researchseminars.org

Alexey Koshelev (UBI)
2021-12-06 14:00 - 15:00 UTC | https://stable.researchseminars.org/talk/FHD3/1/
Title: Resolving Black Holes singularities in Analytic infinite derivative theories of gravity (https://stable.researchseminars.org/talk/FHD3/1/)
by Alexey Koshelev (UBI) as part of Frontiers of Holographic Duality-3

Abstract
In my talk I will show that Analytic infinite derivative gravity in any dimension represents the most general gravity action ever needed to extract propagator around maximally symmetric spacetimes. Moving on, I will show that such a theory is geodesically complete leading to the resolution of the Black Hole singularities. Thus singular blackholes (Schwarzschild as an example) can be understood as non-singular compact objects still with a horizon, whose core is governed by the mass and the effective scale of the non-locality.

Oleg Andreev (Munich University)
2021-12-07 14:00 - 15:00 | https://stable.researchseminars.org/talk/FHD3/2/
Title: From strings to QCD: The study of doubly heavy hadrons (https://stable.researchseminars.org/talk/FHD3/2/)
by Oleg Andreev (Munich University) as part of Frontiers of Holographic Duality-3

Abstract
We will discuss the string theory constructions for the $QQq$ and $QQ\bar q\bar q $systems. Following the hadro-quarkonium picture the potential is a function of separation between the heavy quarks. The results show the universality of the string tension and factorization at small separations expected from heavy quark-diquark symmetry. The potentials look very similar at small quark separations but at larger separations they differ. The reason for this is that the flattening of the potentials happens at two well-separated scales as follows from the two different mechanisms: string breaking by light quarks for QQq and string junction annihilation for $QQ\bar q\bar q$.

Anastasia Golubtsova (JINR)
2021-12-07 15:00 - 16:00 | https://stable.researchseminars.org/talk/FHD3/3/
by Anastasia Golubtsova (JINR) as part of Frontiers of Holographic Duality-3

Abstract: TBA

Matti Jarvinen (APCTP)
2021-12-08 13:00 - 14:00 | https://stable.researchseminars.org/talk/FHD3/4/
Title: Generalized 3D instanton crystals (https://stable.researchseminars.org/talk/FHD3/4/)
by Matti Jarvinen (APCTP) as part of Frontiers of Holographic Duality-3

Abstract
Nuclear matter at large number of colors is necessarily in a solid phase. In particular holographic nuclear matter takes the form of a crystal of instantons of the flavor group. I analyze the three-dimensional crystal structures and the orientation patterns for the two-body potential motivated by holographic duality. I use simulations of large ensembles of instantons to identify the lattice structure and orientations for various parameter values of the two-body potential. The resulting phase diagram is surprisingly complex, including a variety of ferromagnetic and antiferromagnetic crystals with various global orientation patterns, and various "non-Abelian" crystals where orientations have no preferred direction. The simulation results are augmented by analytic analysis of the long-distance divergences, and numerical computation of the (divergence free) energy differences between the non-Abelian crystals, which precisely determine the structure of the phase diagram.

Giuseppe Policastro (Ecole Normale)
2021-12-08 14:00 - 15:00 | https://stable.researchseminars.org/talk/FHD3/5/
Title: A semi-holographic model of non-Fermi liquids (https://stable.researchseminars.org/talk/FHD3/5/)
by Giuseppe Policastro (Ecole Normale) as part of Frontiers of Holographic Duality-3

Abstract
In recent years, the holographic correspondence has been used in many contexts
to explore properties of strongly coupled systems that are hard to explain
by conventional methods. One instance of such systems is given by the high-T superconductors,
which exhibit non-Fermi liquid behavior in the so-called "strange metal" phase above the critical temperature.
I will discuss the holographic constructions of these systems,
and in particular a model that I and my collaborators are currently investigating,
based on a semi-holographic approach. I will discuss the results for the transport properties, in particular
I will show that under certain conditions an emergent linear-in-T behavior
of the longitudinal resistivity appears over a significant range of temperatures.

Jonah Kudler-Flam (Chicago University)
2021-12-09 14:00 - 15:00 | https://stable.researchseminars.org/talk/FHD3/6/
Title: Distinguishability in Random States, Eigenstates, and Gravity (https://stable.researchseminars.org/talk/FHD3/6/)
by Jonah Kudler-Flam (Chicago University) as part of Frontiers of Holographic Duality-3

Abstract
Recently, there has been significant progress in solving the black hole information problem from explicit calculations of the entropy of Hawking radiation, confirming consistency of gravity with unitarity. One aspect of the information problem left unresolved by entropy calculations is the distinguishability of different black hole microstates: why do different microstates appear to lead to the same final (thermal) state? I will address this problem by studying the distinguishability of radiation coming from different black holes. In parallel, I will present a derivation of the subsystem eigenstate thermalization hypothesis for a class of chaotic many-body systems as well as generalizations to tensor network states.

