2022-05-22T19:32:56ZShira Chapman<p><b>Title: Complexity for CFTs in General Dimensions<br /></b><br />Abstract: In this talk, I will discuss circuit complexity for conformal field theory states in arbitrary dimensions. The circuits start from a primary state and move along a unitary representation of the Lorentzian conformal group. I will consider different choices of distance functions and explain how they can be understood in terms of the geometry of coadjoint orbits of the conformal group. This analysis will highlight a connection between the coadjoint orbits of the conformal group and timelike geodesics in anti-de Sitter spacetimes, with interesting implications regarding the holographic complexity proposals. This is based on a work with Nicolas Chagnet, Jan de Boer and Claire Zukowski.</p>Asia/Jerusalem2021-06-15T16:00:00Asia/Jerusalem2021-06-15T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/shira-chapman/12efk8v1gavh01a6g0uamiev8c@google.com2022-05-22T19:32:56ZOrr Sela<p>Title: Emergent symmetries in 3d and compactification from 5d</p>
<p>Abstract: We study the phenomenon of symmetry enhancement in quantum field theories in three dimensions, where the global symmetry of a model is larger in the IR than in the UV. We focus on supersymmetric theories where the situation is more tractable,and find an organizing principle for such enhancements in the form of compactifications of 5d theories on Riemann surfaces with flux in their global symmetries. We illustrate this by considering the compactification of the so-called 5d Seiberg SCFTs on tori,and obtain 3d theories with enhanced IR symmetries given by the 5d symmetry preserved by the chosen flux.</p>Asia/Jerusalem2021-07-06T16:00:00Asia/Jerusalem2021-07-06T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/orr-sela-2/3ofpqh45bgr1ck28fotukfs9tn@google.com2022-05-22T19:32:56ZGuilherme L. Pimentel<p>Title: The structure of the initial conditions of the universe<br />
Abstract: I will review what we know about the initial conditions of the universe from observations. Then, I will explain how they arise within the framework of inflation, and describe recent progress in classifying (or “bootstrapping”) the possible correlation functions between primordial fluctuations. Finally, time permitting, I will touch upon work in progress trying to apply the bootstrap philosophy to more general cosmologies.</p>Asia/Jerusalem2021-10-26T16:00:00Asia/Jerusalem2021-10-26T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/guilherme-l-pimentel/6f6jdpqcccuv4d9117vdr5uoul@google.com2022-05-22T19:32:56ZRoberto Emparan<p>Title: Holography of Chronology Protection<br />
Abstract: After an introduction to time-machine spacetimes and simple models of them, I will discuss recent work with M. Tomasevic where we use holography to study quantum effects when closed timelike curves (CTCs) are developed. We address the question of whether it is possible to send a signal across the chronology horizon, passing into the region where CTCs are present. We find that the self-interaction of quantum fields manages to banish the passage of field excitations into the non-chronal region. Going further, we compute the gravitational backreaction of the quantum fields, and show that the null chronology horizon turns into a strong, spacelike curvature singularity. This is one of the few controlled, explicit examples where we can see quantum effects change a Cauchy horizon into a spacelike singularity.</p>Asia/Jerusalem2021-11-09T16:00:00Asia/Jerusalem2021-11-09T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/roberto-emparan/42vfairg4is2jild3oquh9qi1v@google.com2022-05-22T19:32:56ZMiguel Paulos<p>Title: Mastering bounds on correlators<br />
Abstract: We discuss a new viewpoint onto the CFT landscape: bounds on values of CFT correlators. We show that such bounds can be obtained by constructing suitable ‘master functionals’. We present both numerical results for 3d CFTs as well as exact results for correlators on the line. The latter follow from crossing symmetric dispersion relations. We briefly discuss how these may be used to study the Regge and flat space limits of CFT correlators.</p>Asia/Jerusalem2021-11-16T16:00:00Asia/Jerusalem2021-11-16T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/miguel-paulos/5gh1sh5v7fs87ll6s3npk49mtr@google.com2022-05-22T19:32:56ZMicha Berkooz<p><b>Title: </b>Multi-trace correlators in the SYK model and Non-geometric wormholes</p>
