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BEGIN:VEVENT
SUMMARY:Toward realistic de Sitter heterotic-string models with stable mod
uli
DTSTART;VALUE=DATE-TIME:20221207T073000Z
DTEND;VALUE=DATE-TIME:20221207T083000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3872@conference-indico.kek.jp
DESCRIPTION:Speakers: Alon Faraggi (University of Liverpool)\nThe Standard
Model of particle physics accounts for all experimental observations to d
ate\, and may provide viable parameterisation up to the Planck scale. In t
his eventuality\, further insight into the fundamental origin of the Stand
ard Model parameters can only be gleaned by synthesising it with gravity.
String theory provides a framework for the construction of phenomenologica
l models that are consistent with perturbative quantum gravity. Since the
late eighties quasi-realistic supersymmetric string models were constructe
d that reproduce the structure of the Minimal Supersymmetric Standard Mode
ls and provide the arena for calculating the parameters of the Standard Mo
del from a theory of quantum gravity. In recent years these studies were e
xtended to non-supersymmetric string vacua including tachyon free vacua th
at descends from tachyonic ten dimensional vacua. I will give an overview
of this work\, including work in progress toward the construction of quasi
-realistic de Sitter vacua with stable moduli.\n\nhttps://conference-indic
o.kek.jp/event/181/contributions/3872/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3872/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Holography of information and the black-hole information paradox
DTSTART;VALUE=DATE-TIME:20221209T070000Z
DTEND;VALUE=DATE-TIME:20221209T083000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3869@conference-indico.kek.jp
DESCRIPTION:Speakers: Suvrat Raju (ICTS)\nWe review recent progress in our
understanding of how information is localized in a theory of quantum grav
ity. In such theories\, we argue that\, subject to weak assumptions\, info
rmation in any bounded region is also available in its complement. This is
very different from the manner in which quantum information is localized
in nongravitational quantum field theories. This implies that the so-calle
d split property fails in theories of quantum gravity. We show how this ob
servation leads to the identification of an error in Hawking's argument fo
r information loss and a resolution of some paradoxes about black holes.\n
References:\n1) Lessons from the Information Paradox\, Phys.Rept. 943 (202
2)\, [arXiv:2012.05770]\n2) Failure of the split property in gravity and t
he information paradox\, Class.Quant.Grav. 39 (2022)\, [arXiv:2110.05470]\
n\nhttps://conference-indico.kek.jp/event/181/contributions/3869/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3869/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Constructions of Non-SUSY String Vacua with Vanishing Cosmological
Constant
DTSTART;VALUE=DATE-TIME:20221209T040000Z
DTEND;VALUE=DATE-TIME:20221209T044000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3876@conference-indico.kek.jp
DESCRIPTION:Speakers: Yuji Sugawara (Ritsumeikan University)\nIn this talk
\, I discuss how one can systematically construct non-supersymmetric strin
g vacua with vanishing cosmological constant at one loop\, founded mainly
on a series of my works. After making a review of related studies\, I pre
sent the constructions of the string vacua possessing such a property base
d on the asymmetric orbifolds in various CFT set-ups. We further discuss t
he physical aspects of these vacua.\n\nhttps://conference-indico.kek.jp/ev
ent/181/contributions/3876/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3876/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Expanding Edges of Quantum Hall Systems in a Cosmology Language -
Hawking Radiation from de Sitter Horizon in Edge Modes
DTSTART;VALUE=DATE-TIME:20221209T012000Z
DTEND;VALUE=DATE-TIME:20221209T022000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3866@conference-indico.kek.jp
DESCRIPTION:Speakers: Masahiro Hotta (Tohoku University)\nExpanding edge e
xperiments are promising to open new physics windows of quantum Hall syste
ms. In a static edge\, the edge excitation\, which is described by free fi
elds decoupled with the bulk dynamics\, is gapless\, and the dynamics pres
erve conformal symmetry. When the edge expands\, such properties need not
be preserved. We formulate a quantum field theory in 1+1 dimensional curve
d spacetimes to analyze the edge dynamics. We propose methods to address t
he following questions using edge waveforms from the expanding region: Doe
s the conformal symmetry survive? Is the nonlinear interaction of the edge
excitations induced by edge expansion? Do the edge excitations interact w
ith the bulk excitations? We additionally show that the expanding edges ca
n be regarded as expanding universe simulators of two-dimensional dilaton-
gravity models\, including the Jackiw-Teitelboim gravity model. As an appl
ication\, we point out that our theoretical setup might simulate emission
of analog Hawking radiation with the Gibbons-Hawking temperature from the
future de Sitter horizon formed in the expanding edge region.\n\nhttps://c
onference-indico.kek.jp/event/181/contributions/3866/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3866/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Quantum Superpositions of Massive Bodies and Gravitationally Media
ted Entanglement
DTSTART;VALUE=DATE-TIME:20221209T000000Z
DTEND;VALUE=DATE-TIME:20221209T010000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3865@conference-indico.kek.jp
DESCRIPTION:Speakers: Robert Wald (University of Chicago)\nIn order to avo
id contradictions with complementarity and causality in a gedankenexperime
nt involving a quantum superposition of a massive body\, it was previously
shown (in arXiv:1807.07015) that it is necessary for there to be both qua
ntized gravitational radiation and local vacuum fluctuations\nof the space
time metric. We review this gedankenexperiment and the previously given
“back of the envelope” arguments that resolve it. We then improve upo
n this analysis by providing a precise and rigorous description of the ent
anglement and decoherence effects (given in arXiv:2112.10798). As a by-pro
duct of our analysis\, we show that under the protocols of the gedankenexp
eriment\, there is no clear distinction between entanglement mediated by
the Newtonian gravitational field of a body and entanglement mediated by o
n-shell gravitons emitted by the body. This suggests that Newtonian entang
lement implies the existence of graviton entanglement and supports the vie
w that the experimental discovery of Newtonian entanglement—as envisione
d in proposed experiments—may be viewed as evidence for the existence of
the graviton\n\nhttps://conference-indico.kek.jp/event/181/contributions/
3865/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3865/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Stability of open-string models with broken supersymmetry
DTSTART;VALUE=DATE-TIME:20221208T080000Z
DTEND;VALUE=DATE-TIME:20221208T084000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3874@conference-indico.kek.jp
DESCRIPTION:Speakers: Hervé Partouche (Ecole Polytechnique)\nWe consider
type IIB orientifold models in four-dimensional Minkowski spacetime\, with
N=2 supersymmetry spontaneously broken to 0. For an arbitrary choice of D
9- and D5-brane configuration\, we analyze the generation of masses at one
