Article
Physics, Particles & Fields
Christopher P. Herzog, Itamar Shamir
Summary: This study delves into the two point functions of marginal operators with the stress tensor and displacement operator in three dimensions, revealing the boundary anomaly and confirming agreement with the anomaly effective action. It also presents the anomaly effective action linking the Euler density term to the one point function anomaly for a higher dimensional conformal field theory with a four dimensional defect, extending previous results for two dimensional defects.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Christopher P. Herzog, Vladimir Schaub
Summary: In the context of boundary conformal field theory, a sum rule is derived that relates the two and three point functions of the displacement operator. For four dimensional conformal field theory with a three-dimensional boundary, this sum rule further relates the two boundary contributions to the anomaly in the trace of the stress tensor.
JOURNAL OF HIGH ENERGY PHYSICS
(2022)
Article
Physics, Particles & Fields
Yifan Wang
Summary: This paper studies the universal behaviors of a CFT in the presence of defects, proving that the defect a-anomaly must decrease under unitary defect RG flows and deriving the relation between the defect a- and c-anomalies and the U(1)(R) symmetry anomalies. The methods are illustrated with examples and the potential collider bounds on defect anomalies are discussed.
JOURNAL OF HIGH ENERGY PHYSICS
(2022)
Article
Physics, Particles & Fields
Yifan Wang
Summary: This study investigates new types of anomalies in conformal field theories with surface defects. By explicitly deriving and analyzing the scalar theory under defect RG flow, the b-theorem and a universal relation between the b-anomaly and U(1)(r) symmetry's 't Hooft anomaly are confirmed. Additionally, the b-extremization principle is established as a powerful tool for extracting the b-anomaly of strongly coupled surface defects.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Lorenzo Bianchi, Adam Chalabi, Vladimir Prochazka, Brandon Robinson, Jacopo Sisti
Summary: We study co-dimension two monodromy defects in theories of conformally coupled scalars and free Dirac fermions in arbitrary d dimensions, characterizing them through various correlation functions and anomaly coefficients. By calculating the universal contributions to entanglement entropy, we verify the values of defect central charges and extract universal parts of Renyi entropy. Additionally, we identify relevant deformations in singular defect theories and explore the renormalization group flow towards an IR fixed point. Finally, we analyze Gukov-Witten defects in free d = 4 Maxwell theory and show their central charges vanish.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Adam Chalabi, Christopher P. Herzog, Andy O'Bannon, Brandon Robinson, Jacopo Sisti
Summary: Motivated by quantum information and classification of quantum field theories, this study examines Conformal Field Theories (CFTs) in spacetime dimension d >= 5 with conformally-invariant spatial boundaries (BCFTs) or 4-dimensional conformal defects (DCFTs). The boundary or defect contributions to the Weyl anomaly are determined using a standard algorithm, and the central charges characterizing the BCFTs or DCFTs are calculated. In addition, several parity-even and parity-odd terms are discovered, and the impact of the parity-even central charges on physical observables are demonstrated.
JOURNAL OF HIGH ENERGY PHYSICS
(2022)
Article
Physics, Particles & Fields
Yoshiki Sato
Summary: We studied the p-dimensional conformal defect of a free Dirac fermion on a d-dimensional flat space and found important properties regarding boundary conditions. For a two-codimensional defect, a double trace deformation triggers a renormalization group flow from the Neumann boundary condition to the Dirichlet boundary condition, with the free energy at the UV fixed point always larger than that at the IR fixed point.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
A. V. Ivanov, D. V. Vassilevich
Summary: This study investigates the eta-invariant of a Dirac operator with local boundary conditions using heat kernel methods. In even dimensions, it is related to the eta-invariant of a boundary Dirac operator, while in odd dimensions, it is expressed through the index of boundary operators. The strong ellipticity condition is found to be necessary for the applicability of these methods, and it is shown that the Witten-Yonekura boundary conditions are not strongly elliptic.
JOURNAL OF HIGH ENERGY PHYSICS
(2022)
Article
Physics, Particles & Fields
Daniel G. Robbins, Eric Sharpe, Thomas Vandermeulen
Summary: This paper introduces a new set of modular-invariant phase factors for orbifolds, which can be used in orbifold calculations. After describing their basic properties, the authors generalize these phase factors to different orbifolds and propose a precise suggestion on how to make these orbifolds equivalent to disjoint unions of other orbifolds. This proposal is validated in numerous examples.