<p><b>Abstract: </b>We consider the global fluctuations in the density of states of the SYK model, which are much larger than the standard RMT correlations. We provide a diagrammatic description of their leading and subleading behavior. In either case, the new set of correlations are not associated with (and are much larger than) the ones given by topological wormholes, and hint towards the dual of a single realization. In particular, we suggest that incorporating them in the gravity description requires the introduction of new, lighter and lighter, fields in the bulk with fluctuating boundary couplings.</p>Asia/Jerusalem2021-12-07T16:00:00Asia/Jerusalem2021-12-07T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/micha-berkooz/73gsvb2rgrlfaeg2tm1mm2tfgt@google.com2022-05-22T19:32:56ZShai Chester<p><i><b>Title:</b> </i>Bootstrapping <i>N</i> = 4 super-Yang-Mills on the conformal manifold</p>
<p><b><i>Abstract: </i></b>We study the <i>N </i>= 4 SYM stress tensor multiplet 4-point function for any value of the complexified coupling tau, and in principle any gauge group (we focus on SU(2) and SU(3) for simplicity). By combining non-perturbative constraints from the numerical bootstrap with two exact constraints from supersymmetric localization, we are able to compute upper bounds on low-lying CFT data (e.g. the Konishi) for any value of tau. These upper bounds are very close to the 4-loop weak coupling predictions in the appropriate regime. We also give preliminary evidence that these upper bounds become small islands under reasonable assumptions, in which case our method would provide a numerical solution to <i>N </i>= 4 SYM for any gauge group and tau.</p>Asia/Jerusalem2021-12-14T10:30:00Asia/Jerusalem2021-12-14T11:30:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/shai-chester-2/37igacc500r1snh9l0h8kds3eo@google.com2022-05-22T19:32:56ZRitam Sinha<p><b>Title: </b>Thermal Order in 3d</p>
<p><b>Abstract: </b>Our intuitive understanding of thermodynamics suggests that broken global symmetries in the stable vacuum of a physical system, get restored at high temperatures. We construct a unitary, UV-complete 3d QFT that instead exhibits a spontaneous breaking of continuous symmetries at all temperatures. Our model consists of two copies of the long-range vector model, with O(m) and O(N−m) global symmetry groups, perturbed by double-trace deformations. The model exhibits a conformal manifold in the large rank limit, that is lifted by 1/N corrections. A certain class of IR fixed points are shown to undergo SSB at finite temperature, with the pattern persisting to all temperatures due to scale-invariance. We provide evidence that the models in question are unitary, UV-complete, as well as invariant under conformal symmetry. Our work adds to the growing list of models that display persistent symmetry breaking (PSB), and discusses the necessary conditions for the models to display such a behaviour.</p>Asia/Jerusalem2021-12-14T12:00:00Asia/Jerusalem2021-12-14T13:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/ritam-sinha/4keuie44dlurm5mr6hunnk1qup@google.com2022-05-22T19:32:56ZGregory Tarnopolsky<p><b>Title: </b>Conformal operators in SYK-like models and their numerical effects</p>
<p><b>Abstract: </b>Quantum mechanical models with random interactions have an infinite number of bilinear operators, the scaling dimensions of which can be computed explicitly in the large N limit. The lowest dimension operators play an important role in thermodynamical properties of these models and define the behavior of various correlation functions in the infrared limit. In this talk I’ll show that some SYK-like models have operators with unusual anomalous dimensions. I also demonstrate how they can be observed in numerical computations.</p>
<p>Based on works with Maria Tikhanovskaya, Haoyu Guo and Subir Sachdev</p>
<p><a href="https://arxiv.org/abs/2010.09742">https://arxiv.org/abs/2010.09742</a><br /><a href="https://arxiv.org/abs/2012.14449">https://arxiv.org/abs/2012.14449</a></p>Asia/Jerusalem2021-12-21T16:00:00Asia/Jerusalem2021-12-21T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/gregory-tarnopolsky/1vbmf67epgo4vko9kbjgb2jln3@google.com2022-05-22T19:32:56ZAmihay Hanany<p><b>Title:</b> Magnetic Quivers, Phase Diagrams, and Physics at Strongly Coupled Quantum Field Theories</p>