-loop for all open- and closed-string sector moduli fields. In order to fi
nd non-tachyonic models at one-loop\, a key ingredient is to consider bran
e configurations with rigid positions.\n\nhttps://conference-indico.kek.jp
/event/181/contributions/3874/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3874/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Solving the sign problem in the IKKT model and the real-time quant
um evolution by the generalized Lefschetz thimble method
DTSTART;VALUE=DATE-TIME:20221208T022000Z
DTEND;VALUE=DATE-TIME:20221208T030000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3864@conference-indico.kek.jp
DESCRIPTION:Speakers: Jun Nishimura (KEK)\nI report on recent developments
in the generalized thimble method based on the Hybrid Monte Carlo algorit
hm using backpropagation. In particular\, I discuss interesting results fo
r the IKKT matrix model and the real-time evolution in quantum mechanics.\
n\nhttps://conference-indico.kek.jp/event/181/contributions/3864/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3864/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Tensor renormalization group in field theory
DTSTART;VALUE=DATE-TIME:20221208T012000Z
DTEND;VALUE=DATE-TIME:20221208T020000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3863@conference-indico.kek.jp
DESCRIPTION:Speakers: Daisuke Kadoh (Doshisha University)\nRecently\, a no
vel approach using tensor renormalization group (TRG) has made great progr
ess in the numerical computation of lattice field theory. In the TRG\, par
tition functions and correlation functions are represented as tensor netwo
rks. Their values can be evaluated by coarse-graining the network without
using probabilities like Monte Carlo methods. Therefore\, the TRG can easi
ly be applied to systems with sign problems. In this talk\, I review the T
RG method and talk about how it is used in computations of lattice field t
heory.\n\nhttps://conference-indico.kek.jp/event/181/contributions/3863/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3863/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Sign problem and the Worldvolume Hybrid Monte Carlo method
DTSTART;VALUE=DATE-TIME:20221208T000000Z
DTEND;VALUE=DATE-TIME:20221208T010000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3862@conference-indico.kek.jp
DESCRIPTION:Speakers: Masafumi Fukuma (Kyoto University)\nThe numerical si
gn problem is one of the major obstacles to first-principles calculations
in a variety of important systems. Typical examples include finite-density
QCD\, some condensed matter systems such as strongly correlated electron
systems and frustrated spin systems\, and real-time dynamics of quantum fi
elds. Until very recently\, individual methods were developed for each tar
get system\, but over the past decade there has been a movement to find a
versatile solution to the sign problem. In this talk\, starting with the b
asics of Markov chain Monte Carlo methods\, I first explain the essence of
the sign problem and outline some of the approaches proposed in line with
the movement. I then focus on methods based on the Lefschitz thimble\, an
d argue that the "Worldvolume Hybrid Monte Carlo method" [Fukuma and Matsu
moto\, arXiv:2012.08468] is a promising method due to its reliability and
versatility. If I have time\, I also briefly discuss recent topics related
to thimbles\, such as resurgence and quantum cosmology.\n\nhttps://confer
ence-indico.kek.jp/event/181/contributions/3862/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3862/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Neutrino Masses from Generalized Symmetry Breaking
DTSTART;VALUE=DATE-TIME:20221207T040000Z
DTEND;VALUE=DATE-TIME:20221207T050000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3861@conference-indico.kek.jp
DESCRIPTION:Speakers: Kantaro Ohmori (University of Tokyo)\nIt is now unde
rstood that the concept of symmetry in quantum field theory should be vast
ly generalized from the ones come from a group action on fields. The gener
alization includes the higher-form symmetry\, which acts on extended opera
tors\, and non-invertible symmetry\, which does not have an inverse operat
ion. In particular\, a classical symmetry with an ABJ-anomaly with an abel
ian gauge group should be regarded as a non-invertible symmetry. A non-inv
ertible symmetry of this type can naturally be broken by a dynamical monop
ole loop\, and such an effect is non-perturbative. In this talk\, I discus
s the models where this mechanism gives masses to neutrinos. There are two
models\, one of which gives Majorana masses and the other gives Dirac mas
ses. These models contain a $Z’$ vector boson gauging the lepton number
difference $U(1)_{L_\\mu-L_\\tau}$\, which is completed into a non-abelian
group in the further UV. These UV models are relatively simple\; e.g. the
Dirac masses model only contains the standard model fermions and three ri
ght handed neutrinos as its fermion content. Since this work mainly focus
on the absolute magnitude of neutrino masses\, more phenological investiga
tions are desired\, e.g. about texture.\n\nhttps://conference-indico.kek.j
p/event/181/contributions/3861/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3861/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Non-invertible symmetries on the lattice
DTSTART;VALUE=DATE-TIME:20221207T012000Z
DTEND;VALUE=DATE-TIME:20221207T022000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3860@conference-indico.kek.jp
DESCRIPTION:Speakers: Satoshi Yamaguchi (Osaka University)\nRecently\, the
concept of symmetry has been generalized\, and what was not traditionally
called symmetry is now being used similarly as symmetry. In this talk\, w
e discuss a class of such generalized symmetries\, called non-invertible s
ymmetries\, from the viewpoint of the lattice field theories. In particula
r\, we construct topological defects in four-dimensional Z$_2$ lattice gau
ge theory\, including the Kramers-Wannier-Wegner (KWW) duality defect\; th
e KWW defect is an example of non-invertible symmetries. Also\, we conside
r the system with a boundary and discuss the relations between the disk pa
rtition functions derived from the non-invertible symmetry.\n\nhttps://con
ference-indico.kek.jp/event/181/contributions/3860/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3860/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Symmetries in QFT and applications
DTSTART;VALUE=DATE-TIME:20221207T000000Z
DTEND;VALUE=DATE-TIME:20221207T010000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3859@conference-indico.kek.jp
DESCRIPTION:Speakers: Yuya Tanizaki (YITP\, Kyoto University)\nQuantum fie
ld theory is a framework that can describe universal behavior in the low-e
nergy region for quantum many-body systems\, but solving it is often very
difficult as it often becomes strongly coupled systems. One of possible ap
proaches to such problems is to constrain the dynamics from general viewpo
ints instead of solving the dynamics directly. Symmetry in field theories
has played a very important role from this perspective. In recent years\,
the notion of symmetry itself has been generalized in a remarkable manner\
, and such a generalization produces rigorous constraints on strongly-coup
led field theories. In this talk\, the generalized notion of symmetry will
be explained from the basics and some of its applications will be introdu
ced.\n\nhttps://conference-indico.kek.jp/event/181/contributions/3859/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3859/
END:VEVENT
BEGIN:VEVENT