Saso Grozdanov (University of Ljubljana)
2021-12-09 15:00 - 16:00 | https://stable.researchseminars.org/talk/FHD3/7/
by Saso Grozdanov (University of Ljubljana) as part of Frontiers of Holographic Duality-3

Abstract: TBA

Larus Thorlacius (University of Iceland)
2021-12-10 14:00 - 15:00 | https://stable.researchseminars.org/talk/FHD3/8/
Title: Moving black branes and Lifshitz hydrodynamics at generic z (https://stable.researchseminars.org/talk/FHD3/8/)
by Larus Thorlacius (University of Iceland) as part of Frontiers of Holographic Duality-3

Abstract
Quantum critical fluids with Lifshitz symmetry, or Lifshitz fluids for short, have interesting properties that set them aside from more conventional fluid systems. In particular, a Lifshitz fluid with a generic dynamical critical exponent z > 1 does not have boost symmetry meaning that a moving fluid is physically distinct from a fluid at rest in a moving coordinate frame. We show how a relatively simple Einstein-Maxwell-Dilaton model provides a concrete holographic realisation of Lifshitz fluids. In this setting, a black brane at generic z carrying linear momentum along the boundary corresponds to a non-equilibrium steady state of the fluid. We obtain the stress tensor complex for the dual field theory via a suitably defined holographic renormalisation procedure and demonstrate that the expected hydrodynamic relations for a Lifshitz perfect fluid are satisfied.

Michal Heller (Max Planck Institute for Gravitational Physics)
2021-12-13 15:00 - 16:00 | https://stable.researchseminars.org/talk/FHD3/9/
Title: Towards deriving a gravity dual to complexity (https://stable.researchseminars.org/talk/FHD3/9/)
by Michal Heller (Max Planck Institute for Gravitational Physics) as part of Frontiers of Holographic Duality-3

Abstract
What are boundary interpretations of holographic complexity proposals and what are gravity duals to complexity are important open questions. I will discuss two ongoing efforts to answer them, which are based on searching for a gravity dual of a circuit cost and, through minimization of the latter object, to a gravity dual of bona fide complexity. Based on 2101.01185 and an ongoing work.

Hong Liu (MIT)
2021-12-13 16:00 - 17:00 | https://stable.researchseminars.org/talk/FHD3/10/
Title: Causal connectability between quantum systems and the black hole interior in holographic duality (https://stable.researchseminars.org/talk/FHD3/10/)
by Hong Liu (MIT) as part of Frontiers of Holographic Duality-3

Abstract
In holographic duality an eternal AdS black hole is described by two copies of the boundary CFT in the thermal field double state. This identification still has many puzzles, including the boundary descriptions of the event horizons, the interiors of the black hole, and the singularities. Compounding these mysteries is the fact that, while there is no interaction between the CFTs, observers from them can fall into the black hole and interact. We will address these issues in this talk. In particular, we (i) present a boundary formulation of infalling observers; (ii) show that in any holographic systems, a sharp event horizon can only emerge in the infinite N limit; (iii) give an explicit construction in the boundary theory of an evolution operator for a family of bulk in-falling observers, making manifest the boundary emergence of the black hole horizons, the interiors, and the associated causal structure.

A by-product is a concept called causal connectability, which is a criterion for any two quantum systems (which do not necessarily have a known gravity dual) to have an emergent sharp horizon structure.

Hao Geng (Harvard U.)
2021-12-14 14:00 - 15:00 | https://stable.researchseminars.org/talk/FHD3/11/
Title: Entanglement Islands in Braneworlds (https://stable.researchseminars.org/talk/FHD3/11/)
by Hao Geng (Harvard U.) as part of Frontiers of Holographic Duality-3

Abstract
Entanglement island is a recently emergent concept playing an important role in resolving the black hole information paradox. In these resolution proposals the black hole is coupled to a bath which absorbs the radiation from the black hole and we can calculate the entanglement entropy of the black hole radiation as a function of time by studying the bath. The results are consistent with Page's argument that the entanglement entropy versus time diagram obeys unitarity-- a Page curve. In higher dimensions, this calculation of the Page curve can be done only in braneworld models. More precisely, the Karch-Randall braneworld models and for AdS black holes. A closer look at the braneworld models tells us that the graviton is massive as the massless graviton mode is not normalizable. However, this effect of having a massive graviton is induced by coupling the black hole to a bath which is a universal feature of all the resolution proposals in higher dimensions. Several attempts to construct entanglement islands for massless gravity using braneworld give us many interesting new setups to study quantum gravity-- including a codimension two holography in AdS (wedge holography) and Page curve for de Sitter radiation. Though these attempts didn't provide us with entanglement islands for massless gravity in asymptotically AdS spaces. We will see that a more careful study tells us that in a large set of situations entanglement islands don't exist in massless gravity theories. In the talk I will give a complete review of this line of research.

