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BEGIN:VEVENT
SUMMARY:Stefano Profumo (Santa Cruz Institute for Particle Physics and Uni
versity of California\, Santa Cruz\, California\, USA)
DTSTART;VALUE=DATE-TIME:20200507T140000Z
DTEND;VALUE=DATE-TIME:20200507T153000Z
DTSTAMP;VALUE=DATE-TIME:20230208T074105Z
UID:QASTM/1
DESCRIPTION:Title: Wh
at is the Dark Matter?\nby Stefano Profumo (Santa Cruz Institute for P
article Physics and University of California\, Santa Cruz\, California\, U
SA) as part of Quantum Aspects of Space-Time and Matter\n\n\nAbstract\nFou
r fifths of the matter in the universe is made of something completely dif
ferent from the "ordinary matter" we know and love. I will explain why thi
s "dark matter" is an unavoidable ingredient to explain the universe as we
observe it\, and I will describe what the fundamental\, particle nature o
f the dark matter could possibly be. I will then give an overview of strat
egies to search for dark matter as a particle\, describe a few examples of
possible hints of discovery\, and outline ways forward in this exciting h
unt.\n
LOCATION:https://researchseminars.org/talk/QASTM/1/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Subir Sachdev (Department Chair\, Herchel Smith Professor of Physi
cs\, Department of Physics\, Harvard University\, Boston\, USA)
DTSTART;VALUE=DATE-TIME:20200514T150000Z
DTEND;VALUE=DATE-TIME:20200514T170000Z
DTSTAMP;VALUE=DATE-TIME:20230208T074105Z
UID:QASTM/2
DESCRIPTION:Title: Li
near in temperature resistivity in the limit of zero temperature from the
time reparameterization soft mode\nby Subir Sachdev (Department Chair\
, Herchel Smith Professor of Physics\, Department of Physics\, Harvard Uni
versity\, Boston\, USA) as part of Quantum Aspects of Space-Time and Matte
r\n\nLecture held in QASTM seminar series talk.\n\nAbstract\nThe most puzz
ling aspect of the `strange metal' behavior of correlated electron compoun
ds is that the linear in temperature resistivity often extends down to low
temperatures\, lower than natural microscopic energy scales. We consider
recently proposed deconfined critical points (or phases) in models of elec
trons in large dimension lattices with random nearest-neighbor exchange in
teractions. The criticality is in the class of Sachdev-Ye-Kitaev models\,
and exhibits a time reparameterization soft mode representing gravity in d
ual holographic theories. We compute the low-temperature resistivity in a
large M limit of models with SU(M) spin symmetry\, and find that the domin
ant temperature dependence arises from this soft mode. The resistivity is
linear in temperature down to zero temperature at the critical point\, wit
h a co-efficient universally proportional to the product of the residual r
esistivity and the co-efficient of the linear in temperature specific heat
. We argue that the time reparameterization soft mode offers a promising a
nd generic mechanism for resolving the strange metal puzzle.\n
LOCATION:https://researchseminars.org/talk/QASTM/2/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Zohar Komargodski (Simons Center for Geometry and Physics\, Stony
Brook University (SUNY Stony Brook)\, New York\, USA)
DTSTART;VALUE=DATE-TIME:20200518T160000Z
DTEND;VALUE=DATE-TIME:20200518T173000Z
DTSTAMP;VALUE=DATE-TIME:20230208T074105Z
UID:QASTM/3
DESCRIPTION:Title: Th
ermal order in conformal theories\nby Zohar Komargodski (Simons Center
for Geometry and Physics\, Stony Brook University (SUNY Stony Brook)\, Ne
w York\, USA) as part of Quantum Aspects of Space-Time and Matter\n\n\nAbs
tract\nIt is widely expected that at sufficiently high temperatures order
is always lost\, e.g. magnets loose their ferromagnetic properties. We pos
e the question of whether this is always the case in the context of quantu
m field theory in d space dimensions. More concretely\, one can ask whethe
r there exist critical points (CFTs) which break some global symmetry at a
rbitrary finite temperature. The most familiar CFTs do not exhibit symmetr
y breaking at finite temperature\, and moreover\, in the context of the Ad
S/CFT correspondence\, critical points at finite temperature are described
by an uncharged black brane which obeys a no-hair theorem. Yet\, we show
that there exist CFTs which have some of their internal symmetries broken
at arbitrary finite temperature. Our main example is a vector model which
we study both in the epsilon expansion and arbitrary rank as well as the l
arge rank limit (and arbitrary dimension). The large rank limit of the vec