SUMMARY:M2-branes and q-Painleve equations
DTSTART;VALUE=DATE-TIME:20221209T050000Z
DTEND;VALUE=DATE-TIME:20221209T052000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3850@conference-indico.kek.jp
DESCRIPTION:Speakers: Tomoki Nosaka (Kavli Institute for Theoretical Scien
ces\, University of Chinese Academy of Sciences)\nIt is known that the par
tition function of ABJM theory\, the 3d Chern-Simons matter theory on N M2
-branes probing $C^4/Z_k$ orbifold\, solves a non-linear difference relati
on called q-deformed Painleve III system. This connection is motivated wit
h the idea of Painleve/gauge correspondence and the topological string/spe
ctral theory correspondence for the quantization of algebraic curves\, whi
ch also suggests that the similar connection exists for a more general cla
ss of M2-brane theories. As a concrete example\, we present the connection
between the four node circular quiver Chern-Simons theory and the q-defor
med Painleve VI system. We also demonstrate how the partition function of
this theory reduces to the partition function of the ABJM theory under the
coalescence limit of the q-Painleve systems.\n\nhttps://conference-indico
.kek.jp/event/181/contributions/3850/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3850/
END:VEVENT
BEGIN:VEVENT
SUMMARY:6d Seiberg-Witten curves for E-string and Little string theories f
rom 5-brane webs
DTSTART;VALUE=DATE-TIME:20221209T052000Z
DTEND;VALUE=DATE-TIME:20221209T054000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3851@conference-indico.kek.jp
DESCRIPTION:Speakers: Yuji Sugimoto (POSTECH)\nWe propose a systematic way
of obtaining 6d Seiberg-Witten curves from Type IIB 5-brane webs with or
without orientifold planes\, by generalizing the construction of 5d Seiber
g-Witten curves from 5-brane webs. We apply our construction to two kin
ds of theories: 6d E-string theory and little string theory. In particu
lar\, the expression of Seiberg-Witten curve for the E-string theory drast
ically reduces compared with Eguchi-Sakia's curves. The Seiberg-Witten
curve for little string theory that we consider is consistent with the kn
own result. Furthermore\, we discuss some other possibilities which may
define different little string theories.\n\nhttps://conference-indico.kek
.jp/event/181/contributions/3851/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3851/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Axiomatic rational RG flow
DTSTART;VALUE=DATE-TIME:20221209T054000Z
DTEND;VALUE=DATE-TIME:20221209T060000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3852@conference-indico.kek.jp
DESCRIPTION:Speakers: Ken Kikuchi (YMSC)\nWe axiomatize rational massless
renormalization group flow as Kan extension.\n\nhttps://conference-indico.
kek.jp/event/181/contributions/3852/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3852/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Application of Nambu Dynamics to Non-equilibrium thermodynamics
DTSTART;VALUE=DATE-TIME:20221209T060000Z
DTEND;VALUE=DATE-TIME:20221209T062000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3853@conference-indico.kek.jp
DESCRIPTION:Speakers: Yoshiki Matsuoka (The Open University of Japan)\nIn
1973\, Yoichiro Nambu published a GHD paper(titled Generalized Hamitonian
Dynamics). This paper was the beginning of what is now known as Nambu
dynamics. Nambu dynamics is the generalization of Hamiltonian dynamics
involving multiple Hamiltonians\, and has applications to string theory a
nd fluid dynamics. In this talk\, We will present our successful formul
ation of Nambu dynamics applied to Non-equilibrium thermodynamics\, includ
ing the concrete example. The content of this talk is available at arXi
v:2209.08469.\n\nhttps://conference-indico.kek.jp/event/181/contributions/
3853/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3853/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Hierarchical structure of physical Yukawa couplings from matter fi
eld Kaehler metric
DTSTART;VALUE=DATE-TIME:20221209T062000Z
DTEND;VALUE=DATE-TIME:20221209T064000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3854@conference-indico.kek.jp
DESCRIPTION:Speakers: Hajime Otsuka (Kyushu University)\nWe study the impa
cts of matter field Kaehler metric on physical Yukawa couplings in string
compactifications. Since the Kaehler metric is non-trivial in general\,
the kinetic mixing of matter fields opens a new avenue for realizing a
hierarchical structure of physical Yukawa couplings\, even when holomo
rphic Yukawa couplings have the trivial structure. The hierarchical Yukawa
couplings are demonstrated by couplings of pure untwisted modes on toroid
al orbifolds and their resolutions in the context of heterotic string t
heory with standard embedding. Also\, we study the hierarchical couplings
among untwisted and twisted modes on resolved orbifolds.\n\nhttps://con
ference-indico.kek.jp/event/181/contributions/3854/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3854/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Entropy and its conservation in expanding Universe
DTSTART;VALUE=DATE-TIME:20221209T050000Z
DTEND;VALUE=DATE-TIME:20221209T052000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3845@conference-indico.kek.jp
DESCRIPTION:Speakers: Shinya Aoki (Yukawa Institute for Theoretical Physic
s\, Kyoto University)\nWe investigate properties of the conserved charge i
n general relativity\, recently proposed by one of the present authors wit
h his collaborators\, in the inflation era\, the matter dominated era and
the radiation dominated era of the expanding Universe. We show that th
e conserved charge becomes the Bekenstein-Hawking entropy in the inflation
era\, and it becomes the matter entropy and the radiation entropy in the
matter and radiation dominated eras\, respectively\, while the charge itse
lf is always conserved. These properties are qualitatively confirmed by a
numerical analysis of a model with a scalar field and radiations. Resu
lts in this paper provide more evidences on the interpretation that the co
nserved charge in general relativity corresponds to entropy.\n\nhttps://co
nference-indico.kek.jp/event/181/contributions/3845/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3845/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Entropy constraints on effective field theory
DTSTART;VALUE=DATE-TIME:20221209T052000Z
DTEND;VALUE=DATE-TIME:20221209T054000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3846@conference-indico.kek.jp
DESCRIPTION:Speakers: Daiki Ueda (Peking University)\nIn effective field t
heory\, the positivity bounds of higher derivative operators are derived f
rom analyticity\, causality\, and unitarity. We show that the positivity b
ounds on a class of effective field theories\, e.g.\, dimension-eight term
of a single massless scalar field\, the Standard Model Effective Field Th
eory dimension-eight $SU(N)$ gauge bosonic operators\, and Einstein-Maxwel
l theory with higher-derivative operators\, generated by interactions betw
een heavy and light degrees of freedom can be derived by the non-negativit
y of relative entropy. For such a class of effective field theories\, we p
rove that the interactions increase thermodynamic entropy at fixed energy
and charge\, which is intimately connected with the extremality relations
of black holes exhibiting Weak-Gravity-Conjecture. These arguments are app
licable when corrections from the interactions involving higher-derivative
operators of light fields are not dominant in the effective field theorie