<p><b>Abstract:</b> Quiver gauge theories experienced a breakthrough in activity through two important concepts, called “magnetic quivers” and “Hasse (phase) diagrams”. The first helps understanding the physics of strongly coupled gauge theories and exotic theories with tensionless strings in 6d or with massless gauge instants in 5d. The second gives an invaluable information about the phase structure of gauge theories, in analogy with phases of water. The talk will review these developments and explain their significance.</p>Asia/Jerusalem2021-12-28T10:30:00Asia/Jerusalem2021-12-28T11:30:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/amihay-hanany/19o54hhpq3v3qvs18t8qu1dsfl@google.com2022-05-22T19:32:56ZZohar Komargodski<p><b><i>Title: </i></b>Some aspects of line defects in d dimensions</p>
<p><b><i>Abstract:</i></b> We consider renormalization group flows on line defects in d dimensions. We define a “defect entropy” and argue that it decreases monotonically during RG flows. We apply this result to line defects which appear in condensed matter and high energy physics, including magnetic (SPT) defects, localized field defects, and Wilson loops. In some of these cases we make some new experimental predictions and in the case of Wilson lines we make some comparisons with localization and holography. </p>Asia/Jerusalem2022-01-04T10:30:00Asia/Jerusalem2022-01-04T11:30:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/zohar-komargodski-4/6lrd9j4921jdgdg2jhng0e591i@google.com2022-05-22T19:32:56ZDalimil Mazac<p><b>Title: </b>Automorphic Spectra and the Conformal Bootstrap</p>
<p><b>Abstract: </b>I will explain that the spectral geometry of hyperbolic manifolds provides a remarkably faithful model of the modern conformal bootstrap. In particular, to each hyperbolic manifold, one can associate a Hilbert space of local operators, which is a unitary representation of a conformal group. The scaling dimensions of the operators are related to the eigenvalues of the Laplacian on the manifold. The operators satisfy an operator product expansion. Finally, one can define their correlation functions and derive bootstrap equations constraining the spectrum. As an application, I will use conformal bootstrap techniques to derive upper bounds on the lowest positive eigenvalue of the Laplacian on closed hyperbolic surfaces and 2-orbifolds. 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 <a href="https://arxiv.org/abs/2111.12716">https://arxiv.org/abs/2111.12716</a>, which is joint work with P. Kravchuk and S. Pal.</p>Asia/Jerusalem2022-01-18T16:00:00Asia/Jerusalem2022-01-18T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/dalimil-mazac/3kuq9b42nicikfh28e1sh7v1gj@google.com2022-05-22T19:32:56ZJustin Kaidi<p><b>Title: </b>Kramers-Wannier-like duality defects in (3+1)d gauge theories</p>
<p><b>Abstract:</b> I will introduce a class of non-invertible topological defects in (3+1)d gauge theories whose fusion rules are the higher-dimensional analogs of those of the Kramers-Wannier defect in the (1+1)d critical Ising model. As in the lower-dimensional case, the presence of such non-invertible defects implies self-duality under a particular gauging of the discrete (higher-form) symmetries. I will illustrate this by means of the example of SO(3) Yang-Mills (YM) at θ=π, as well as SU(2)N=4 SYM at τ=i.</p>Asia/Jerusalem2022-01-25T16:00:00Asia/Jerusalem2022-01-25T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/justin-kaidi/2li38cs54alfu0vjju7tq7q3mi@google.com2022-05-22T19:32:56ZIgor Klebanov<p><b>Title: </b>O(N), Sp(2M), and OSp(1|2M) Models</p>
<p><b>Abstract: </b>The upper critical dimension of the O(N) vector model is well-known to be 4. In dimension 4-epsilon it is described by the Wilson-Fisher IR fixed point of the O(N) invariant scalar field theory with a small positive quartic coupling. Above 4 dimensions, this theory is non-renormalizable, but in 4+epsilon dimensions it formally has a UV fixed point at small negative coupling. For sufficiently large N, its UV completion in 4<d<6 is the theory of N+1 scalar fields with O(N) invariant cubic interactions. It possesses a weakly coupled IR fixed point in dimension 6-epsilon where the scaling dimensions agree with the 1/N expansion. The scaling dimensions also have imaginary parts that are exponentially small in N; this suggests the existence of near-critical behavior in 5 dimensions. </p>