tor model displays a conformal manifold\, a moduli space of vacua\, and a
deformed moduli space of vacua at finite temperature. The appropriate Namb
u-Goldstone bosons including the dilaton-like particle are identified. Usi
ng these tools we establish symmetry breaking at finite temperature for fi
nite small ϵ. We also prove that a large class of other fixed points\, wh
ich describe some of the most common quantum magnets\, indeed behave as ex
pected and do not break any global symmetry at finite temperature. We disc
uss some of the consequences of finite temperature symmetry breaking for t
he spectrum of local operators. Finally\, we propose a class of fixed poin
ts which appear to be possible candidates for finite temperature symmetry
breaking in d=2.\n
LOCATION:https://researchseminars.org/talk/QASTM/3/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Leonardo Senatore (Institute for Theoretical Physics\, Stanford Un
iversity\, California\, USA)
DTSTART;VALUE=DATE-TIME:20200521T150000Z
DTEND;VALUE=DATE-TIME:20200521T163000Z
DTSTAMP;VALUE=DATE-TIME:20230208T074105Z
UID:QASTM/4
DESCRIPTION:Title: Fr
om $\\lambda\\phi^4$ in dS to how inflation starts out of inhomogenous ini
tial conditions\nby Leonardo Senatore (Institute for Theoretical Physi
cs\, Stanford University\, California\, USA) as part of Quantum Aspects of
Space-Time and Matter\n\n\nAbstract\nI will first describe how we develop
a systematic formalism to compute correlation functions of massless scala
r fields in de Sitter space. Time permitting\, I will then show how\, usin
g a combination of numerical techniques as well as techniques from differ
ential geometry\, we are shedding light on how inflation starts out of inh
omogenous initial conditions.\n
LOCATION:https://researchseminars.org/talk/QASTM/4/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Guilherme Leite Pimentel (University of Amsterdam and Leiden Unive
rsity\, Netherlands)
DTSTART;VALUE=DATE-TIME:20200525T120000Z
DTEND;VALUE=DATE-TIME:20200525T133000Z
DTSTAMP;VALUE=DATE-TIME:20230208T074105Z
UID:QASTM/5
DESCRIPTION:Title: Bo
otstrapping cosmological fluctuations\nby Guilherme Leite Pimentel (Un
iversity of Amsterdam and Leiden University\, Netherlands) as part of Quan
tum Aspects of Space-Time and Matter\n\n\nAbstract\nI will describe a new
method to compute and constrain the possible shapes of primordial correlat
ion functions from inflation. This ``cosmological bootstrap” draws inspi
ration from the recent advances\nin understanding the tree-level S-matrix
in flat space\, as well as the conformal bootstrap of phase transitions. I
will also comment on various unexplored directions for future research.\n
LOCATION:https://researchseminars.org/talk/QASTM/5/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Eva Silverstein (Institute for Theoretical Physics\, Stanford Univ
ersity\, California\, USA)
DTSTART;VALUE=DATE-TIME:20200528T150000Z
DTEND;VALUE=DATE-TIME:20200528T163000Z
DTSTAMP;VALUE=DATE-TIME:20230208T074105Z
UID:QASTM/6
DESCRIPTION:Title: Mu
ltipoint correlators in multifield cosmology: formal structure and applica
tions\nby Eva Silverstein (Institute for Theoretical Physics\, Stanfor
d University\, California\, USA) as part of Quantum Aspects of Space-Time
and Matter\n\n\nAbstract\nConnected N-point amplitudes in quantum field th
eory are\nenhanced by a factor of N! inappropriate regimes of kinematics a
nd\ncouplings\, but the non-perturbative analysis of this for collider\nph
ysics applications is subtle. We will start by briefly reviewing\nthis ef
fect and related developments in large-charge sectors of\nquantum field th
eory. We then resolve the question in the affirmative\nfor N-point correl
ation functions of cosmological perturbations in\nmultifield inflation and
comment on its application to primordial\nnon-Gaussianity. We find that t
hey are calculably N!-enhanced using a\nsimple model for the mixing of the
field sectors which leads to a\nconvolution of their probability distribu
tions. This effect leads to\nmodel-dependent but interesting prospects for
enhanced observational\nsensitivity. Additional spinoffs include applica
tions to primordial\nblack hole production and a new inflationary model wi
th a controlled\nresummation of derivative interactions.\n
LOCATION:https://researchseminars.org/talk/QASTM/6/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Matias Zaldarriaga (School of Natural Sciences\, Astrophysics and
Cosmology\, Institute for Advanced Studies\, Princeton\, USA)
DTSTART;VALUE=DATE-TIME:20200601T130000Z
DTEND;VALUE=DATE-TIME:20200601T150000Z