s. The entropy constraint is a consequence of the Hermiticity of Hamiltoni
an\, and any theory violating the non-negativity of entropy would not resp
ect the second law of thermodynamics.\n\nhttps://conference-indico.kek.jp/
event/181/contributions/3846/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3846/
END:VEVENT
BEGIN:VEVENT
SUMMARY:No Smooth Beginning for The Universe and Trans-Planckian Physics
DTSTART;VALUE=DATE-TIME:20221209T054000Z
DTEND;VALUE=DATE-TIME:20221209T060000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3847@conference-indico.kek.jp
DESCRIPTION:Speakers: Hiroki Matsui (Yukawa Institute for Theoretical Phys
ics\, Kyoto University)\nIn minisuperspace quantum cosmology\, the Lorentz
ian path integral formulations of the no-boundary and tunneling proposals
have recently been analyzed\, but it has been pointed out that the wave fu
nction of linearized perturbations around a homogeneous and isotropic back
ground is of an inverse Gaussian form and thus that their correlation func
tions are divergent. In this talk\, I will discuss the problem and revisit
this issue of the Lorentzian quantum cosmology by modifying the dispersio
n relation based on trans-Planckian physics. I consider two modified dispe
rsion relations\, the generalized Corley/Jacobson dispersion relation with
higher momentum terms and the Unruh dispersion relation with a trans-Plan
ckian mode cut-off\, as examples\, and show that the inverse Gaussian prob
lem of perturbations in the Lorentzian quantum cosmology is hard to overco
me with minimal modifications of the gravity theory\, such as modifying th
e dispersion relation at short distances.\n\nhttps://conference-indico.kek
.jp/event/181/contributions/3847/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3847/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Numerical study of quantum cosmology by the generalized Lefschetz
thimble method
DTSTART;VALUE=DATE-TIME:20221209T060000Z
DTEND;VALUE=DATE-TIME:20221209T062000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3848@conference-indico.kek.jp
DESCRIPTION:Speakers: Chien Yu Chou (SOKENDAI)\nQuantum cosmology is estab
lished as a way to understand the beginning of universe. Picard-Lefschetz
theory has raised recent interest on the “tunneling from nothing” prop
osal by Vilenkin and the “no boundary” proposal by Hartle-Hawking. The
two proposals can be closely related through analysis on saddle points an
d boundary conditions. In this work\, we demonstrate a first principle cal
culation on the mini-superspace model. We overcome the sign problem arisin
g from the Lorentzian path integral formulation with generalized Lefschetz
thimble method. At the initial time\, we also perform calculations using
the Robin boundary condition\, which interpolates the Dirichlet and Neuman
n boundary conditions. The Stoke’s theorem from Vilenkin to Hartle-Hawki
ng can be shown at the critical value of interpolating factor in Robin bou
ndary condition.\n\nhttps://conference-indico.kek.jp/event/181/contributio
ns/3848/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3848/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Path integrals of perturbative strings on all the curved backgroun
ds from string geometry theory and a potential energy of the backgrounds
DTSTART;VALUE=DATE-TIME:20221209T062000Z
DTEND;VALUE=DATE-TIME:20221209T064000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3849@conference-indico.kek.jp
DESCRIPTION:Speakers: Matsuo Sato (Hirosaki University)\nOne perturbative
string theory is defined on one fixed background. On the other hand\, it i
s necessary that a non-perturbative formulation of string theory includes
all the perturbatively stable vacua and perturbative string theories on va
rious curved backgrounds are derived from the single theory. In this talk\
, we derive perturbative string theories on all the curved backgrounds fro
m the fluctuations around fixed backgrounds in a single string geometry th
eory\, which is one of the candidates of the non-perturbative formulation
of string theory. Furthermore\, we can define a potential energy of the b
ackgrounds because they do not depend on the string geometry time. A backg
round can be determined by minimizing the energy. Because this mechanism
does not depend on supersymmetry\, we can study general compactifications.
We discuss this application to string phenomenology.\n\nhttps://conferenc
e-indico.kek.jp/event/181/contributions/3849/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3849/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Renormalization group approach to cMERA
DTSTART;VALUE=DATE-TIME:20221208T064000Z
DTEND;VALUE=DATE-TIME:20221208T070000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3842@conference-indico.kek.jp
DESCRIPTION:Speakers: Takaaki Kuwahara (Shizuoka University)\nThe MERA has
attracted attention as a model that describes the geometry that emerges f
rom boundary theory. Its continuous version\, the cMERA\, is expected to b
e a method to derive geometry directly from a continuous theory. In free f
ield theories\, the cMERA was successfully constructed based on the variat
ional method. However\, from the holographic point of view\, it is crucial
to construct the cMERA for interacting theories. Since constructing the c
MERA is equivalent to determining the scale dependence of the wavefunction
al\, we consider an approach based on the renormalization group. We first
construct the cMERA perturbatively in interacting scalar theories\, and fu
rthermore\, we derive non-perturbative renormalization group equation for
the wavefunctional.\n\nhttps://conference-indico.kek.jp/event/181/contribu
tions/3842/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3842/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Fluid model of black hole/string transition
DTSTART;VALUE=DATE-TIME:20221208T070000Z
DTEND;VALUE=DATE-TIME:20221208T072000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3843@conference-indico.kek.jp
DESCRIPTION:Speakers: Yoshinori Matsuo (Kindai University)\nWe propose a f
luid model of self-gravitating strings. It is expected that black holes tu
rn into strings around the end of black hole evaporation. The transition w
ill occur near the Hagedorn temperature. After the transition\, strings wo
uld form a bound state by the self-gravitation. Horowitz and Polchinski fo
rmulated a model of self-gravitating strings by using winding strings wrap
ping on the Euclidean time circle. We first show that winding strings in t
he Horowitz-Polchinski model approximately behave as a perfect fluid. Then
\, we solve the Einstein equation for the fluid of winding strings. Our so
lution reproduces behaviors of the self-gravitating string solution in the
Horowitz-Polchinski model near the Hagedorn temperature\, while it approa
ches the Schwarzschild black hole in low temperature. Thus\, our fluid mod
el of self-gravitating strings gives a description of the transition betwe
en black holes and strings.\n\nhttps://conference-indico.kek.jp/event/181/
contributions/3843/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3843/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Krylov complexity of free and interacting scalar QFTs in the conti
nuum limit
DTSTART;VALUE=DATE-TIME:20221208T072000Z
DTEND;VALUE=DATE-TIME:20221208T074000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3844@conference-indico.kek.jp
DESCRIPTION:Speakers: Mitsuhiro Nishida (Pohang University of Science and
Technology)\nKrylov complexity is a measure of operator growth that is con