Gabor Sarosi (CERN)
2021-12-14 15:00 - 16:00 | https://stable.researchseminars.org/talk/FHD3/12/
Title: The volume of the black hole interior at late times (https://stable.researchseminars.org/talk/FHD3/12/)
by Gabor Sarosi (CERN) as part of Frontiers of Holographic Duality-3

Abstract
The volume of the interior of a two-sided eternal black hole classically grows forever. I will show that in JT gravity, summing the non-perturbative contribution of higher topologies leads to a saturation of the volume of the interior at times exponential in the entropy of the black hole. I will explain that this is evidence for the conjecture that the size of the interior is related to the complexity of the holographically dual quantum state.

Natalia Pinzani-Fokeeva (MIT)
2021-12-15 14:00 - 15:00 | https://stable.researchseminars.org/talk/FHD3/13/
Title: Enstrophy and black hole supertranslations (https://stable.researchseminars.org/talk/FHD3/13/)
by Natalia Pinzani-Fokeeva (MIT) as part of Frontiers of Holographic Duality-3

Abstract
Enstrophy is an approximately conserved quantity in 2+1 dimensional fluid flows that has dramatic consequences for the phenomenology of nonrelativistic turbulence: it implies an inverse energy cascade. In this talk, I will present an algorithm on how to construct an enstrophy current for generic fluid flows (relativistic and non). In addition, I will show how a subset of certain horizon symmetries of 3+1 dimensional AdS black holes also lead to enstrophy conservation in the dual holographic fluid theory.

Jorit Kruthoff (Stanford)
2021-12-15 17:00 - 18:00 | https://stable.researchseminars.org/talk/FHD3/14/
Title: Gravity factorized (https://stable.researchseminars.org/talk/FHD3/14/)
by Jorit Kruthoff (Stanford) as part of Frontiers of Holographic Duality-3

Abstract
In this talk I will discuss models of two-dimensional gravity that resolve the factorization puzzle and have a discrete spectrum, whilst retaining a semiclassical description. A novelty of these models is that they contain non-trivially correlated spacetime branes or, equivalently, nonlocal interactions in their action. Demanding factorization fixes almost all brane correlators, and the exact geometric expansion of the partition function collapses to only two terms: the black hole saddle and a subleading ``half-wormhole'' geometry, whose sum yields the desired discrete spectrum. Non-perturbatively, the correlated branes are a certain multitrace interaction and I will show how it results in a factorizing theory with discrete spectrum. I will end with a few comments on the relevance of wormholes, the matrix model implementation and higher dimensions.

Pawel Caputa (Warsaw University)
2021-12-16 14:00 - 15:00 | https://stable.researchseminars.org/talk/FHD3/15/
Title: Geometry of Krylov Complexity (https://stable.researchseminars.org/talk/FHD3/15/)
by Pawel Caputa (Warsaw University) as part of Frontiers of Holographic Duality-3

Abstract
I will describe geometric aspect of the operator growth
and Krylov complexity from a new perspective of symmetries and
coherent states. As the main examples I will talk about operator
growth and Krylov complexity in the SYK model and in 2d CFTs. Based
on arXiv: 2109.03824 [hep-th] and arXiv: 2110.10519 [hep-th].

Sergey Vernov (MSU)
2021-12-16 15:00 - 16:00 | https://stable.researchseminars.org/talk/FHD3/16/
Title: Nonlocal gravity and F(R) models (https://stable.researchseminars.org/talk/FHD3/16/)
by Sergey Vernov (MSU) as part of Frontiers of Holographic Duality-3

Abstract: TBA

Niko Jokela (University of Helsinki)
2021-12-17 14:00 - 15:00 | https://stable.researchseminars.org/talk/FHD3/17/
Title: NICER view on holographic QCD (https://stable.researchseminars.org/talk/FHD3/17/)
by Niko Jokela (University of Helsinki) as part of Frontiers of Holographic Duality-3

Abstract
Holographic techniques are particularly fit to analyzing matter at extreme conditions where QCD matter is strongly coupled. Combining predictions of the holographic model with state-of-the-art effective field theory models of nuclear matter, I construct a family of feasible "hybrid" equations of state which cover both the quark matter and nuclear matter phases. The model predicts, among other things, that the NICER's radius measurement is fully consistent with the absence of quark matter inside massive neutron stars. I also briefly overview some results that holography has achieved on general level as well as discuss how I foresee holography contributing to compact-star physics in the coming years

Kristina Rannu (PFUR)
2021-12-17 15:00 - 16:00 | https://stable.researchseminars.org/talk/FHD3/18/
Title: Anisotropic solutions for a holographic light-quark model with an external magnetic field (https://stable.researchseminars.org/talk/FHD3/18/)
by Kristina Rannu (PFUR) as part of Frontiers of Holographic Duality-3

Abstract: TBA