<p>Replacing N of the scalar fields by 2M anticommuting scalars, we find Sp(2M) invariant fixed points with imaginary coupling constants in dimension 6-epsilon. In the special case M=1 the symmetry is enhanced to OSp(1|2), and we argue that this theory describes the critical behavior of the zero-state Potts model, or equivalently the random spanning forests. We end by discussing the OSp(1|4) invariant fixed point of the field theory with quintic interactions. Its upper critical dimension is 10/3, and the 10/3-epsilon expansion provides estimates of new critical exponents in d=3. </p>Asia/Jerusalem2022-03-08T16:00:00Asia/Jerusalem2022-03-08T18:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/igor-klebanov/0np8c5h85b6n7n7sfsei7ciusa@google.com2022-05-22T19:32:56ZHoracio Casini, Instituto Balseiro, Bariloche<p><u></u><b>Title: </b>A new look at completeness and generalized symmetries<u></u><br /><u></u><br /><b>Abstract:</b> <u></u>We describe a proposal for completeness in QFT. It asserts that the physical observable algebras produced by local degrees of freedom are the maximal ones compatible with causality. We elaborate on equivalent statements to this idea such as the non-existence of generalized symmetries and the uniqueness of the net of algebras. For non-complete theories, we explain how the existence of generalized symmetries is unavoidable, and further, that they always come in dual pairs with precisely the same size”, measured by an algebraic index. Entropic order/disorder parameters can be defined that sense the dual pairs of generalized symmetries and satisfy a “certainty relation”. We briefly describe applications to understand the density of charged states and to holography.</p>Asia/Jerusalem2022-03-22T16:00:00Asia/Jerusalem2022-03-22T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/horacio-casini/2vqqg6jh6u9g27vh0i3qh0bu4u@google.com2022-05-22T19:32:56ZAnthony Ashmore, U Chicago and Sorbonne<p><b>Title: </b>Exactly Marginal Deformations and their Supergravity Duals<br /><b><br /></b><br /><b>Abstract: </b>We study the space of supersymmetric AdS5 solutions of type IIB supergravity corresponding to the conformal manifold of the dual N = 1 conformal field theories. We show that the background geometry naturally encodes a generalised holomorphic structure, dual to the superpotential of the field theory, with the existence of the full solution following from a continuity argument. In particular, we address the long-standing problem of finding the gravity dual of the generic N = 1 deformations of N = 4 super Yang-Mills: though we are not able to give it in a fully explicit form, we provide a proof-of-existence of the supergravity solution. Using this formalism, we derive a new result for the Hilbert series of the deformed field theories.</p>Asia/Jerusalem2022-03-29T16:00:00Asia/Jerusalem2022-03-29T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/anthony-ashmore-u-chicago-and-sorbonne/4gucj5um8kke25d4b07egikbhb@google.com2022-05-22T19:32:56ZRob Myers, Perimeter Institute<p><b>Title: </b>Complexity=Anything?<br /><b><br /></b><br /><b>Abstract: </b>Motivated by holographic complexity, we examine a new class of gravitational observables in asymptotically AdS space associated with codimension-one slices or with codimension-zero regions. We argue that any of these observables is an equally viable candidate as the extremal volume for a gravitational dual of complexity.</p>Asia/Jerusalem2022-04-26T16:00:00Asia/Jerusalem2022-04-26T18:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/rob-myers-perimeter-institute/5he1400qvu6cr5a3jq6amtmoit@google.com2022-05-22T19:32:56ZAustin Joyce, Chicago U.<p><span><u></u><b>Title: </b>Static Responses and Symmetries of Black Holes<br /><u></u><br /><b>Abstract: </b><u></u></span>I will discuss features of the static responses of black holes in General Relativity. In particular, I will describe how black hole static responses are defined in point particle effective theory and will explain how the vanishing of black hole Love numbers is a consequence of symmetries of the wave equation in black hole backgrounds.