Article
Physics, Particles & Fields
Masamichi Miyaji, Tadashi Takayanagi, Tomonori Ugajin
Summary: The study investigates overlaps between regularized boundary states in conformal field theories using AdS/BCFT duality, finding that the overlaps are exponentially suppressed and h_(ab)^(min) = c/24 in pure AdS3 gravity. In higher dimensions, h_(ab)^(min) depends on the tensions of the branes. The off diagonal elements of inner products in holographic boundary states can be computed directly from on-shell gravity actions.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Jan Boruch, Pawel Caputa, Dongsheng Ge, Tadashi Takayanagi
Summary: This work elaborates on the holographic description of path-integral optimization using Hartle-Hawking wave functions in Anti-de Sitter spacetimes in conformal field theories. It argues that maximizing the Hartle-Hawking wave function is equivalent to the path-integral optimization procedure in CFT. The study shows that metrics maximizing gravity wave functions in particular holographic geometries precisely match those derived in the path-integral optimization procedure for their dual CFT states.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Hardik Bohra, Ashish Kakkar, Allic Sivaramakrishnan
Summary: This paper explores perturbative corrections to quantum information geometry, focusing on the Bures information metric associated with correlation functions of a conformal field theory. The metric of holographic four-point functions is computed, with corrections generated by tree Witten diagrams in the bulk included. The properties of correlators are translated into the language of information geometry in this setting. The cross terms in the information metric encode non-identity operators in the operator product expansion (OPE), and it is found that the information metric is asymptotically AdS. Additionally, an information metric for transition amplitudes is discussed.
JOURNAL OF HIGH ENERGY PHYSICS
(2022)
Article
Physics, Particles & Fields
Pawel Caputa, Jorrit Kruthoff, Onkar Parrikar
Summary: In this paper, we discuss a novel family of Euclidean path integral states in two-dimensional holographic conformal field theories, which can be interpreted as continuous tensor network (CTN) states. These CTN states satisfy a Ryu-Takayanagi-like minimal area upper bound on entanglement entropies, with a coefficient of 14GN. The original state of the CFT can be expressed as a superposition of such CTN states, with the corresponding wavefunction being the bulk Hartle-Hawking wavefunction.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Saba Asif Baig, Andreas Karch
Summary: In contrast to traditional field theory defects, a double brane holographic model allows for a range of accessible transmission coefficients for a fixed value of log g.
JOURNAL OF HIGH ENERGY PHYSICS
(2022)
Article
Physics, Particles & Fields
Nejc Ceplak, Stefano Giusto, Marcel R. R. Hughes, Rodolfo Russo
Summary: The connected tree-level part of 4-point holographic correlators in AdS(3) x S-3 x M involving multi-trace and single-trace operators were derived. These correlators were found to be compactly written in terms of Bloch-Wigner-Ramakrishnan functions for multi-trace operators. Consistency checks were performed on the derived expressions and anomalous dimensions of non-BPS double-trace operators were extracted.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Nima Afkhami-Jeddi, Henry Cohn, Thomas Hartman, Amirhossein Tajdini
Summary: The study focuses on the torus partition functions of free bosonic CFTs in two dimensions, showing that integrating over Narain moduli defines an ensemble-averaged free CFT and the averaged partition function can be reinterpreted as a sum over topologies in three dimensions. This leads to the conjecture that an averaged free CFT in two dimensions is holographically dual to an exotic theory of three-dimensional gravity with U(1)(c)xU(1)(c) symmetry and a composite boundary graviton. Additionally, general constraints on the spectral gap of free CFTs are obtained for small central charge c, Narain compactifications with a large gap are constructed, and an analytic bootstrap functional corresponding to a single self-dual boson is found using the spinning modular bootstrap.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Krai Cheamsawat, Sebastian Fischetti, Lucas Wallis, Toby Wiseman
Summary: The behavior of the vacuum free energy of various (2+1)-dimensional CFTs on an ultrastatic spacetime as a function of spatial geometry was compared, showing qualitative similarity between the free theories and a remarkable quantitative similarity between holographic CFT and the free fermion. The holographic CFT, despite being strongly-coupled, differs from the fermion by less than one percent over a wide range of deformations.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Review
Physics, Multidisciplinary
Henriette Elvang
Summary: This article introduces two highly active research programs, conformal Bootstrap and scattering amplitudes, focusing on the common ideas and methods shared by these two programs, and exploring the possibility of consistent quantum field theories.
