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We study particles creation in arbitrary space-time dimensions by external electric fields, in particular, by fields, which are acting for a finite time. The time and dimensional analysis of the vacuum instability is presented. It is shown…

High Energy Physics - Theory · Physics 2014-11-18 S. P. Gavrilov , D. M. Gitman

We discuss particle production in spacetimes endowed with a universal horizon in Einstein--Aether and Horava gravity. We argue that continuity and differentiability of the lapse function require the orientation of the foliation in the…

General Relativity and Quantum Cosmology · Physics 2022-06-28 Francesco Del Porro , Mario Herrero-Valea , Stefano Liberati , Marc Schneider

We study production of light particles due to oscillation of the Hubble parameter or the scale factor. Any coherently oscillating scalar field, irrespective of its energy fraction in the universe, imprints such an oscillating feature on…

High Energy Physics - Phenomenology · Physics 2016-10-05 Yohei Ema , Ryusuke Jinno , Kyohei Mukaida , Kazunori Nakayama

In the present article we solve the Dirac equation in a de Sitter universe when a constant electric field is present. Using the Bogoliubov transformations, we compute the rate of spin 1/2 created particles by the electric field. We compare…

High Energy Physics - Theory · Physics 2016-08-15 Víctor M. Villalba

A characterization of the foliation by spacelike slices of an $(n+1)$-dimensional spatially closed Generalized Robertson-Walker spacetime is given by means of studying a natural mean curvature type equation on spacelike graphs. Under some…

Differential Geometry · Mathematics 2019-02-26 José A. S. Pelegrín , Alfonso Romero , Rafael M. Rubio

In this paper, we explore the particle creation scenario in the context of $f(\mathcal{G})$ gravity in flat-FLRW metric. For this purpose, from the perspective of thermodynamics and considering an adiabatic universe, we obtain the modified…

General Relativity and Quantum Cosmology · Physics 2025-05-30 S. Ganjizadeh , Alireza Amani , M. A. Ramzanpour

Our formalism described recently in (Dolby et al, hep-th/0103228) is applied to the study of particle creation in spatially uniform electric fields, concentrating on the cases of a time-invariant electric field and a so-called `adiabatic'…

High Energy Physics - Theory · Physics 2015-06-26 Carl E. Dolby , Stephen F. Gull

We study a stochastic version of the dynamical Casimir effect, computing the particle creation inside a cavity produced by a random motion of one of its walls. We first present a calculation perturbative in the amplitude of the motion. We…

Quantum Physics · Physics 2023-01-25 Matías Mantiñan , Francisco D. Mazzitelli , Leonardo G. Trombetta

This thesis investigates cosmological particle production within Quantum Field Theory in Curved Spacetimes, both as a dark matter mechanism and through analog simulations using Bose-Einstein condensates. While a full theory of Quantum…

General Relativity and Quantum Cosmology · Physics 2026-02-12 Álvaro Parra-López

An attempt is made to explain the spiral structure of spiral galaxies through a possible rotation of the Universe. To this end, we write down a possible form of the metric, and we calculate the necessary quantities (Rik, Tik, ...) in order…

Astrophysics · Physics 2009-04-27 Evangelos Chaliasos

We consider a global quantum system (the "Universe") satisfying a double constraint, both on total energy and total momentum. Generalizing the Page and Wootters quantum clock formalism, we provide a model of 3+1 dimensional,…

Quantum Physics · Physics 2022-11-10 Tommaso Favalli , Augusto Smerzi

We canonically quantize the dynamics of the brane universe embedded into the five-dimensional Schwarzschild-anti-deSitter bulk space-time. We show that in the brane-world settings the formulation of the quantum cosmology, including the…

General Relativity and Quantum Cosmology · Physics 2009-11-10 A. Boyarsky , A. Neronov , I. Tkachev

We investigate the fate of particle production in an expanding universe dominated by a perfect fluid with equation of state $p = \alpha\rho$. The rate of particle production, using the Bogolioubov coefficients, are determined exactly for…

General Relativity and Quantum Cosmology · Physics 2012-07-06 A. B. Batista , J. C. Fabris , M. J. S. Houndjo

The complex time WKB (CWKB) approximation has been an effective technique to understand particle production in curved as well as in flat spacetime. Earlier we obtained the standard results on particle production in time dependent gauge in…

Astrophysics · Physics 2015-06-24 S. Biswas , B. Modak , A. Shaw

We study the instantons describing the production of particles at the ends of codimension-one objects (strings and struts) in $(2+1)$-dimensional Minkowski and de Sitter spaces. A Minkowskian background allows only for systems with…

General Relativity and Quantum Cosmology · Physics 2019-11-18 Liam O'Brien , Lorenzo Sorbo

We analyse the smooth and sharp creation of a pointlike source for a quantised massless scalar field in $(3+1)$-dimensional Minkowski spacetime, as a model for the breakdown of correlations that has been proposed to occur at the horizon of…

High Energy Physics - Theory · Physics 2017-04-25 L. J. Zhou , Margaret E. Carrington , Gabor Kunstatter , Jorma Louko

For scalar and electromagnetic fields we evaluate the vacuum expectation value of the energy-momentum tensor induced by a curved boundary in the Robertson--Walker spacetime with negative spatial curvature. In order to generate the vacuum…

High Energy Physics - Theory · Physics 2010-04-30 A. A. Saharian , M. R. Setare

The problem of cosmological particle creation for a spatially flat, homogeneous and isotropic Universes is discussed in the context of f(R) theories of gravity. Different from cosmological models based on general relativity theory, it is…

Cosmology and Nongalactic Astrophysics · Physics 2011-07-01 S. H. Pereira , C. H. G. Bessa , J. A. S. Lima

In modeling relativistic thermodynamics, we frequently regard the particle number as a conserved quantity. The number conservation law, which comes from the requirement that the pull-back construction from fluid-matter 3-space has the same…

General Relativity and Quantum Cosmology · Physics 2022-09-26 Hyeong-Chan Kim

This study reconsiders the decay of an ordinary particle in bradyons, tachyons and luxons in the field of the relativistic quantum mechanics. Lemke already investigated this from the perspective of covariant kinematics. Since the decay…

General Physics · Physics 2018-06-04 Luca Nanni