DTSTAMP;VALUE=DATE-TIME:20230208T074105Z
UID:QASTM/7
DESCRIPTION:Title: Ch
allenges for physical cosmology after Planck\nby Matias Zaldarriaga (S
chool of Natural Sciences\, Astrophysics and Cosmology\, Institute for Adv
anced Studies\, Princeton\, USA) as part of Quantum Aspects of Space-Time
and Matter\n\n\nAbstract\nI will summarize the current state of physical c
osmology. I will describe the open questions that remain and the challenge
s that need to be overcome to make progress.\n
LOCATION:https://researchseminars.org/talk/QASTM/7/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Harmann Nicolai (Director and Senior Professor\, Max Planck Instit
ute for Gravitational Physics\, Potsdam\, Germany)
DTSTART;VALUE=DATE-TIME:20200604T120000Z
DTEND;VALUE=DATE-TIME:20200604T133000Z
DTSTAMP;VALUE=DATE-TIME:20230208T074105Z
UID:QASTM/8
DESCRIPTION:Title: E1
0 Cosmology\nby Harmann Nicolai (Director and Senior Professor\, Max P
lanck Institute for Gravitational Physics\, Potsdam\, Germany) as part of
Quantum Aspects of Space-Time and Matter\n\n\nAbstract\nIn this talk\, I w
ill review work done with A. Kleinschmidt (hep-th/0511290)\, where it is s
hown how to construct simple exact cosmological solutions to the E10/K(E10
)coset model by exploiting its integrability. Using the known corresponden
ces with the bosonic sectors of maximal supergravity theories\, these exac
t solutions translate to exact cosmological solutions of M theory\, first
found by Townsend and Wohlfarth\, and Ohta\, exhibiting intermittent perio
ds of accelerated expansion.\n
LOCATION:https://researchseminars.org/talk/QASTM/8/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Axel Kleinschmidt (Professor and Senior Scientist\, Quantum Gravit
y and Unified Theories Group\, Max Planck Institute for Gravitational Phys
ics\, Potsdam\, Germany)
DTSTART;VALUE=DATE-TIME:20200608T130000Z
DTEND;VALUE=DATE-TIME:20200608T143000Z
DTSTAMP;VALUE=DATE-TIME:20230208T074105Z
UID:QASTM/9
DESCRIPTION:Title: Ge
nerating series for closed string scattering at genus one\nby Axel Kle
inschmidt (Professor and Senior Scientist\, Quantum Gravity and Unified Th
eories Group\, Max Planck Institute for Gravitational Physics\, Potsdam\,
Germany) as part of Quantum Aspects of Space-Time and Matter\n\n\nAbstract
\nThe low-energy limit of closed string scattering amplitudes has recently
received an increased amount of attention due to new connections to numbe
r theory and automorphic forms that I will explain in this talk. The low-e
nergy expansion for n-point scattering can be formulated in terms of objec
ts called modular graph forms. Writing down these forms is easy but analys
ing them less so since they satisfy an intricate web of surprising relatio
ns. I will discuss recent progress on systematising their properties based
on generating function techniques and comment on a relation between open
and closed string scattering. The talk is mainly based on 1911.03476 and 2
004.05156.\n
LOCATION:https://researchseminars.org/talk/QASTM/9/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Sumit R. Das (Professor\, Kentucky University\, USA)
DTSTART;VALUE=DATE-TIME:20200611T133000Z
DTEND;VALUE=DATE-TIME:20200611T153000Z
DTSTAMP;VALUE=DATE-TIME:20230208T074105Z
UID:QASTM/10
DESCRIPTION:Title: Q
UANTUM QUENCH AND EMERGENT SPACE-TIMES\nby Sumit R. Das (Professor\, K
entucky University\, USA) as part of Quantum Aspects of Space-Time and Mat
ter\n\n\nAbstract\nWe will discuss some aspects of scaling in quantum quen
ch and its realization in holography. We then consider quantum quench in t
he singlet sector of the c=1 Matrix Model and map out the emergent dual sp
ace-time. As expected the late time s[ace-time does not contain black hole
s. Rather\, they generically have space-like regions of large coupling ana
logous to cosmological singularities.\n
LOCATION:https://researchseminars.org/talk/QASTM/10/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Igor R. Klebanov (Professor\, Princeton University\, USA)
DTSTART;VALUE=DATE-TIME:20200615T133000Z
DTEND;VALUE=DATE-TIME:20200615T153000Z
DTSTAMP;VALUE=DATE-TIME:20230208T074105Z
UID:QASTM/11
DESCRIPTION:Title: B
reaking of Discrete and Continuous Symmetries in SYK-like Models\nby I
gor R. Klebanov (Professor\, Princeton University\, USA) as part of Quantu
m Aspects of Space-Time and Matter\n\n\nAbstract\nA Majorana fermion is th
e most elemental quantum degree of freedom – a pair of them has only two
quantum states. Yet\, a large number of fermions with interactions coupli