sidered to capture quantum chaos in lattice systems. We study the Krylov c
omplexity and Lanczos coefficients of free scalar theories and their pertu
rbative theories in the continuum limit. In particular\, we discuss the ef
fects of mass\, hard UV cutoff\, thermal mass\, and perturbative interacti
ons.\n\nhttps://conference-indico.kek.jp/event/181/contributions/3844/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3844/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Curved domain-wall fermion and its anomaly inflow
DTSTART;VALUE=DATE-TIME:20221208T050000Z
DTEND;VALUE=DATE-TIME:20221208T052000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3837@conference-indico.kek.jp
DESCRIPTION:Speakers: Shoto Aoki (Osaka University)\nWe propose a lattice
fermion formulation with a curved domain-wall mass term as a nonperturbati
ve regularization of quantum field theory in a gravitational background
. In KEK-TH 2021 last year\, we reported that the edge-localized modes app
ear on the curved domain-wall in free fermion theory on a square lattice\,
and they feel gravity through the induced spin and spin-c connections. We
continue the study adding nontrivial $U(1)$ gauge field background to the
$S^1$ or $S^2$ domain-wall fermion systems. We find a good consistency wi
th continuum theory in the anomaly inflow described by the Atiyah-Patodi-S
inger index. This talk is based on our paper https://arxiv.org/abs/2203.03
782 and some preliminary results.\n\nhttps://conference-indico.kek.jp/even
t/181/contributions/3837/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3837/
END:VEVENT
BEGIN:VEVENT
SUMMARY:A microscopic description of the Witten effect with negatively mas
sive fermions
DTSTART;VALUE=DATE-TIME:20221208T052000Z
DTEND;VALUE=DATE-TIME:20221208T054000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3838@conference-indico.kek.jp
DESCRIPTION:Speakers: Hidenori Fukaya (Osaka University)\nInside topologic
al insulators or in the theta=pi vacuum\, magnetic monopoles gain fractio
nal electric charges\, which is known as the Witten effect. In this work\,
we try to give a microscopic description for this phenomenon\, solving a
"negatively" massive Dirac equation. The "Wilson term" plays a key role in
1) identifying the sign of the fermion mass\, 2) confirming evidence for
dynamical domain-wall creations\, and 3) understanding why the electric ch
arge is fractional.\n\nhttps://conference-indico.kek.jp/event/181/contribu
tions/3838/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3838/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Reality from maximizing overlap in the periodic complex action the
ory
DTSTART;VALUE=DATE-TIME:20221208T054000Z
DTEND;VALUE=DATE-TIME:20221208T060000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3839@conference-indico.kek.jp
DESCRIPTION:Speakers: Keiichi Nagao (Ibaraki University)\nWe study the per
iodic complex action theory (CAT) by imposing a periodic condition in the
future-included CAT where the time integration is performed from the past
to the future\, and extend a normalized matrix element of an operator O\,
which is called the weak value in the real action theory\, to another expr
ession. We present two theorems stating that the expression becomes real f
or O being Hermitian with regard to a modified inner product that makes a
given non-normal Hamiltonian H normal. The first theorem holds for a given
period $t_p$ in a case where the number of eigenstates having the maximal
imaginary part $B$ of the eigenvalues of H is just one\, while the second
one stands for $t_p$ selected such that the absolute value of the transit
ion amplitude is maximized in a case where $B \\leq 0$ and $|B|$ is much s
maller than the distances between any two real parts of the eigenvalues of
H. The latter proven via a number-theoretical argument suggests that\, if
our universe is periodic\, then even the period could be an adjustment pa
rameter to be determined in the Feynman path integral. This is a variant t
ype of the maximization principle that we previously proposed. This talk i
s based on the collaboration with Holger Bech Nielsen [Prog. Theor. Exp. P
hys. 2022 (9) 091B01] (arXiv:2203.07795 [quant-ph]).\n\nhttps://conference
-indico.kek.jp/event/181/contributions/3839/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3839/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Supersymmetric affine Toda field equations and ODE/IM corresponden
ce
DTSTART;VALUE=DATE-TIME:20221208T060000Z
DTEND;VALUE=DATE-TIME:20221208T062000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3840@conference-indico.kek.jp
DESCRIPTION:Speakers: Mingshuo Zhu (Tokyo Institute of Technology)\nThe li
near differential system of the $\\mathcal{N}=1$ super affine Toda field e
quations (ATFEs) (Classical) with Lie superalgebras is studied. The modifi
ed linear equations reduce to a couple of ordinary differential equations
(ODEs). The $osp(2|2)^{(2)}$ giving the Schrodinger equation with squared
potential verifies the ODE/IM correspondence.\n\nhttps://conference-indico
.kek.jp/event/181/contributions/3840/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3840/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Real-time evolution of quantum tunneling via the thimble approach
DTSTART;VALUE=DATE-TIME:20221208T064000Z
DTEND;VALUE=DATE-TIME:20221208T070000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3833@conference-indico.kek.jp
DESCRIPTION:Speakers: Atis Yosprakob (Niigata University)\nQuantum tunneli
ng has been playing an important role in various fields of theoretical phy
sics. So far\, the only way for us to gain insights into the mechanism is
to use the instanton method\, which is based on imaginary-time formalism.
However\, to study its dynamics\, it is essential to use real-time formali
sm\, whose path integral is highly oscillatory. Fortunately\, Picard-Lefsc
hetz theory can be used to make the integral converge\, enabling us to per
form the Monte Carlo simulation. In this work\, we apply the Monte Carlo s
imulation based on thimbles to study the real-time evolution of the tunnel
ing process. In particular\, we show that quantum tunneling can be charact
erized by the dominance of complex classical solutions in the $\\hbar\\rig
htarrow0$ limit.\n\nhttps://conference-indico.kek.jp/event/181/contributio
ns/3833/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3833/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Exact solution of the finite Grosse-Wulkenhaar model
DTSTART;VALUE=DATE-TIME:20221208T070000Z
DTEND;VALUE=DATE-TIME:20221208T072000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3834@conference-indico.kek.jp
DESCRIPTION:Speakers: Naoyuki Kanomata (Tokyo University of Science)\nWe f
ind the exact solutions of the $\\Phi_{2}^{3}$ finite matrix model (Grosse
-Wulkenhaar model). In the $\\Phi_{2}^{3}$ finite matrix model\, multipoin
t correlation functions are expressed as $G_{|a_{1}^{1}\\ldots a_{N_{1}}^{
1}|\\ldots|a_{1}^{B}\\ldots a_{N_{B}}^{B}|}$. The $\\sum_{i=1}^{B}N_{i}$-p
oint function denoted by $G_{|a_{1}^{1}\\ldots a_{N_{1}}^{1}|\\ldots|a_{1}
^{B}\\ldots a_{N_{B}}^{B}|}$ is given by the sum over all Feynman diagrams
(ribbon graphs) on Riemann surfaces with $B$-boundaries\, and each $|a^{i
}_{1}\\cdots a^{i}_{N_{i}}|$ corresponds to the Feynman diagrams having $N
_{i}$-external lines from the $i$-th boundary. It is known that any $G_{|a
_{1}^{1}\\ldots a_{N_{1}}^{1}|\\ldots|a_{1}^{B}\\ldots a_{N_{B}}^{B}|}$ ca
n be expressed using $G_{|a^{1}|\\ldots|a^{n}|}$ type $n$-point functions.
