ENTANGLEMENT ENTROPY AND QUANTUM FIELD THEORY: A NON-TECHNICAL INTRODUCTION

We give a pedagogical and non-technical introduction to the quantum field theory approach to entanglement entropy. Particular attention is devoted to the one space dimensional case, with a linear dispersion relation, that, at a quantum critical point, can be effectively described by a two-dimensional conformal field theory.

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A Review of Conformal Field Theory in 2D

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v6i2.1784 ◽

2014 ◽

Vol 6 (2) ◽

pp. 1079-1105

Author(s):

Rahul Nigam

Keyword(s):

Field Theory ◽

Quantum Field Theory ◽

Conformal Field Theory ◽

Statistical Mechanics ◽

Critical Behavior ◽

Verma Module ◽

Virasoro Algebra ◽

Quantum Field ◽

Conformal Field ◽

Insight Into

In this review we study the elementary structure of Conformal Field Theory in which is a recipe for further studies of critical behavior of various systems in statistical mechanics and quantum field theory. We briefly review CFT in dimensions which plays a prominent role for example in the well-known duality AdS/CFT in string theory where the CFT lives on the AdS boundary. We also describe the mapping of the theory from the cylinder to a complex plane which will help us gain an insight into the process of radial quantization and radial ordering. Finally we will develop the representation of the Virasoro algebra which is the well-known "Verma module".Â Â

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ON THE QUANTUM THEORY OF MASSLESS SPIN-3/2 FIELD IN MINKOWSKI SPACETIME

International Journal of Geometric Methods in Modern Physics ◽

10.1142/s0219887806001697 ◽

2006 ◽

Vol 03 (07) ◽

pp. 1303-1312 ◽

Cited By ~ 1

Author(s):

WEIGANG QIU ◽

FEI SUN ◽

HONGBAO ZHANG

Keyword(s):

Field Theory ◽

Quantum Field Theory ◽

Quantum Theory ◽

Casimir Effect ◽

Minkowski Spacetime ◽

Quantum Field ◽

Explicit Result ◽

Massless Spin ◽

The Many ◽

The One

From the modern viewpoint and by the geometric method, this paper provides a concise foundation for the quantum theory of massless spin-3/2 field in Minkowski spacetime, which includes both the one-particle's quantum mechanics and the many-particle's quantum field theory. The explicit result presented here is useful for the investigation of spin-3/2 field in various circumstances such as supergravity, twistor programme, Casimir effect, and quantum inequality.

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Null Wave Front and Ryu–Takayanagi Surface

Entropy ◽

10.3390/e22111297 ◽

2020 ◽

Vol 22 (11) ◽

pp. 1297

Author(s):

Jun Tsujimura ◽

Yasusada Nambu

Keyword(s):

Field Theory ◽

Quantum Field Theory ◽

Cosmological Constant ◽

Minimal Surface ◽

Wave Front ◽

Entanglement Entropy ◽

Necessary Condition ◽

Quantum Field ◽

Wave Fronts ◽

Sufficient And Necessary Condition

The Ryu–Takayanagi formula provides the entanglement entropy of quantum field theory as an area of the minimal surface (Ryu–Takayanagi surface) in a corresponding gravity theory. There are some attempts to understand the formula as a flow rather than as a surface. In this paper, we consider null rays emitted from the AdS boundary and construct a flow representing the causal holographic information. We present a sufficient and necessary condition that the causal information surface coincides with Ryu–Takayanagi surface. In particular, we show that, in spherical symmetric static spacetimes with a negative cosmological constant, wave fronts of null geodesics from a point on the AdS boundary become extremal surfaces and therefore they can be regarded as the Ryu–Takayanagi surfaces. In addition, from the viewpoint of flow, we propose a wave optical formula to calculate the causal holographic information.

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Advances in String Theory in Curved Backgrounds: A Synthesis Report

International Journal of Modern Physics A ◽

10.1142/s0217751x0301543x ◽

2003 ◽

Vol 18 (12) ◽

pp. 2011-2022 ◽

Cited By ~ 3

Author(s):

N. G. Sanchez

Keyword(s):

Field Theory ◽

Quantum Field Theory ◽

String Theory ◽

Quantum Field ◽

De Sitter ◽

Conformal Field ◽

Dual Relation ◽

New Feature ◽

Synthesis Report ◽

Gravitational Wave Background

A synthetic report of the advances in the study of classical and quantum string dynamics in curved backgrounds is provided, namely : the new feature of Multistring solutions; the mass spectrum of Strings in Curved backgrounds; The effect of a Cosmological Constant and of Spacial Curvature on Classical and Quantum Strings; Classical splitting of Fundamental Strings; The General String Evolution in constant Curvature Spacetimes; The Conformal Invariance Effects; Strings on plane fronted and gravitational shock waves, string falling on spacetime singularities and its spectrum. New Developments in String Gravity and String Cosmology are reported: String driven cosmology and its Predictions; The primordial gravitational wave background; Non-singular string cosmologies from Exact Conformal Field Theories; Quantum Field Theory, String Temperature and the String Phase of de Sitter space-time; Hawking Radiation in String Theory and the String Phase of Black Holes; New Dual Relation between Quantum Field Theory regime and String regime and the "QFT/String Tango"; New Coherent String States and Minimal Uncertainty Principle in string theory.

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