REPORTS ON PROGRESS IN PHYSICS
(2021)
Article
Physics, Particles & Fields
Anatoly Konechny
Summary: In this paper, the authors study RG interfaces for boundary RG flows in two-dimensional QFTs and put forward several conjectures regarding their general properties. These conjectures are supported by perturbative calculations, a variational method, and numerical results. Some of the considerations can be generalized to bulk flows, clarifying conceptual issues related to the RG interface.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Andreas Karch, Zhu-Xi Luo, Hao-Yu Sun
Summary: This study explores entanglement entropy in 1+1 dimensional conformal field theories with interfaces from a holographic perspective, revealing that the location of the interface can affect the entanglement entropy, showing new patterns and universal relationships.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Multidisciplinary
Anatoly Konechny
Summary: In this study, a two-dimensional Ising field theory with a piecewise constant boundary magnetic field is considered, showing that the model can be described by a quadratic Lagrangian in the case where the magnetic field takes only two different values of the same magnitude but with different signs. The exact reflection matrix for this model is calculated and analyzed, along with the boundary entropy and space of RG flows in a three-parameter space with four different infrared fixed points. Discussions are provided regarding the breakdown of integrability in an extended model allowing for two generic values of the boundary magnetic field.
JOURNAL OF PHYSICS A-MATHEMATICAL AND THEORETICAL
(2022)
Article
Physics, Particles & Fields
Christopher P. Herzog, Abhay Shrestha
Summary: This paper introduces a practical tool for investigating two-point correlation functions in defect conformal field theory and provides an alternative method for dealing with complex tensor situations. The paper also includes examples and analyzes constraints arising from conservation and equations of motion.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Hare Krishna, D. Rodriguez-Gomez
Summary: In this study, 2-point correlation functions for scalar operators in position space are examined using holography, with a focus on operators with large conformal dimensions. The geodesic approximation is utilized for propagators. In addition to the main contribution, a correction involving bulk cubic couplings and higher curvature couplings is identified, which provides insight into the interior of a black hole.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Review
Physics, Multidisciplinary
Shai M. Chester
Summary: These lectures aim to familiarize students with the nuts and bolts of numerical bootstrap in an efficient manner, covering the basics of conformal field theory, computation of conformal blocks, formulation of crossing equations as a semi-definite programming problem, solving the problem using SDPB, and interpretation of the results. The lectures include worked examples and problem sets to help students master the skills, culminating in a precise computation of the critical exponents of the 3d Ising model.
PHYSICS REPORTS-REVIEW SECTION OF PHYSICS LETTERS
(2023)
Article
Physics, Particles & Fields
Tadashi Takayanagi, Takahiro Uetoko
Summary: In this paper, a Chern-Simons gravity dual of a two dimensional conformal field theory on a manifold with boundaries, known as boundary conformal field theory (BCFT), is provided. The correct boundary action on the end of the world brane in the Chern-Simons gauge theory is determined, reproducing known results of the AdS/BCFT for the Einstein gravity. A prescription for calculating holographic entanglement entropy using Wilson lines extending from the AdS boundary to the end of the world brane is given, and a higher spin extension of the formulation is discussed.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Tatsuma Nishioka, Tadashi Takayanagi, Yusuke Taki
Summary: The paper introduces the concept of topological pseudo entropy and examines its applications in Chern-Simons gauge theory. It demonstrates the equivalence between topological pseudo entropy and interface entropy, and also finds that the topological interface entropy for rational CFTs has a contribution identical to the topological entanglement entropy on a torus.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Jan Boruch, Pawel Caputa, Dongsheng Ge, Tadashi Takayanagi
Summary: This work elaborates on the holographic description of path-integral optimization using Hartle-Hawking wave functions in Anti-de Sitter spacetimes in conformal field theories. It argues that maximizing the Hartle-Hawking wave function is equivalent to the path-integral optimization procedure in CFT. The study shows that metrics maximizing gravity wave functions in particular holographic geometries precisely match those derived in the path-integral optimization procedure for their dual CFT states.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Masamichi Miyaji, Tadashi Takayanagi, Tomonori Ugajin
Summary: The study investigates overlaps between regularized boundary states in conformal field theories using AdS/BCFT duality, finding that the overlaps are exponentially suppressed and h_(ab)^(min) = c/24 in pure AdS3 gravity. In higher dimensions, h_(ab)^(min) depends on the tensions of the branes. The off diagonal elements of inner products in holographic boundary states can be computed directly from on-shell gravity actions.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Astronomy & Astrophysics
Ibrahim Akal, Yuya Kusuki, Noburo Shiba, Tadashi Takayanagi, Zixia Wei
Summary: This paper extensively studies moving mirrors in conformal field theories using field theoretic and holographic methods, focusing on escaping, kink, and double escaping mirror models. The holographic entanglement entropy calculations show the ideal Page curve in the kink mirror model and an interesting phase transition in the double escaping mirror model. Discussions also include the interpretation of moving mirrors in terms of two dimensional Liouville gravity and the connection between quantum energy conditions and the time evolution of holographic entanglement entropy.
CLASSICAL AND QUANTUM GRAVITY
(2021)
Article
Physics, Particles & Fields
Kenta Suzuki, Tadashi Takayanagi
Summary: In this paper, the connection between Jackiw-Teitelboim (JT) gravity on two-dimensional anti de-Sitter spaces and a semiclassical limit of c < 1 two-dimensional string theory is studied. Through world-sheet theory and matrix model methods, the correspondence between different theories is demonstrated.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Taishi Kawamoto, Takato Mori, Yu-ki Suzuki, Tadashi Takayanagi, Tomonori Ugajin
Summary: We present a gravity dual model for local operator quench in a two-dimensional CFT with conformal boundaries. The model consists of a massive excitation in a three-dimensional AdS space and an end of the world brane, which undergoes nontrivial deformations due to gravitational backreaction. We show that the energy-momentum tensor and entanglement entropy computed from the gravity dual and from the BCFT in the large c limit perfectly match, elegantly avoiding the folding of the end of the world brane.