Thus we focus on rigorous calculations of $G_{|a^{1}|\\ldots|a^{n}|}$. Th
e formula for $G_{|a^{1}|\\ldots|a^{n}|}$ is obtained\, and it is achieved
by using the partition function $\\mathcal{Z}[J]$ calculated by the Haris
h-Chandra-Itzykson-Zuber integral.\n\nhttps://conference-indico.kek.jp/eve
nt/181/contributions/3834/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3834/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Nucleon D-term in holographic QCD
DTSTART;VALUE=DATE-TIME:20221208T072000Z
DTEND;VALUE=DATE-TIME:20221208T074000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3835@conference-indico.kek.jp
DESCRIPTION:Speakers: Mitsutoshi Fujita (Sun Yat-Sen University)\nThe D-te
rm is one of the conserved charges of hadrons defined as the forward limit
of the gravitational form factor D(t). We calculate the nucleon’s D-ter
m in a holographic QCD model in which the nucleon is described as a solito
n in five dimensions. We show that the form factor D(t) is saturated by th
e exchanges of infinitely many 0++ and 2++ glueballs dual to transverse-tr
aceless metric fluctuations on the Wick rotated AdS7 black hole geometry.
We refer to this phenomenon as ‘glueball dominance’\, in perfect an
alogy to the vector meson dominance of the electromagnetic form factors. H
owever\, the value at vanishing momentum transfer D(t = 0) can be interpre
ted as due to the exchange of pairs of pions and infinitely many vector an
d axial-vector mesons without any reference to glueballs. We find that the
D-term is slightly negative as a result of a cancellation between the iso
vector and isoscalar meson contributions.\n\nhttps://conference-indico.kek
.jp/event/181/contributions/3835/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3835/
END:VEVENT
BEGIN:VEVENT
SUMMARY:The emergence of (3+1)-dimensional space-time in the type IIB matr
ix model
DTSTART;VALUE=DATE-TIME:20221208T050000Z
DTEND;VALUE=DATE-TIME:20221208T052000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3829@conference-indico.kek.jp
DESCRIPTION:Speakers: Kohta Hatakeyama (KEK)\nWe perform numerical studies
of the type IIB matrix model\, which was proposed as a nonperturbative fo
rmulation of superstring theory in 1996. We overcome the sign problem by u
sing the complex Langevin method and show that it is necessary to add a te
rm corresponding to infrared regularization to the action of the original
model. By these procedures\, we find the (3+1)D expanding space-time in th
is model.\n\nhttps://conference-indico.kek.jp/event/181/contributions/3829
/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3829/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Bond-weighting method for the Grassmann tensor renormalization gro
up
DTSTART;VALUE=DATE-TIME:20221208T052000Z
DTEND;VALUE=DATE-TIME:20221208T054000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3830@conference-indico.kek.jp
DESCRIPTION:Speakers: Shinichiro Akiyama (The University of Tokyo)\nRecent
ly\, the tensor network description with bond weights on its edges has bee
n proposed as a novel improvement for the tensor renormalization group (TR
G). The bond weight is controlled by a single hyperparameter\, whose optim
al value is estimated in the original work via the numerical computation o
f the two-dimensional critical Ising model. We develop this bond-weighted
TRG algorithm to make it applicable to the fermionic system\, benchmarking
with the two-dimensional massless Wilson fermion. We show that the accura
cy with the fixed bond dimension is improved also in the fermionic system
and provide numerical evidence that the optimal choice of the hyperparamet
er is not affected by whether the system is bosonic or fermionic. In addit
ion\, by monitoring the singular value spectrum\, we find that the scale-i
nvariant structure of the renormalized Grassmann tensor is successfully ke
pt by the bond-weighting technique.\n\nhttps://conference-indico.kek.jp/ev
ent/181/contributions/3830/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3830/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Path Integral and Phase Space Dynamics of U(1) Quantum Pendulum
DTSTART;VALUE=DATE-TIME:20221208T054000Z
DTEND;VALUE=DATE-TIME:20221208T060000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3831@conference-indico.kek.jp
DESCRIPTION:Speakers: Tetsuo Matsui (Kindai University)\nWe study the time
dependent behavior of a quantum pendulum by path-integral and Wigner-Weyl
phase space quantum mechanics. In both cases\, we encounter a negative si
gn problem\, and propose certain approximation similar to the truncated Wi
gner approximation\, which sheds some light on the sign problem.\n\nhttps:
//conference-indico.kek.jp/event/181/contributions/3831/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3831/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Bounds on expectation values in Quantum mechanics
DTSTART;VALUE=DATE-TIME:20221208T060000Z
DTEND;VALUE=DATE-TIME:20221208T062000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3832@conference-indico.kek.jp
DESCRIPTION:Speakers: Takeshi Morita (Shizuoka University)\nThe range of m
otion of a particle with certain energy $E$ confined in a potential is det
ermined from the energy conservation law in classical mechanics. The count
erpart of this question in quantum mechanics can be thought of as what the
possible range of the expectation values of the position operator $⟨x
⟩$ of a particle\, which satisfies $E=⟨H⟩$. This range would change
depending on the state of the particle\, but the universal upper and lower
bounds\, which is independent of the state\, must exist. In this talk\, I
show that these bounds can be derived by using the uncertainty relations
and their generalization.\n\nhttps://conference-indico.kek.jp/event/181/co
ntributions/3832/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3832/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Numerical studies on the IKKT matrix model using Lefschetz thimble
method