</p>Asia/Jerusalem2022-05-03T16:00:00Asia/Jerusalem2022-05-03T17:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/austin-joyce-chicago-u/21i5j9k3d44ju1q4qf0nk06n89@google.com2022-05-22T19:32:56ZAmit Sever, TAU<p><b>Title: </b>Line Operators in Chern-Simons-Matter Theories and Bosonization in Three Dimensions<br /><b><br /></b><br /><b>Abstract: </b>We study Chern-Simons theories at large N with either bosonic or fermionic matter in the fundamental representation. The most fundamental operators in these theories are mesonic line operators, the simplest example being Wilson lines ending on fundamentals. We classify the conformal line operators along an arbitrary smooth path as well as the spectrum of conformal dimensions and transverse spins of their boundary operators at finite ‘t Hooft coupling. These line operators are shown to satisfy first-order chiral evolution equations, in which a smooth variation of the path is given by a factorized product of two line operators. We argue that this equation together with the spectrum of boundary operators are sufficient to uniquely determine the expectation values of these operators. We demonstrate this by bootstrapping the two-point function of the displacement operator on a straight line. We show that the line operators in the theory of bosons and the theory of fermions satisfy the same evolution equation and have the same spectrum of boundary operators. </p>Asia/Jerusalem2022-05-17T10:30:00Asia/Jerusalem2022-05-17T11:30:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/amit-sever-tau/09mfcnh0dv6jkv944dbe3ns35g@google.com2022-05-22T19:32:56ZErez Urbach, WIS<p><b>Title: </b>String stars in anti de Sitter space<br /><b><br /></b><br /><b>Abstract: </b>We study the ‘string star’ saddle, also known as the Horowitz-Polchinski solution, in the middle of d+1 dimensional thermal AdS space (d>2). We show that there’s a regime of temperatures in which the saddle is very similar to the flat space solution found by Horowitz and Polchinski. This saddle is hypothetically connected at lower temperatures to the small AdS black hole saddle. We also study, numerically and analytically, how the solutions are changed due to the AdS geometry for higher temperatures. Specifically, we describe how the solution joins with the thermal gas phase, and find the leading correction to the Hagedorn temperature due to the AdS curvature. Finally, we study the thermodynamic instabilities of the solution and argue for a Gregory-Laflamme-like instability whenever extra dimensions are present at the AdS curvature scale.</p>Asia/Jerusalem2022-05-17T12:00:00Asia/Jerusalem2022-05-17T13:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/erez-urbach-wis/2oaeeatdgsonq81mjbln25d66t@google.com2022-05-22T19:32:56ZMikhail Ivanov, IAS<p><b>Title: </b>Love and Naturalness</p>
<p><b>Abstract: </b>It has been known for a decade that black holes are the most rigid objects in the universe: their tidal deformations (Love numbers) vanish identically in general relativity in four dimensions. This has represented a naturalness problem in the context of classical worldline effective field theory. In my talk I will present a new symmetry of general relativity (Love symmetry) that resolves this naturalness paradox. I will show that perturbations of rotating black holes enjoy an SL(2,R) symmetry in the suitable defined near zone approximation. This symmetry, while approximate in general, in fact yields exact results about static tidal deformations. This symmetry also implies that generic regular black hole perturbations form infinite-dimensional SL(2,R) representations, and in some special cases these are highest weight representations. It is the structure of these highest weight representations that forces the Love numbers to vanish. All other facts about Love numbers, including their puzzling behaviour for higher dimensional black holes, also acquire an elegant explanation in terms of SL(2,R) representation theory. </p>Asia/Jerusalem2022-05-31T16:00:00Asia/Jerusalem2022-05-31T18:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/mikhail-ivanov-ias/2vsjn8ct96mod20sptms4opffm@google.com2022-05-22T19:32:56ZCarlos Hoyos<p><b>Title: </b>TBA</p>
<p><b>Abstract: </b>TBA</p>Asia/Jerusalem2022-06-14T10:30:00Asia/Jerusalem2022-06-14T11:30:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/carlos-hoyos-2/0rpkfkrkhm9ld4ltbobiphe93j@google.com2022-05-22T19:32:56ZFerrando Gwenael, TAU<p><b>Title: </b>TBA</p>
<p><b>Abstract: </b>TBA</p>Asia/Jerusalem2022-06-14T12:00:00Asia/Jerusalem2022-06-14T13:00:00en-USNeve Shalom0https://phsites.technion.ac.il/strings/event/ferrando-gwenael-tau/