ng four of them at a time can exhibit interesting quantum dynamics. Models
of this kind include the Sachdev-Ye-Kitaev (SYK) model\, where the coeffi
cients of quartic interactions are randomly distributed\, and the Tensor m
odels\, where they respect continuous symmetries. These models exhibit app
roximate invariance under scaling of the time and have power law fall-off
of the correlation functions. In this talk we will discuss a pair of SYK o
r Tensor models coupled by the quartic interactions\, and show that they p
roduce a richer set of phenomena. These include a line of fixed points\, w
here critical exponents vary along the line and formally acquire imaginary
parts outside it. For one sign of the coupling constant\, the approximate
scale invariance continues to hold. For the other\, a gap opens in the en
ergy spectrum\, resulting in exponential fall-off of correlation functions
. This is indicative of breaking of a discrete symmetry. Thus\, our quantu
m mechanical model exhibits dynamical phenomena characteristic of higher d
imensional quantum field theories. Furthermore\, the gapped phase of our m
odel may be dual to a certain traversable wormhole in two-dimensional spac
e-time. The talk will end with a similar discussion of a pair of complex S
YK models coupled by a quartic interaction which preserves the U(1) x U(1)
symmetry. For a range of parameters\, this model gives rise to breaking o
f one of the U(1) symmetries. This is demonstrated via an analysis of the
large N Dyson-Schwinger equations\, as well as by Exact Diagonalizations o
f the finite N Hamiltonians.\n
LOCATION:https://researchseminars.org/talk/QASTM/11/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Daniele Oriti (Professor\, Arnold Sommerfeld Center for Theoretica
l Physics • Ludwig-Maximilians-Universität (LMU) München)
DTSTART;VALUE=DATE-TIME:20200618T120000Z
DTEND;VALUE=DATE-TIME:20200618T140000Z
DTSTAMP;VALUE=DATE-TIME:20230208T074105Z
UID:QASTM/12
DESCRIPTION:Title: W
hat is space? what is time? the quest for quantum gravity\nby Daniele
Oriti (Professor\, Arnold Sommerfeld Center for Theoretical Physics • Lu
dwig-Maximilians-Universität (LMU) München) as part of Quantum Aspects o
f Space-Time and Matter\n\n\nAbstract\nWe introduce the problem of quantum
gravity\, its motivations and challenges at the conceptual as well as phy
sical level. In particular\, we emphasize how constructing a new consisten
t quantum theory of the gravitational field implies deepening our understa
nding of the nature of space and time themselves. We overview existing the
oretical approaches and proposals\, and some recent results. Among the mos
t recent suggestions\, we illustrate the idea that spacetime itself could
be understood as an emergent notion\, and that geometry and topology may f
ind their root in quantum entanglement. Finally\, we illustrate some of th
e general points by discussing one specific quantum gravity formalism\, so
-called group field theories\, a promising recent blend (and evolution) of
matrix/tensor models\, loop quantum gravity and lattice quantum gravity\,
we discuss how cosmology could be understood\, from a quantum gravity per
spective\, and how effective cosmological equations can be extracted from
group field theories.\n
LOCATION:https://researchseminars.org/talk/QASTM/12/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Jared Kaplan (Professor\, Johns Hopkins University\, USA)
DTSTART;VALUE=DATE-TIME:20200622T133000Z
DTEND;VALUE=DATE-TIME:20200622T153000Z
DTSTAMP;VALUE=DATE-TIME:20230208T074105Z
UID:QASTM/13
DESCRIPTION:Title: M
achine Learning and How Physicists Can Think About It\nby Jared Kaplan
(Professor\, Johns Hopkins University\, USA) as part of Quantum Aspects o
f Space-Time and Matter\n\n\nAbstract\nIn the last eight years there has b
een an explosion of progress in Machine Learning. In this colloquium I'll
explain the (very simple) ideas underlying Neural Networks\, and give a f
ew examples of their structure and current capabilities. Then I'll survey
the increasing scales of data and computation in this field\, and make so
me comparisons and projections to see where it could be headed. If time p
ermits\, I'll also discuss my recent work on scaling laws for machine lear
ning\, and its connection to language models and GPT-3.\n
LOCATION:https://researchseminars.org/talk/QASTM/13/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Max Zimet (Center for the Fundamental Laws of Nature High Energy T
heory Group and Black Hole initiative fellow\, Harvard University\, Boston
\, USA)