DTSTART;VALUE=DATE-TIME:20221207T052000Z
DTEND;VALUE=DATE-TIME:20221207T054000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3823@conference-indico.kek.jp
DESCRIPTION:Speakers: Naoyuki Yamamori (SOKENDAI)\nThe IKKT matrix model i
s a candidate for the non-perturbative formalization of superstring the
ory in 10 dimension. This model suggests that the (9+1)-dimensional Lorent
z symmetry is spontaneously broken and (3+1)-dimensional space-time emerge
s. However\, the sign problem is the main obstacle to the numerical analys
is of this model. Recently\, numerical studies has been conducted by compl
ex Langevin method to overcome the sign problem\, but this method has cert
ain application limit. Therefore\, we performed\, for the first time\,
the calculation using another method\, Lefschetz thimble method\, which do
es not have such application limit.\n\nhttps://conference-indico.kek.jp/ev
ent/181/contributions/3823/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3823/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Analytical analysis of the bosonic Lorentzian IKKT matrix model wi
th a mass term
DTSTART;VALUE=DATE-TIME:20221207T054000Z
DTEND;VALUE=DATE-TIME:20221207T060000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3824@conference-indico.kek.jp
DESCRIPTION:Speakers: Worapat Piensuk (SOKENDAI)\nThe IKKT matrix model wa
s conjectured to provide a non-perturbative definition of the type IIB str
ing theory. One of the most attractive features of this model is that spac
etime emerges dynamically by interpreting the matrix degrees of freedom as
ten-dimensional spacetime coordinates. There have been many numerical sim
ulations suggesting the appearance of (3+1)-dimensional expanding universe
. In the recent work [1]\, it was shown that the spacetime arising from th
e bosonic version of the model is Euclidean and complex. To realize a real
Lorentzian spacetime\, an additional mass term was then introduced. In th
is work\, we investigate the bosonic Lorentzian IKKT matrix model with a m
ass term analytically. [1] K. Hatakeyama\, K. Anagnostopoulos\, T. Azum
a\, M. Hirasawa\, Y. Ito\, J. Nishimura\, S. K. Papadoudis\, and A. Tsuchi
ya\, Complex Langevin studies of the emergent space-time in the type IIB m
atrix model\, in East Asia Joint Symposium on Fields and Strings 2021\, 1\
, 2022. arXiv:2201.13200.\n\nhttps://conference-indico.kek.jp/event/181/co
ntributions/3824/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3824/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Fractional topological charge in lattice Abelian gauge theory
DTSTART;VALUE=DATE-TIME:20221207T060000Z
DTEND;VALUE=DATE-TIME:20221207T062000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3825@conference-indico.kek.jp
DESCRIPTION:Speakers: Motokazu Abe (Kyushu University)\nSince Gaiotto et.~
al discussed the low-energy dynamics of gauge theories on the basis of the
mixed ’t Hooft anomaly between discrete and higher-form symmetries\, th
is type of application of the anomaly has been studied vigorously. In this
study\, in order to understand this type of application of the anomaly in
a completely regularized framework\, we formulate the fractional topologi
cal charge associated with the $U(1)/\\mathbb{Z}_q$ principal bundle in th
e compact $U(1)$ lattice gauge theory by generalizing L\\“uscher’s con
struction. This fractional topological charge in lattice gauge theory is $
\\mathbb{Z}_q$ one-form gauge invariant and odd under the lattice time re
versal transformation. By employing these properties of the fractional top
ological charge\, we can show that the $U(1)$ gauge theory containing matt
er fields with charge $q\\in 2\\mathbb{Z}$ has the mixed ’t Hooft anomal
y between the $\\mathbb{Z}_q$ one-form symmetry and the time reversal symm
etry when $\\theta=\\pi$. This is analogous to the mixed ’t Hooft anomal
y between the $\\mathbb{Z}_N$ one-form symmetry and the time reversal symm
etry in $SU(N)/\\mathbb{Z}_N$ theory when $\\theta=\\pi$.\n\nhttps://confe
rence-indico.kek.jp/event/181/contributions/3825/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3825/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Phase structure of linear quiver gauge theories from anomaly match
ing
DTSTART;VALUE=DATE-TIME:20221207T062000Z
DTEND;VALUE=DATE-TIME:20221207T064000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3826@conference-indico.kek.jp
DESCRIPTION:Speakers: Hiroki Wada (Osaka University)\nWe consider the phas
e structure of the linear quiver gauge theory\, using the 't Hooft anomaly
matching condition. This theory is characterized by the length $K$ of the
quiver diagram. When $K$ is even\, the symmetry and its anomaly are the s
ame as those of massless QCD. Therefore\, one can expect that the spontane
ous symmetry breaking similar to the chiral symmetry breaking occurs. On t
he other hand\, when $K$ is odd\, the anomaly matching condition is satisf
ied by the massless composite fermions. We also consider the thermal parti
tion function under the twisted boundary conditions. When $K$ is even\, fr
om the anomaly at finite temperature\, we estimate the relation between th
e critical temperatures associated with the confinement/deconfinement and
the breaking of the global symmetry. Finally we discuss the anomaly matchi
ng at finite temperature when $K$ is odd.\n\nhttps://conference-indico.kek
.jp/event/181/contributions/3826/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3826/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Spontaneous CP breaking in 4D SU(N) gauge theory at $\\theta=\\pi$
and its restoration at finite temperature
DTSTART;VALUE=DATE-TIME:20221207T064000Z
DTEND;VALUE=DATE-TIME:20221207T070000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3827@conference-indico.kek.jp
DESCRIPTION:Speakers: Akira Matsumoto (RIKEN iTHEMS)\nRecent studies on th
e 't Hooft anomaly matching condition for 4D SU($N$) gauge theory have sug
gested that the phase structure at $\\theta=\\pi$ should be nontrivial.