JOURNAL OF HIGH ENERGY PHYSICS
(2022)
Article
Physics, Particles & Fields
Shinji Hirano, Tatsuki Nakajima, Masaki Shigemori
Summary: In this study, stress-tensor correlators in TT-deformed conformal field theories in two dimensions were investigated using a geometrical method. The results reveal a logarithmic correction in the TT-deformed stress-tensor correlators, which is absent in lower-order functions but appears in the four-point function.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Tatsuma Nishioka, Yoshiki Sato
Summary: The study describes conformal defects of p dimensions in a free scalar theory as boundary conditions on the conformally flat space H(p+1)x?(d-p-1), classifying them into Dirichlet type and Neumann type. It is found that Dirichlet boundary conditions always exist, while Neumann boundary conditions are only allowed for defects of lower codimensions. The results are consistent with a recent classification of non-monodromy defects, highlighting the association of Neumann boundary conditions with non-trivial defects.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
R. Aros, F. Bugini, D. E. Diaz
Summary: This work continues the study of one-loop partition function for higher derivative conformal higher spin fields in six dimensions and its holographic counterpart in seven dimensions. By considering specific boundary conditions and heat kernel coefficients, the authors were able to match UV and IR divergences and obtain independent anomaly coefficients. Further investigation into non Ricci-flat Einstein boundaries revealed a discrepancy in computations for spins higher than two.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Teresa Bautista, Lorenzo Casarin, Hadi Godazgar
Summary: Motivated by the goal of applying the average null energy condition (ANEC) to renormalisation group flows, this research calculates the expectation value of the ANEC operator in a particular scalar state perturbatively in lambda phi (4) theory, up to third order in the quartic coupling. The study verifies the expected CFT answer and provides technical tools for studying the expectation value of the ANEC operator in more interesting states, such as tensorial states relevant to the Hofman-Maldacena collider bounds.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Nadav Drukker, Malte Probst, Maxime Trepanier
Summary: The article investigates the relation between the 2-point function of the displacement operator and the expectation value of the bulk stress tensor, translating it into a constraint on the anomaly coefficients associated with the defect. It also studies the defect operator expansion of the stress tensor multiplet and identifies several new operators of the defect CFT along the way. Some technical results derived include the explicit supersymmetry transformations of the stress tensor multiplet and the classification of unitary representations of the superconformal algebra preserved by the defect.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Francesco Alessio, Glenn Barnich, Martin Bonte
Summary: The study calculates the partition function of a massless scalar field on a Euclidean spacetime manifold and discusses the generalization of high/low temperature duality, as well as the modular covariance of the partition function under different geometric conditions. The results provided by the study offer valuable insights into the properties of quantum field theory in specific backgrounds.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Rajesh Kumar Gupta, Christopher P. Herzog, Imtak Jeon
JOURNAL OF HIGH ENERGY PHYSICS
(2020)
Article
Physics, Particles & Fields
Christopher P. Herzog, Nozomu Kobayashi
JOURNAL OF HIGH ENERGY PHYSICS
(2020)
Article
Physics, Particles & Fields
Christopher P. Herzog, Kuo-Wei Huang, Dmitri V. Vassilevich
JOURNAL OF HIGH ENERGY PHYSICS
(2020)
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
Christopher P. Herzog, Itamar Shamir
Summary: This study delves into the two point functions of marginal operators with the stress tensor and displacement operator in three dimensions, revealing the boundary anomaly and confirming agreement with the anomaly effective action. It also presents the anomaly effective action linking the Euler density term to the one point function anomaly for a higher dimensional conformal field theory with a four dimensional defect, extending previous results for two dimensional defects.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Christopher P. Herzog, Vladimir Schaub
Summary: In the context of boundary conformal field theory, a sum rule is derived that relates the two and three point functions of the displacement operator. For four dimensional conformal field theory with a three-dimensional boundary, this sum rule further relates the two boundary contributions to the anomaly in the trace of the stress tensor.