DTSTART;VALUE=DATE-TIME:20200625T130000Z
DTEND;VALUE=DATE-TIME:20200625T150000Z
DTSTAMP;VALUE=DATE-TIME:20230208T074105Z
UID:QASTM/14
DESCRIPTION:Title: K
3 metrics\nby Max Zimet (Center for the Fundamental Laws of Nature Hig
h Energy Theory Group and Black Hole initiative fellow\, Harvard Universit
y\, Boston\, USA) as part of Quantum Aspects of Space-Time and Matter\n\n\
nAbstract\nI will explain the recent physically motivated construction of
Ricci-flat K3 metrics in 2006.02435\, which gives the first examples of Ri
cci-flat metrics on compact non-toroidal Calabi-Yau manifolds. I will also
relate it — both physically and mathematically — to a second such con
struction\, which is as yet not completely explicit: the missing data is t
he BPS index of a little string theory on $T^2$. In particular\, I will sh
ow that these discrete invariants may be extracted from the metrics produc
ed by the first approach.\n
LOCATION:https://researchseminars.org/talk/QASTM/14/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Aninda Sinha (CHEP\, IISC\, Bengaluru)
DTSTART;VALUE=DATE-TIME:20200702T120000Z
DTEND;VALUE=DATE-TIME:20200702T143000Z
DTSTAMP;VALUE=DATE-TIME:20230208T074105Z
UID:QASTM/16
DESCRIPTION:Title: B
ootstrapping CFTs and QFTs\nby Aninda Sinha (CHEP\, IISC\, Bengaluru)
as part of Quantum Aspects of Space-Time and Matter\n\n\nAbstract\nI will
review some recent developments in the bootstrap approach towards understa
nding quantum field theories. I will begin by using the bootstrap to do ep
silon expansion ala Wilson-Fisher to calculate critical exponents and OPE
coefficients (relevant for the 3d Ising model)—the latter being somethin
g that is difficult to calculate using traditional Feynman diagram approac
h. This is an example of a conformal field theory and will use techniques
of the conformal bootstrap. Then I will discuss some recent work to constr
ain the space of S-matrices for pion scattering in the standard model of p
article physics using the recent reincarnation of the S-matrix bootstrap.
In the course\, I will also introduce and examine certain quantum informat
ion ideas which will aid us in understanding the space of S-matrices.\n
LOCATION:https://researchseminars.org/talk/QASTM/16/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Fernando Quevedo (Department of Applied Mathematics and Theoretica
l Physics (DAMTP)\, University of Cambridge\, UK)
DTSTART;VALUE=DATE-TIME:20200629T120000Z
DTEND;VALUE=DATE-TIME:20200629T143000Z
DTSTAMP;VALUE=DATE-TIME:20230208T074105Z
UID:QASTM/17
DESCRIPTION:Title: S
tring Theory Cosmology Before\, During and After Inflation\nby Fernand
o Quevedo (Department of Applied Mathematics and Theoretical Physics (DAMT
P)\, University of Cambridge\, UK) as part of Quantum Aspects of Space-Tim
e and Matter\n\n\nAbstract\nAn overview is given of ideas incorporating th
e inflationary scenario in string theory. The physics of moduli fields fro
m string theory is used to address questions about the origin of inflation
\, its realization\, and the physics after inflation.\n
LOCATION:https://researchseminars.org/talk/QASTM/17/
END:VEVENT
BEGIN:VEVENT
SUMMARY:James Sully (String Theory Group\, Department of Physics and Astro
nomy\, University of British Columbia\, Vancouver\, British Columbia\, Can
ada)
DTSTART;VALUE=DATE-TIME:20200706T150000Z
DTEND;VALUE=DATE-TIME:20200706T173000Z
DTSTAMP;VALUE=DATE-TIME:20230208T074105Z
UID:QASTM/18
DESCRIPTION:Title: E
igenstate thermalization and disorder averaging in gravity\nby James S
ully (String Theory Group\, Department of Physics and Astronomy\, Universi
ty of British Columbia\, Vancouver\, British Columbia\, Canada) as part of
Quantum Aspects of Space-Time and Matter\n\n\nAbstract\nIt has long been
believed that progress in understanding the black hole information paradox
would require coming to terms with microscopic details of quantum gravity
---something beyond the reach of semiclassical effective field theory. In
that light\, one of the most surprising discoveries of the last year has b
een that signature features of the unitary evaporation of black holes can
already be seen within effective field theory\, albeit with the inclusion
of 'euclidean wormholes'. However\, these novel contributions are best und
erstood when the gravitational theory is not a single microscopic theory\,
but an average over many different theories. To save unitarity must we th
en simultaneously throw it away? I will explain how the same story can be
recovered within a single microscopic theory by thinking carefully about t