Namely\, some symmetry will be spontaneously broken\, or gapless modes wi
ll appear. In the large-$N$ limit\, it is known that CP symmetry at $\\
theta=\\pi$ is broken in the confined phase\, while it restores in the
deconfined phase\, which is indeed one of the consequence of the anomaly m
atching. However\, at small $N$\, one may find a qualitatively differen
t phase structure\, which will be another possible scenario consistent wit
h the anomaly matching. Here we investigate this issue for $N=2$ by dir
ect lattice calculations. The crucial point of our method is that the r
estoration of CP symmetry can be probed by the sudden change of the topolo
gical charge distribution at $\\theta=0$\, which can be seen by simulat
ing the theory at imaginary $\\theta$ without the sign problem. Our res
ults suggest that the CP symmetry at $\\theta=\\pi$ is restored at higher
temperature than the deconfining temperature unlike the situation in the l
arge-$N$ limit.\n\nhttps://conference-indico.kek.jp/event/181/contribution
s/3827/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3827/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Optimized flow for generalized Lefschetz thimble method
DTSTART;VALUE=DATE-TIME:20221207T070000Z
DTEND;VALUE=DATE-TIME:20221207T072000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3828@conference-indico.kek.jp
DESCRIPTION:Speakers: Katsuta Sakai (Tokyo Medical and Dental University)\
nGeneralized thimble method is one of powerful methods to overcome the sig
n problem in numerical simulations. We point out that the method has a sub
tle property when applied to a nearly continuum system. The point is that
solutions of the flow equation generically show exponential behavior\, and
the growing rates largely differ depending on the modes. It implies t
he ranges of the flow time where we resolve the sign problem and the Ergod
icity problem are largely different mode by mode. It can leads to a great
inefficiency in the simulation\, in particular where we move the sampling
point on the original contour. In order to deal with the subtlety\, we pro
pose the modified flow equation which preserves the properties of the orig
inal one and nevertheless normalizes the growing rates. As a demonstration
\, we reproduce the real-time evolution of an anharmonic oscillator with t
he modified flow\, where it is difficult to perform the simulation with th
e original one.\n\nhttps://conference-indico.kek.jp/event/181/contribution
s/3828/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3828/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Unstable Nambu-Goldstone modes
DTSTART;VALUE=DATE-TIME:20221207T054000Z
DTEND;VALUE=DATE-TIME:20221207T060000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3819@conference-indico.kek.jp
DESCRIPTION:Speakers: Ryo Yokokura (KEK)\nNambu-Goldstone (NG) modes for 0
-form and higher-form symmetries can become unstable in the presence of ba
ckground fields. The examples include the instability of a photon with a t
ime-dependent axion background or with a chirality imbalance\, known as th
e chiral plasma instability\, and the instability of a dynamical axion wit
h a background electric field. We show that all these phenomena can be uni
versally described by a symmetry algebra for 0-form and higher-form symmet
ries. We prove a counting rule for the number of unstable NG modes in term
s of correlation functions of broken symmetry generators. Based on our uni
fied description\, we further give a simple new example where one of the N
G modes associated with the spontaneous 0-form symmetry breaking U(1) $\\t
imes$ U(1) $\\to$ 1 becomes unstable.\n\nhttps://conference-indico.kek.jp/
event/181/contributions/3819/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3819/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Formation of chiral soliton lattice
DTSTART;VALUE=DATE-TIME:20221207T060000Z
DTEND;VALUE=DATE-TIME:20221207T062000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3820@conference-indico.kek.jp
DESCRIPTION:Speakers: Kentaro Nishimura (KEK)\nThe Chiral Soliton Lattice
(CSL) is a lattice structure composed of domain walls aligned in parallel
at equal intervals\, which is energetically stable in the presence of a ba
ckground magnetic field and a finite (baryon) chemical potential due to th
e topological term originated from the chiral anomaly. We study its format
ion from the vacuum state\, with describing the CSL as a layer of domain-w
all disks surrounded by the vortex or string loop\, based on the Nambu-Got
o-type effective theory. We show that the domain wall nucleates via quantu
m tunneling when the magnetic field is strong enough. We evaluate its nucl
eation rate and determine the critical magnetic field strength with which
the nucleation rate is no longer exponentially suppressed. We apply this a
nalysis to the neutral pion in the two-flavor QCD as well as the axion-lik
e particles (ALPs) with a finite (baryon) chemical potential under an exte
rnal magnetic field. In the former case\, even though the CSL state is mor
e energetically stable than the vacuum state and the nucleation rate becom
es larger for sufficiently strong magnetic field\, it cannot be large enou
gh so that the nucleation of the domain walls is not exponentially suppres
sed and promoted\, without suffering from the tachyonic instability of the
charged pion fluctuations. In the latter case\, we confirm that the effec
tive interaction of the ALPs generically includes the topological term req
uired for the CSL state to be energetically favored. We show that the ALP
CSL formation is promoted if the magnetic field strength and the chemical
potential of the system is slightly larger than the scale of the axion dec
ay constant.\n\nhttps://conference-indico.kek.jp/event/181/contributions/3
820/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3820/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Boson-fermion duality with subsystem symmetry
DTSTART;VALUE=DATE-TIME:20221207T062000Z
DTEND;VALUE=DATE-TIME:20221207T064000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3821@conference-indico.kek.jp
DESCRIPTION:Speakers: Weiguang Cao (Kavli IPMU\, University of Tokyo)\nIn
this talk\, I will introduce an exact duality in (2 + 1)d between the ferm
ionization of a bosonic theory with a $Z_2$ subsystem symmetry and a fermi
onic theory with a $Z_2$ subsystem fermion parity symmetry. A typical exam
ple is the duality between the fermionization of the plaquette Ising model
and the plaquette fermion model. I will establish the exact duality on t
he lattice by using the generalized Jordan-Wigner map\, with a careful dis
cussion on the mapping of the twist and symmetry sectors. This motivates u
s to introduce the subsystem Arf invariant\, which exhibits a foliation st
ructure.\n\nhttps://conference-indico.kek.jp/event/181/contributions/3821/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3821/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Scalar\, fermionic and supersymmetric field theories with subsyste
m symmetries
DTSTART;VALUE=DATE-TIME:20221207T064000Z
DTEND;VALUE=DATE-TIME:20221207T070000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3822@conference-indico.kek.jp
DESCRIPTION:Speakers: Taiichi Nakanishi (YITP\, Kyoto Univ.)\nIt is known
that the field-theoretic model describing fractons\, which have attracted
much attention in condensed matter physics\, is a theory with non-Lorentz
covariant symmetry\, called subsystem symmetry. More recently\, a fermioni
c field theory that seems to be related to fractons has been constructed.
In this presentation\, we discuss detailed properties of these field theor
ies.\n\nhttps://conference-indico.kek.jp/event/181/contributions/3822/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3822/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Solitonic symmetry beyond homotopy: invertibility from bordism and
non-invertibility from TQFT
DTSTART;VALUE=DATE-TIME:20221207T052000Z
DTEND;VALUE=DATE-TIME:20221207T054000Z
DTSTAMP;VALUE=DATE-TIME:20230929T143311Z
UID:indico-contribution-181-3818@conference-indico.kek.jp
DESCRIPTION:Speakers: Shi Chen (The University of Tokyo)\nSolitonic symmet
ry is believed to follow the homotopy-group classification of topological
solitons. Here\, we point out a more sophisticated algebraic structure whe
n solitons of different codimensions coexist in the spectrum. We uncover t
his phenomenon in a concrete quantum field theory\, the $4$d $\\mathbb{C}P
^1$ model. This model has two kinds of solitonic excitations\, vortices an
d hopfions\, which would follow two $U(1)$ solitonic symmetries according
to homotopy groups. Nevertheless\, we demonstrate the nonexistence of t
he hopfion $U(1)$ symmetry by evaluating the hopfion charge of vortex oper
ators. We clarify that what conserves hopfion numbers is a non-invertible
symmetry generated by 3d spin topological quantum field theories (TQFTs).
Its invertible subgroup is just $\\mathbb{Z}_2$\, which we recognize as a
spin bordism invariant. Compared with the 3d $\\mathbb{C}P^1$ model\, our
work suggests a unified description of solitonic symmetries and couplings
to topological phases.\n\nhttps://conference-indico.kek.jp/event/181/contr
ibutions/3818/
LOCATION:Online (Zoom)
URL:https://conference-indico.kek.jp/event/181/contributions/3818/
END:VEVENT
END:VCALENDAR