English
Related papers

Related papers: Can particle creation phenomena replace dark energ…

200 papers

To explain the acceleration of the cosmological expansion researchers have considered an unusual form of mass-energy generically called dark energy. Dark energy has a ratio of pressure over mass density which obeys $w=p/\rho <-1/3$. This…

High Energy Physics - Theory · Physics 2008-12-19 Max Chaves , Douglas Singleton

This lecture course covers cosmology from the particle physicist perspective. Therefore, the emphasis will be on the evidence for the new physics in cosmological and astrophysical data together with minimal theoretical frameworks needed to…

General Relativity and Quantum Cosmology · Physics 2018-02-09 Igor Tkachev

A continuous process of creation of particles is investigated as a possible connection between the inflationary stage with late cosmic acceleration. In this model, the inflationary era occurs due to a continuous and fast process of creation…

General Relativity and Quantum Cosmology · Physics 2016-04-27 Rafael C. Nunes

The existence of dark matter and dark energy in cosmology is implied by various observations, however, they are still unclear because they have not been directly detected. In this Letter, an unified model of dark energy and dark matter that…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-27 Jiro Matsumoto

The physical basis of the modern cosmological inflationary models with baryosynthesis and nonbaryonic dark matter and energy implies such predictions of particle theory, that, in turn, apply to cosmology for their test. It makes physics of…

Astrophysics · Physics 2007-05-23 Maxim Yu. Khlopov

Observations show that the expansion of the Universe is accelerating. This requires that the dominant constituent of matter in the Universe has some unusual properties like negative pressure. This exotic component has been given the name…

Popular Physics · Physics 2019-01-17 Manvendra Pratap Rajvanshi , Tuneer Chakraborty , J. S. Bagla

It is shown that a first-order cosmological perturbation theory for Friedmann-Lemaitre-Robertson-Walker universes admits one and only one gauge-invariant variable which describes the perturbation to the energy density and which becomes…

General Relativity and Quantum Cosmology · Physics 2015-03-13 P. G. Miedema

The recent observational evidence for the current cosmic acceleration have stimulated renewed interest in alternative cosmologies, such as scenarios with interaction in the dark sector (dark matter and dark energy). In general, such models…

Cosmology and Nongalactic Astrophysics · Physics 2009-10-22 R. S. Goncalves , J. S. Alcaniz , A. Dev , D. Jain

A dark-energy-free cosmological model ($\Omega_{DE} \equiv 0$) based on gravitationally induced adiabatic particle creation is proposed. The thermodynamics of particle production yields an effective negative pressure that drives both…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-18 P. W. R. Lima , J. A. S. Lima

Using a model for an ideal fluid with a variable number of particles, a phenomenological description of the processes of particle production in strong external fields is investigated. The conformal invariance of the creation law is shown,…

General Relativity and Quantum Cosmology · Physics 2023-12-13 Victor Berezin , Inna Ivanova

We examine how the existence of a population of primordial black holes (PBHs) influences cosmological gravitational particle production (CGPP) for spin-0 and spin-1 particles. In addition to the known effects of particle production and…

High Energy Physics - Phenomenology · Physics 2025-06-03 Enrico Bertuzzo , Yuber F. Perez-Gonzalez , Gabriel M. Salla , Renata Zukanovich Funchal

Cosmological production of scalar, non-minimally coupled dark matter depends on the specifics of the inflationary model under consideration. We analyze both Starobinsky inflation and a quadratic potential, solve the full background…

General Relativity and Quantum Cosmology · Physics 2026-02-24 Jose A. R. Cembranos , Luis J. Garay , Álvaro Parra-López , Javier Ortega del Río

We explore the possibility of gravitationally generated particle production in the scalar-tensor representation of $f(R,T)$ gravity. Due to the explicit nonminimal curvature-matter coupling in the theory, the divergence of the matter…

General Relativity and Quantum Cosmology · Physics 2022-09-02 Miguel A. S. Pinto , Tiberiu Harko , Francisco S. N. Lobo

We investigate the production of dark matter from curvature perturbations produced during inflation or in standard cosmology, for example during first order phase transitions. Perturbations break Weyl flatness of the…

High Energy Physics - Phenomenology · Physics 2024-09-06 Raghuveer Garani , Michele Redi , Andrea Tesi

The inadequacy of the present cosmological picture is underlined. The central issue of energy and particles-photons number conservation is addressed. It is shown that consideration of gravitational self energy is paramount both for matter…

General Physics · Physics 2011-12-09 Paolo Christillin

The formation of structure in the Universe offers some of the most powerful evidence in favour of the existence of dark matter in the Universe. We summarize recent work by ourselves and our collaborators, using linear and quasi-linear…

Astrophysics · Physics 2007-05-23 Andrew R Liddle , Pedro T P Viana

We propose a simple model in which the cosmological dark matter consists of particles whose mass increases with the scale factor of the universe. The particle mass is generated by the expectation value of a scalar field which does not have…

Astrophysics · Physics 2016-10-26 Greg W. Anderson , Sean M. Carroll

We present a simple and thermodynamically consistent cosmology with a phenomenological model of quantum creation of radiation due to vacuum decay. Thermodynamics and Einstein's equations lead to an equation in which $H$ is determined by the…

Astrophysics · Physics 2008-11-26 E Gunzig , R Maartens , A Nesteruk

Recent cosmological observations indicate the existence of extra light species, i.e., dark radiation. In this paper we show that signatures of the dark radiation are imprinted in the spectrum of inflationary gravitational waves. If the dark…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Ryusuke Jinno , Takeo Moroi , Kazunori Nakayama

The present work deals with a cosmological model having particle creation mechanism in the framework of irreversible thermodynamics. In the second order non-equilibrium thermodynamical prescription, the particle creation rate is treated as…

General Relativity and Quantum Cosmology · Physics 2015-05-01 Subenoy Chakraborty , Supriya Pan , Subhajit Saha
‹ Prev 1 3 4 5 6 7 10 Next ›