he right effective theory for finite-lifetime observers.\n
LOCATION:https://researchseminars.org/talk/QASTM/18/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Paolo Creminelli (Head\, High Energy\, Cosmology and Astroparticle
Physics (HECAP)\, The Abdus Salam International Centre for Theoretical Ph
ysics (ICTP)\, Trieste\, Italy)
DTSTART;VALUE=DATE-TIME:20200709T120000Z
DTEND;VALUE=DATE-TIME:20200709T143000Z
DTSTAMP;VALUE=DATE-TIME:20230208T074105Z
UID:QASTM/19
DESCRIPTION:Title: I
nitial Conditions for Inflation\nby Paolo Creminelli (Head\, High Ener
gy\, Cosmology and Astroparticle Physics (HECAP)\, The Abdus Salam Interna
tional Centre for Theoretical Physics (ICTP)\, Trieste\, Italy) as part of
Quantum Aspects of Space-Time and Matter\n\n\nAbstract\nCosmic inflation
makes the universe flat and homogeneous\, but under what conditions inflat
ion starts? I will discuss analytical results that show\, with weak assump
tions\, that inflation starts somewhere and some theorems in 2+1 and 3+1 d
imensions that support the de Sitter no-hair conjecture.\n
LOCATION:https://researchseminars.org/talk/QASTM/19/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Eugenio Bianchi (Department of Physics and Institute for Gravitati
on & the Cosmos Center for Fundamental Theory\, Pennsylvania State Univers
ity\, Pennsylvania\, USA)
DTSTART;VALUE=DATE-TIME:20200713T130000Z
DTEND;VALUE=DATE-TIME:20200713T153000Z
DTSTAMP;VALUE=DATE-TIME:20230208T074105Z
UID:QASTM/20
DESCRIPTION:Title: T
ypicality of Small Spins in Primordial Black Holes: from the Bekenstein-Ha
wking Entropy to Gravitational Wave Observations\nby Eugenio Bianchi (
Department of Physics and Institute for Gravitation & the Cosmos Center fo
r Fundamental Theory\, Pennsylvania State University\, Pennsylvania\, USA)
as part of Quantum Aspects of Space-Time and Matter\n\n\nAbstract\nBlack
hole entropy is a robust prediction of quantum gravity with no explored ph
enomenological consequences to date. In this talk\, I discuss how the Beke
nstein-Hawking entropy formula allows us to determine the probability dist
ribution of the spin of black holes produced by the collapse of perturbati
ons distributed according to a general relativistic microcanonical ensembl
e. I will also discuss why this ensemble is relevant for black holes forme
d in the early universe\, resulting in a population of black holes with ze
ro spin. In principle\, the identification of such a population at LIGO\,
Virgo\, and future gravitational wave observatories could provide the firs
t observational evidence for the statistical nature of black hole entropy.
\n
LOCATION:https://researchseminars.org/talk/QASTM/20/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Cliff Burgess (Department of Physics & Astronomy\, McMaster Univer
sity and Perimeter Institute for Theoretical Physics (PITP)\, Canada)
DTSTART;VALUE=DATE-TIME:20200716T133000Z
DTEND;VALUE=DATE-TIME:20200716T160000Z
DTSTAMP;VALUE=DATE-TIME:20230208T074105Z
UID:QASTM/21
DESCRIPTION:Title: S
caling the Landscape: Robust EFT Implications from UV Physics\nby Clif
f Burgess (Department of Physics & Astronomy\, McMaster University and Per
imeter Institute for Theoretical Physics (PITP)\, Canada) as part of Quant
um Aspects of Space-Time and Matter\n\n\nAbstract\nThe phenomenon of decou
pling is a two-edged sword: it allows a robust understanding of low-energy
physics without requiring detailed knowledge of UV completions\, but by d
oing so it also hides any clues about these completions from prying low-en
ergy eyes. There is widespread interest in finding any UV diamonds amongst
the low-energy roughage\, however\, as is illustrated by the `swampland
’ program. This program promotes the perceived difficulties in finding p
henomenologically successful mechanisms (eg cosmic inflation) in string th
eory into a principle\, by asserting that some low-energy theories do not
have UV completions\, so the UV information lies in what can and cannot be
completed. This talk takes a different approach\, arguing that EFTs comin
g from weakly coupled strings enjoy a pattern of approximate scaling symme
tries\, and it is these symmetries and their pattern of breaking that prov
ide the robust UV information that is accessible at low energies. We argue
that these symmetries (together with other low-energy symmetries) account
for the widespread occurrence of no-scale supergravities in 4D string vac
ua\, and encode attractive new mechanisms for technical naturalness. In pa
rticular\, the symmetries themselves account for the rarity of (but do not