JOURNAL OF HIGH ENERGY PHYSICS
(2022)
Article
Physics, Particles & Fields
Adam Chalabi, Christopher P. Herzog, Andy O'Bannon, Brandon Robinson, Jacopo Sisti
Summary: Motivated by quantum information and classification of quantum field theories, this study examines Conformal Field Theories (CFTs) in spacetime dimension d >= 5 with conformally-invariant spatial boundaries (BCFTs) or 4-dimensional conformal defects (DCFTs). The boundary or defect contributions to the Weyl anomaly are determined using a standard algorithm, and the central charges characterizing the BCFTs or DCFTs are calculated. In addition, several parity-even and parity-odd terms are discovered, and the impact of the parity-even central charges on physical observables are demonstrated.
JOURNAL OF HIGH ENERGY PHYSICS
(2022)
Article
Physics, Particles & Fields
Christopher P. Herzog, Abhay Shrestha
Summary: In this paper, we consider a free Maxwell field in four dimensions in the presence of a codimension two defect. We find that only generalized free fields can appear in the defect operator product expansion of the bulk Maxwell field, and the correlation functions of these defect operators can be evaluated using Wick's Theorem.
JOURNAL OF HIGH ENERGY PHYSICS
(2022)
Article
Physics, Particles & Fields
Kuo-Wei Huang
Summary: By studying d = 4 conformal field theories with a pure Einstein gravity dual, we have discovered interesting results about algebraic structures. Under certain conditions, a rescaled mode operator satisfies a Virasoro algebra, and the structure is enhanced to a Kac-Moody algebra when additional components are incorporated.
JOURNAL OF HIGH ENERGY PHYSICS
(2022)
Article
Physics, Particles & Fields
Kuo-Wei Huang, Robin Karlsson, Andrei Parnachev, Samuel Valach
Summary: Averaged Null Energy Conditions (ANECs) hold in unitary quantum field theories. In conformal field theories, ANECs in states created by the application of the stress tensor to the vacuum lead to three constraints on the stress-tensor three-point couplings, depending on the choice of polarization. The same constraints can be derived from considering two-point functions of the stress tensor in a thermal state and focusing on the contribution of the stress tensor in the operator product expansion (OPE). In holographic Gauss-Bonnet gravity, ANEC saturation coincides with superluminal signal propagation in thermal states.
JOURNAL OF HIGH ENERGY PHYSICS
(2023)
Article
Physics, Particles & Fields
Chantelle Esper, Kuo-Wei Huang, Robin Karlsson, Andrei Parnachev, Samuel Valach
Summary: We consider thermal stress-tensor two-point functions in holographic theories and use the operator product expansion (OPE) to analyze them in the near-lightcone regime. We find that these correlators can be described by three universal functions, which can be computed holographically in Einstein gravity.
JOURNAL OF HIGH ENERGY PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
Vir B. Bulchandani, Benjamin Hsu, Christopher P. Herzog, S. L. Sondhi
Summary: Quantum spin liquids are topological states of matter that emerge in frustrated quantum magnets at low temperatures, exhibiting emergent gauge fields and fractionalized quasiparticles, with enhanced global symmetries. The study shows that the emergent gauge and symmetry structure in spin liquids result in a variety of additional hydrodynamic modes compared to high-temperature paramagnetic phases. A hydrodynamic regime for the internal U(1) gauge field common to both states is identified, characterized by slow diffusion of the internal transverse photon.
Article
Astronomy & Astrophysics
Kuo-Wei Huang
Summary: In this study, the operator product expansion of stress tensors in conformal field theories with a bulk dual of Einstein gravity in d > 2 dimensions was investigated. An algebraic structure consistent with the Jacobi identity was obtained from the TT OPE in a certain null-like limit, with a dimensionless constant C proportional to the central charge. Transverse integrals play a crucial role in the definition of L-m, and a connection between near-lightcone stress-tensor conformal block in d > 2 dimensions and the d = 2W algebra was observed.
Article
Physics, Particles & Fields
A. Liam Fitzpatrick, Kuo-Wei Huang, David Meltzer, Eric Perlmutter, David Simmons-Duffin
JOURNAL OF HIGH ENERGY PHYSICS
(2020)
Article
Astronomy & Astrophysics
Kuo-Wei Huang