JOURNAL OF HIGH ENERGY PHYSICS
(2022)
Article
Physics, Particles & Fields
Yasuaki Hikida, Tatsuma Nishioka, Tadashi Takayanagi, Yusuke Taki
Summary: We present a class of dS/CFT correspondence between two-dimensional CFTs and three-dimensional de Sitter spaces. We argue that this correspondence includes various gravity limits and dualities associated with SU(2) and SU(N) WZW models. We confirm the correctness of this correspondence and study two-point functions and entanglement entropy. We also discuss the possible spectrum and quantum corrections in the gravity theory.
JOURNAL OF HIGH ENERGY PHYSICS
(2022)
Article
Physics, Multidisciplinary
Yasuaki Hikida, Tatsuma Nishioka, Tadashi Takayanagi, Yusuke Taki
Summary: This letter proposes a holographic duality for classical gravity on a three-dimensional de Sitter space and presents evidence in terms of classical partition function and conformal field theory.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Particles & Fields
Kenta Suzuki, Tadashi Takayanagi
Summary: In this paper, we investigate the equivalence between a boundary conformal field theory (BCFT) and a gravitational system by studying its duality relation in a two-dimensional setup. By examining the computation of entanglement entropy and energy flux conservation, we identify the dual two-dimensional gravity to the boundary dynamics of a BCFT. Furthermore, we demonstrate that one point functions can be correctly reproduced in the AdS/BCFT by considering a gravity solution with scalar fields turned on.
JOURNAL OF HIGH ENERGY PHYSICS
(2022)
Article
Physics, Particles & Fields
Hiroki Kanda, Masahide Sato, Yu-ki Suzuki, Tadashi Takayanagi, Zixia Wei
Summary: In this paper, we investigate the dynamics of EOW branes in AdS using scalar fields, which provide a new gravity dual for CFTs on manifolds with boundaries. We find explicit solutions that correspond to boundary RG flows, as well as annulus-like or cone-like shaped EOW branes that require the presence of the scalar field. Moreover, we present a gravity dual for a CFT on a strip with different boundary conditions due to the scalar potential, resulting in a confinement/deconfinement-like transition depending on temperature and the scalar potential. Finally, we highlight the close relationship between this phase transition and the measurement-induced phase transition via a Wick rotation.
JOURNAL OF HIGH ENERGY PHYSICS
(2023)
Article
Astronomy & Astrophysics
Ibrahim Akal, Taishi Kawamoto, Shan-Ming Ruan, Tadashi Takayanagi, Zixia Wei
Summary: The black hole singularity is crucial for understanding Hawking's information paradox. By imposing a final state boundary condition on the spacelike singularity, the conflict between global spacetime analysis and unitarity can potentially be resolved. Inspired by the final state proposal, this study explores the impact of final state projection in two dimensional conformal field theories. The researchers calculate the time evolution under postselection and use the real part of pseudoentropy to estimate the average amount of quantum entanglement between the initial and final states. The results show a Page-curve-like behavior for this quantity.
Article
Physics, Multidisciplinary
Hugo A. Camargo, Lucas Hackl, Michal P. Heller, Alexander Jahn, Tadashi Takayanagi, Bennet Windt
Summary: This article analyzes the quantities for two intervals in the vacuum of free bosonic and Ising conformal field theories using the most general Gaussian purifications, providing a comprehensive comparison with existing results and identifying universal properties. It further discusses important subtleties in the setup, such as the massless limit of the free bosonic theory and the Hilbert space structure under the Jordan-Wigner mapping in the spin chain model of the Ising conformal field theory.
PHYSICAL REVIEW RESEARCH
(2021)
Article
Astronomy & Astrophysics
Jan Boruch, Pawel Caputa, Tadashi Takayanagi
Summary: This paper introduces a gravity dual description of path integral optimization in conformal field theories and discusses the equivalence between maximizing the Hartle-Hawking wave function and the path integral optimization procedure, as well as its application in various dimensions.
Article
Astronomy & Astrophysics
Yoshifumi Nakata, Tadashi Takayanagi, Yusuke Taki, Kotaro Tamaoka, Zixia Wei
Summary: A new quantity called pseudo-entropy is introduced in this paper as a generalization of entanglement entropy via postselection, with potential applications as order parameters in quantum many-body systems. The geometric computation of pseudo-entropy in the AdS/CFT correspondence is explored, along with its properties and classifications in qubit systems. Additionally, the quantum information theoretic meaning of pseudo-entropy in specific examples is discussed, as well as its calculation in various scenarios including the presence of local operator excitations in different CFT models.
