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We study the particle creation process in the Schwinger model coupled with an external classical source. One can approach the problem by taking advantage that the full quantized model is solvable and equivalent to a (massive) gauge field…

High Energy Physics - Theory · Physics 2022-11-29 José Navarro-Salas , Silvia Pla

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

In this work we consider particle creation by the expansion of the universe, using two Bianchi type I anisotropic models. The particles studied are of spin 0 and 1/2. The cosmological models have rotational symmetry, which allows us to…

General Relativity and Quantum Cosmology · Physics 2021-07-07 Luis O. Pimentel , Flavio Pineda

In the present article we analyze the phenomenon of particle creation in a cosmological anisotropic universe when a constant electric field is present. We compute, via the Bogoliubov transformations, the density number of particles created.

High Energy Physics - Theory · Physics 2009-10-31 Victor M. Villalba

We exactly calculate the particle number $N$ of scalar fields which are created from an initial vacuum in certain higher-dimensional cosmological models. The spacetimes in these models are the four-dimensional Chitre-Hartle or…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Wung-Hong Huang

Recently, the phenomenological description of cosmological particle production processes in terms of effective viscous pressures has attracted some attention. Using a simple creation rate model we discuss the question to what extent this…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Josep Triginer , Winfried Zimdahl , Diego Pavon

Gravitational particle production is a minimal contribution to reheating the Universe after the end of inflation. To study this production channel, two different approaches have commonly been considered, one of which is based on the…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-08 Kunio Kaneta , Sung Mook Lee , Kin-ya Oda

This paper discusses particle production in Schwarzchild-like spacetimes and in an uniform electric field. Both problems are approached using the method of complex path analysis. Particle production in Schwarzchild-like spacetimes with a…

General Relativity and Quantum Cosmology · Physics 2008-11-26 K. Srinivasan , T. Padmanabhan

The method is proposed for the phenomenological description of particle creation by external fields (in the presence of gravitational field or without it). It is shown that, despite the appearance of the non-dynamical degrees of freedom,…

General Relativity and Quantum Cosmology · Physics 2014-04-15 Victor Berezin

Cosmological gravitational particle production (GPP) is a generic mechanism by which particles are produced during the inflationary epoch. In this work we consider the GPP of massive scalars in an effort to fully understand the spectrum of…

High Energy Physics - Phenomenology · Physics 2025-01-13 Leah Jenks , Edward W. Kolb , Keyer Thyme

It is well known that the expansion of the universe can create particles. However, due to ambiguities when defining particles during the expansion, there are still debates about how to choose vacuum and particle states. To clarify how…

General Relativity and Quantum Cosmology · Physics 2025-06-23 Philip Semrén

In this work we study the particle production in time dependent periodic potential using the method of complex time WKB (CWKB) approximation. In the inflationary cosmology at the end of inflationary stage, the potential becomes time…

General Relativity and Quantum Cosmology · Physics 2015-06-25 S. Biswas , P. Misra , I. Chowdhury

In this paper we have studied the problem of scalar particles pair creation by an electric field in the presence of a minimal length. Two sets of exact solutions for the Klein Gordon equation are given in momentum space. Then the canonical…

High Energy Physics - Theory · Physics 2014-06-11 S. Haouat , K. Nouicer

We study particle production in infrared-modified gravitational theories in the contemporary universe. It is shown that in astronomical systems with rising mass density, the curvature scalar may oscillate with very high frequency. These…

General Relativity and Quantum Cosmology · Physics 2015-06-16 E. V. Arbuzova , A. D. Dolgov , L. Reverberi

The spontaneous loss of angular momentum of a spinning cosmic string due to particle emission is discussed. The rate of particle production between two assymptotic spacetimes: the spinning cosmic string spacetime in the infinite past and a…

General Relativity and Quantum Cosmology · Physics 2014-11-17 V. A. De Lorenci , R. De Paola , N. F. Svaiter

Particle production in cosmology is often efficiently computed in terms of Bogoliubov transforms. Restricting to a particular class of dispersion relationships, we identify a map between the number of particles produced in a special…

High Energy Physics - Theory · Physics 2025-06-18 Daniel J. H. Chung , Nidhi Sudhir

The theory of quantum fields in classical backgrounds is re-examined for the cases in which the Lagrangian is quadratic in quantum fields. Various methods that describe particle production are discussed. It is found that all methods suffer…

High Energy Physics - Theory · Physics 2016-09-06 H. Nikolic

We show that the amount of particle production in an arbitrary cosmological background can be determined using only the late-time positive-frequency modes. We don't refer to modes at early times, so there is no need for a Bogolubov…

High Energy Physics - Theory · Physics 2009-11-10 Alex J. Hamilton , Daniel Kabat , Maulik K. Parikh

We present universal formulas for particle production from gravitational inhomogeneities. In the massless limit the result is strikingly simple and completely determined by the two-point function of the energy-momentum tensor that is fixed…

High Energy Physics - Theory · Physics 2025-03-03 Raghuveer Garani , Michele Redi , Andrea Tesi

We perform a qualitative and thermodynamic study of two models when one takes into account adiabatic particle production. In the first one, there is a constant particle production rate, which leads to solutions depicting the current cosmic…

General Relativity and Quantum Cosmology · Physics 2017-03-13 Llibert Aresté Saló , Jaume de Haro