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This paper deals with the cancellation mechanism, which identifies the energy density of space-time expansion in an empty universe with the zero-point energy density and avoids the scale discrepancy with the observed energy density…

综合物理 · 物理学 2018-06-12 Christian Henke

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…

广义相对论与量子宇宙学 · 物理学 2022-09-02 Miguel A. S. Pinto , Tiberiu Harko , Francisco S. N. Lobo

The matter creation cosmology is revisited, including the evolution of baryons and dark matter particles. The creation process affects only dark matter and not baryons. The dynamics of the $\Lambda$CDM model can be reproduced only if two…

宇宙学与河外天体物理 · 物理学 2014-07-08 J. C. Fabris , J. A. de Freitas Pacheco , O. F. Piattella

The study of particle creation phenomena at the expense of the gravitational field is of great research interest. It might solve the cosmological puzzle single-handedly, without the need for either dark energy or the modified theory of…

广义相对论与量子宇宙学 · 物理学 2018-06-26 Abhik Kumar Sanyal , Subhra Debnath

A constant-rate creation of dark particles in the late-time FLRW spacetime provides a cosmological model in accordance with precise observational tests. The matter creation backreaction implies in this context a vacuum energy density…

宇宙学与河外天体物理 · 物理学 2014-05-27 Saulo Carneiro

We investigate a spatially flat Friedmann-Lema\^itre-Robertson-Walker cosmology in which a decaying vacuum term causes matter production at late times. Assuming a decay proportional to the Hubble rate, the ratio of the background energy…

宇宙学与河外天体物理 · 物理学 2011-08-26 W. Zimdahl , H. A. Borges , S. Carneiro , J. C. Fabris , W. S. Hipólito-Ricaldi

We show that a cosmology driven by gravitationally induced particle production of all non-relativistic species existing in the present Universe mimics exactly the observed flat accelerating $\Lambda$CDM cosmology with just one dynamical…

广义相对论与量子宇宙学 · 物理学 2016-03-23 J. A. S. Lima , R. C. Santos , J. V. Cunha

The evolution of the wave function in quantum mechanics is deterministic like that of classical waves. Only when we bring in observers the fundamentally different quantum reality emerges. Similarly the introduction of observers changes the…

综合物理 · 物理学 2020-10-16 Jan O. Stenflo

We propose an alternative scenario for the dark matter generation from an evolving cosmological constant which interacts with the dominant background in certain intermediate phase of the universe, and relaxes to the observed small value at…

宇宙学与河外天体物理 · 物理学 2013-01-01 Murli Manohar Verma

We investigate the possibility of gravitationally generated particle production via the mechanism of nonminimal torsion--matter coupling. An intriguing feature of this theory is that the divergence of the matter energy--momentum tensor does…

广义相对论与量子宇宙学 · 物理学 2021-07-06 Tiberiu Harko , Francisco S. N. Lobo , Emmanuel N. Saridakis

We investigate the creation of cold dark matter (CCDM) cosmology as an alternative to explain the cosmic acceleration. Particular attention is given to the evolution of density perturbations and constraints coming from recent observations.…

宇宙学与河外天体物理 · 物理学 2014-04-11 Rudnei O. Ramos , Marcelo Vargas dos Santos , Ioav Waga

The matter creation model of Prigogine--G\'eh\'eniau--Gunzig--Nardone is revisited in terms of a redefined creation pressure which does not lead to irreversible adiabatic evolution at constant specific entropy. With the resulting freedom to…

广义相对论与量子宇宙学 · 物理学 2022-09-15 Rossen I. Ivanov , Emil M. Prodanov

The Hubble tension and the unknown origin of dark energy motivate the exploration of alternative mechanisms for late-time cosmic acceleration. We investigate gravitationally induced particle creation (PC) as a non-equilibrium process that…

宇宙学与河外天体物理 · 物理学 2026-04-28 Tiziano Schiavone , Mariaveronica De Angelis , Luis A. Escamilla , Giovanni Montani , Eleonora Di Valentino

In this Letter we discuss the issues of the graceful exit from inflation and of matter creation in the context of a recent scenario \cite{RHBrev} in which the back-reaction of long wavelength cosmological perturbations induces a negative…

高能物理 - 理论 · 物理学 2009-11-10 Robert Brandenberger , Anupam Mazumdar

Quantum theory of a test field on a quantum cosmological spacetime may be viewed as a theory of the test field on an emergent classical background. In such a case, the resulting dressed metric for the field propagation is a function of the…

广义相对论与量子宇宙学 · 物理学 2021-07-23 Yaser Tavakoli

In this paper we have given a generalisation of the earlier work by Prigogine et al. who have constructed a phenomenological model of entropy production via particle creation in the very early universe generated out of the vacuum rather…

广义相对论与量子宇宙学 · 物理学 2015-06-05 G. K. Goswami , Mandwi Trivedi

We introduce the hypothesis that the matter content of the universe can be a product of the decay of primordial vector bosons. The effect of the intensive cosmological creation of these primordial vector $W, ~Z $ bosons from the vacuum is…

高能物理 - 理论 · 物理学 2016-09-06 D. Blaschke , V. Pervushin , D. Proskurin , S. Vinitsky , A. Gusev

In massless scalar field cosmology, imposing the universe's physical volume as fundamentally discrete resolves the big bang singularity via a big bounce. We use quantum field theory on curved background to numerically track the number of…

广义相对论与量子宇宙学 · 物理学 2025-10-16 Mustafa Saeed , Irfan Javed , Aiman Nauman

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…

广义相对论与量子宇宙学 · 物理学 2017-03-13 Llibert Aresté Saló , Jaume de Haro

On the basis of a previously established scalar-tensor extension of the $\Lambda$CDM model we develop an effective fluid approach for the matter growth function. This extended $\Lambda$CDM (henceforth $e_{\Phi}\Lambda$CDM) cosmology takes…

宇宙学与河外天体物理 · 物理学 2019-05-01 W. Zimdahl , H. E. S. Velten , W. C. Algoner