predict the absence of) inflationary vacua\, and the models to which they
point include an enormously successful class of technically natural infla
tionary models (not based on axions) that come with potentially testable i
mplications for the search for primordial gravity waves.\n
LOCATION:https://researchseminars.org/talk/QASTM/21/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Vijay Balasubramanian (Department of Physics and Astronomy\, Univ
ersity of Pennsylvania School of Arts and Sciences\, Philadelphia\, USA)
DTSTART;VALUE=DATE-TIME:20200720T133000Z
DTEND;VALUE=DATE-TIME:20200720T160000Z
DTSTAMP;VALUE=DATE-TIME:20230208T074105Z
UID:QASTM/22
DESCRIPTION:Title: T
he black hole information paradox\nby Vijay Balasubramanian (Departmen
t of Physics and Astronomy\, University of Pennsylvania School of Arts an
d Sciences\, Philadelphia\, USA) as part of Quantum Aspects of Space-Time
and Matter\n\n\nAbstract\nFor nearly half a century\, physicists have aske
d whether and how we can recover information falling into black holes in o
rder to guarantee the unitarity of quantum physics. In this talk\, I will
review progress we have made towards solving this puzzle. This progress
includes: (a) identifying the quantum gravity microstates for some black
holes\; (b) showing that information about the microstates is available\,
but difficult to detect\, outside the black hole\; (c) identifying the rol
e of chaos in scrambling information into the microstates\; (d) explaining
the role of quantum entanglement in information encoding by black holes a
nd by Hawking radiation\; (e) understanding geometrization of information
in gravity\; and\, finally\, (f) uncovering connections with basic proble
ms in information theory\, quantum computation\, and complexity theory.\n
LOCATION:https://researchseminars.org/talk/QASTM/22/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Brian Swingle (Department of Physics and The Joint Center for Quan
tum Information and Computer Science\, University of Maryland\, College Pa
rk\, Maryland\, USA)
DTSTART;VALUE=DATE-TIME:20200723T130000Z
DTEND;VALUE=DATE-TIME:20200723T153000Z
DTSTAMP;VALUE=DATE-TIME:20230208T074105Z
UID:QASTM/23
DESCRIPTION:Title: C
onformal field theories are magical\nby Brian Swingle (Department of P
hysics and The Joint Center for Quantum Information and Computer Science\,
University of Maryland\, College Park\, Maryland\, USA) as part of Quantu
m Aspects of Space-Time and Matter\n\n\nAbstract\nStabilizer states are an
important subclass of quantum states that play an important role in quant
um error correction\, topological order\, and toy models of holography\, a
mong many other applications. It is also important to quantify the extent
to which a given state lies beyond the stabilizer set\, a resource known a
s magic. I will discuss the concept of magic and some of its measures in m
any-body physics\, focusing on a particular 1d spin chain which flows to a
conformal field theory in the infrared. Based on a work to appear with Ch
ristopher White and Charles Cao.\n
LOCATION:https://researchseminars.org/talk/QASTM/23/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Geoffrey Penington (Stanford Institute for Theoretical Physics\, S
tanford University\, California\, USA)
DTSTART;VALUE=DATE-TIME:20200727T150000Z
DTEND;VALUE=DATE-TIME:20200727T173000Z
DTSTAMP;VALUE=DATE-TIME:20230208T074105Z
UID:QASTM/24
DESCRIPTION:Title: T
he Replica Trick in Quantum Gravity: From the Ryu-Takayanagi formula to Is
lands\nby Geoffrey Penington (Stanford Institute for Theoretical Physi
cs\, Stanford University\, California\, USA) as part of Quantum Aspects of
Space-Time and Matter\n\n\nAbstract\nStarting with the famous Lewkowycz-M
aldacena derivation of the Ryu-Takayanagi formula\, the replica trick has
played a central role in teaching us about entanglement and entropy in qua
ntum gravity. I will review these ideas\, showing how a semiclassical anal
ysis leads to the quantum extremal surface prescription\, entanglement wed
ge reconstruction\, and eventually to the recent derivations of the Page c
urve in evaporating black holes.\n
LOCATION:https://researchseminars.org/talk/QASTM/24/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Robert Myers (Perimeter Institute for Theoretical Physics\, Waterl
oo\, Ontario\, Canada)
DTSTART;VALUE=DATE-TIME:20200730T133000Z
DTEND;VALUE=DATE-TIME:20200730T160000Z
DTSTAMP;VALUE=DATE-TIME:20230208T074105Z
UID:QASTM/25
DESCRIPTION:Title: Q
uantum Extremal Islands Made Easy\nby Robert Myers (Perimeter Institut
