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In this paper we write down the equation for a scalar conformally coupled field simultaneously for de Sitter (dS), anti-de Sitter (AdS) and Minkowski spacetime in d-dimensions. The curvature dependence appears in a very simple way through a…

General Relativity and Quantum Cosmology · Physics 2009-11-11 E. Huguet , J. Queva , J. Renaud

We consider the evolution of massive scalar fields in (asymptotically) de Sitter spacetimes of arbitrary dimension. Through the proposed dS/CFT correspondence, our analysis points to the existence of new nonlocal dualities for the Euclidean…

High Energy Physics - Theory · Physics 2009-11-07 Frederic Leblond , Donald Marolf , Robert C. Myers

We explore aspects of the physics of de Sitter (dS) space that are relevant to holography with a positive cosmological constant. First we display a nonlocal map that commutes with the de Sitter isometries, transforms the bulk-boundary…

High Energy Physics - Theory · Physics 2009-03-16 Vijay Balasubramanian , Jan de Boer , Djordje Minic

This paper is the second part of a series that develops the mathematical framework necessary for studying field theories on ``T-Minkowski'' noncommutative spacetimes. These spacetimes constitute a class of noncommutative geometries,…

High Energy Physics - Theory · Physics 2025-04-18 Flavio Mercati

Discrete symmetries, parity, time reversal, antipodal, and charge conjugation transformations for spinor field in de Sitter space, are presented in the ambient space notation, i.e. in a coordinate independent way. The PT and PCT…

General Relativity and Quantum Cosmology · Physics 2008-11-26 S. Moradi , S. Rouhani , M. V. Takook

Non-Hermiticity gives rise to unique topological phases without Hermitian analogs. However, the effective field theory has yet to be established. Here, we develop a field-theoretical description of the intrinsic non-Hermitian topological…

Mesoscale and Nanoscale Physics · Physics 2021-06-01 Kohei Kawabata , Ken Shiozaki , Shinsei Ryu

We discuss non-Hermitian field theories where the spectrum of the Hamiltonian involves only real energies. We make three observations. (i) The theories obtained from supersymmetric theories by nonanticommutative deformations belong in many…

High Energy Physics - Theory · Physics 2008-11-26 A. V. Smilga

In this paper we study a new symmetry argument that results in a vacuum state with strictly vanishing vacuum energy. This argument exploits the well-known feature that de Sitter and Anti- de Sitter space are related by analytic…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Gerard 't Hooft , Stefan Nobbenhuis

The nonlocal theory of accelerated systems is extended to linear gravitational waves as measured by accelerated observers in Minkowski spacetime. The implications of this approach are discussed. In particular, the nonlocal modifications of…

High Energy Physics - Theory · Physics 2009-11-11 Bahram Mashhoon

In this paper we study one-dimensional conformal field theory at finite temperature dual to the two-dimensional anti-de Sitter spacetime in the Rindler coordinates. We show that conformal symmetry for thermal two-point functions manifests…

High Energy Physics - Theory · Physics 2016-11-04 Satoshi Ohya

Before we ask what the quantum gravity theory is, it is a legitimate quest to formulate a robust quantum field theory in curved spacetime (QFTCS). Several conceptual problems, especially unitarity loss (pure states evolving into mixed…

High Energy Physics - Theory · Physics 2024-12-31 K. Sravan Kumar , João Marto

Deformations of quantum field theories which preserve Poincar\'e covariance and localization in wedges are a novel tool in the analysis and construction of model theories. Here a general scenario for such deformations is discussed, and an…

Mathematical Physics · Physics 2015-05-27 Gandalf Lechner

In this article, we formulate the study of the unitary time evolution of systems consisting of an infinite number of uncoupled time-dependent harmonic oscillators in mathematically rigorous terms. We base this analysis on the theory of a…

Mathematical Physics · Physics 2009-10-06 Daniel Gómez Vergel , Eduardo J. S. Villaseñor

An analogue of the Newton-Wigner position operator is defined for a massive neutral scalar field in de Sitter space. The one-particle subspace of the theory, consisting of positive-energy solutions of the Klein-Gordon equation selected by…

High Energy Physics - Theory · Physics 2015-05-20 N. Yokomizo , J. C. A. Barata

We analyze, in the paradigm of open quantum systems, the reduced dynamics of a freely-falling two-level detector in de Sitter space-time in weak interaction with a reservoir of fluctuating quantized conformal scalar fields in the de Sitter…

General Relativity and Quantum Cosmology · Physics 2011-02-23 Hongwei Yu

Here, we study a quantum fermion field in rigid rotation at finite temperature on anti-de Sitter space. We assume that the rotation rate $\Omega$ is smaller than the inverse radius of curvature $\ell ^{-1}$, so that there is no speed of…

High Energy Physics - Theory · Physics 2022-02-16 Victor E. Ambrus , Elizabeth Winstanley

We investigate the moduli space of conformal field theories by setting up a canonical mathematical process for exponentiating perturbations corresponding to critical fields. We apply this process to the free field theory and the Gepner…

High Energy Physics - Theory · Physics 2010-04-07 Igor Kriz

We study two-point functions of symmetric traceless local operators in the bulk of de Sitter spacetime. We derive the K\"all\'en-Lehmann spectral decomposition for any spin and show that unitarity implies its spectral densities are…

High Energy Physics - Theory · Physics 2025-07-10 Manuel Loparco , Joao Penedones , Kamran Salehi Vaziri , Zimo Sun

We investigate the quantum-mechanical interpretation of models with non-Hermitian Hamiltonians and real spectra. After describing a general framework to reformulate such models in terms of Hermitian Hamiltonians defined on the Hilbert space…

Quantum Physics · Physics 2009-11-10 R. Kretschmer , L. Szymanowski

In order to resolve the measurement problem of Quantum Mechanics, non-unitary time evolution has been derived from the unitarity of standard quantum formalism. New wave functions of free and non-free quantum systems follow from Schroedinger…

Quantum Physics · Physics 2007-05-23 Pradip Kumar Chatterjee