e for Theoretical Physics\, Waterloo\, Ontario\, Canada) as part of Quantu
m Aspects of Space-Time and Matter\n\n\nAbstract\nWe illustrate the appear
ance of quantum extremal islands in holographic setups in higher dimension
s. We emphasize the close parallel with the behaviour of holographic entan
glement entropy in more familiar settings.\n
LOCATION:https://researchseminars.org/talk/QASTM/25/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Ravi K. Sheth (Department of Physics and Astronomy\, University o
f Pennsylvania School of Arts and Sciences\, Philadelphia\, USA\, and Rese
arch Staff Associate at ICTP\, Trieste\, Italy)
DTSTART;VALUE=DATE-TIME:20200731T133000Z
DTEND;VALUE=DATE-TIME:20200731T160000Z
DTSTAMP;VALUE=DATE-TIME:20230208T074105Z
UID:QASTM/26
DESCRIPTION:Title: A
robust standard rod for cosmology\nby Ravi K. Sheth (Department of Ph
ysics and Astronomy\, University of Pennsylvania School of Arts and Scien
ces\, Philadelphia\, USA\, and Research Staff Associate at ICTP\, Trieste\
, Italy) as part of Quantum Aspects of Space-Time and Matter\n\n\nAbstract
\nBaryon Acoustic Oscillations provide a standard rod for constraining cos
mological distances and the expansion history of our universe over a subst
antial fraction of its history. I will review the physics which motivates
this standard rod and summarize constraints from its use. Finally\, I wi
ll discuss ways of making the rod more robust so that it can more easily b
e used to constrain non-standard cosmological models. This is particularl
y important given recent tension between local and distant estimates of th
e Hubble constant.\n
LOCATION:https://researchseminars.org/talk/QASTM/26/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Alexander Vilenkin (Professor\, Tufts University)
DTSTART;VALUE=DATE-TIME:20200813T133000Z
DTEND;VALUE=DATE-TIME:20200813T160000Z
DTSTAMP;VALUE=DATE-TIME:20230208T074105Z
UID:QASTM/27
DESCRIPTION:Title: B
lack holes from cosmic inflation\nby Alexander Vilenkin (Professor\, T
ufts University) as part of Quantum Aspects of Space-Time and Matter\n\n\n
Abstract\nCosmic inflation is a period of rapid\, accelerated expansion in
the early history of the universe. Inflation explains some puzzling featu
res of the big bang that had to be postulated before and makes predictions
that have been confirmed by observations. In this talk\, I will argue tha
t inflation generically predicts the formation of black holes with a very
wide spectrum of masses. This effect may account for supermassive black ho
les observed at the centers of most galaxies\, for black hole mergers obse
rved by the LIGO interferometer\, and for the mysterious dark matter. It a
lso has important implications for the global structure of the universe.\n
LOCATION:https://researchseminars.org/talk/QASTM/27/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Tadashi Takayanagi (YITP)
DTSTART;VALUE=DATE-TIME:20201116T130000Z
DTEND;VALUE=DATE-TIME:20201116T153000Z
DTSTAMP;VALUE=DATE-TIME:20230208T074105Z
UID:QASTM/28
DESCRIPTION:Title: R
ecent Progresses of AdS/BCFT\nby Tadashi Takayanagi (YITP) as part of
Quantum Aspects of Space-Time and Matter\n\n\nAbstract\nIn this lecture\,
I would like to review recent progresses of holography for conformal field
theories on manifolds with boundaries\, which is called as AdS/BCFT. Afte
r we introduce the AdS/BCFT construction\, we would like to introduce the
holographic entanglement entropy and entanglement wedges in AdS/BCFT\, whi
ch provided one of the important ideas behind the recent Island formula. F
inally\, we would like to explain our recent work about codimension two ho
lography\, called wedge holography as an application of AdS/BCFT. \n\nZoom
inar link: https://mpi-aei.zoom.us/j/97623339163\n
LOCATION:https://researchseminars.org/talk/QASTM/28/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Pedro Vieira (Perimeter Institute)
DTSTART;VALUE=DATE-TIME:20201123T140000Z
DTEND;VALUE=DATE-TIME:20201123T163000Z
DTSTAMP;VALUE=DATE-TIME:20230208T074105Z
UID:QASTM/29
DESCRIPTION:Title: I
ntegrability in AdS/CFT\nby Pedro Vieira (Perimeter Institute) as part
of Quantum Aspects of Space-Time and Matter\n\n\nAbstract\nWe are close t
o having a full solution to a quantum field theory in four dimensions and
its associated string theory dual. I will review some of the exciting elem
ents of this solution where Integrability and Holography play a key role.\
n\nZoominar link: https://mpi-aei.zoom.us/j/97623339163\n
LOCATION:https://researchseminars.org/talk/QASTM/29/
END:VEVENT
END:VCALENDAR