English
Related papers

Related papers: Standard Model Extension with Gravity and Gravitat…

200 papers

We discuss two cosmological issues in a generic gauge-mediated supersymmetry (SUSY)-breaking model, namely the Universe's baryon asymmetry and the gravitino dark-matter density. We show that both problems can be simultaneously solved if…

High Energy Physics - Phenomenology · Physics 2009-11-07 Masaaki Fujii , T. Yanagida

Baryogenesis refers to the theoretical process that occurred in the early history of the universe producing excess of matter over antimatter. Hitherto, fundamental physics which can give rise to such events is unknown. Many theories have…

General Physics · Physics 2020-05-13 P. K. Sahoo , Snehasish Bhattacharjee

We propose a new model of gravity where the Ricci scalar (R) in Einstein-Hilbert action is replaced by an arbitrary function of R and of the norm of energy-momentum tensor i.e., $f(R,T_{\mu\nu}T^{\mu\nu})$. Field equations are derived in…

General Relativity and Quantum Cosmology · Physics 2014-08-04 N. Katirci , Mehmet Kavuk

We review and extend the recently proposed model of combinatorial quantum gravity. Contrary to previous discrete approaches, this model is defined on (regular) random graphs and is driven by a purely combinatorial version of Ricci…

High Energy Physics - Theory · Physics 2020-01-08 C. Kelly , C. A. Trugenberger

Some bouncing models are investigated in the framework of an extended theory of gravity. The extended gravity model is a simple extension of the General Relativity where an additional matter geometry coupling is introduced to account for…

General Relativity and Quantum Cosmology · Physics 2021-06-10 S K Tripathy , B Mishra , Saibal Ray , Rikpratik Sengupta

We present cosmological perturbation theory based on generalized gravity theories including string theory correction terms and a tachyonic complication. The classical evolution as well as the quantum generation processes in these variety of…

General Relativity and Quantum Cosmology · Physics 2009-11-10 J. Hwang , H. Noh

We consider a model of noncommutative gravity that is based on a spacetime with broken local SO(2,3) symmetry. We show that the torsion-free version of this model is contained within the framework of the Lorentz-violating Standard-Model…

High Energy Physics - Theory · Physics 2018-10-12 Quentin G. Bailey , Charles D. Lane

Modification of gravity due to the curvature dependent term in the gravitational baryogenesis scenario is considered. It is shown that this term leads to the fourth order differential equation of motion for the curvature scalar instead of…

General Relativity and Quantum Cosmology · Physics 2017-04-05 E. V. Arbuzova , A. D. Dolgov

A popular class of theories attributes the matter-antimatter asymmetry of the Universe to CP-violating decays of super-heavy BSM particles in the Early Universe. Recently, we discovered a new source of leptogenesis in these models, namely…

High Energy Physics - Phenomenology · Physics 2017-04-12 J. I. McDonald , G. M. Shore

We propose that the baryon asymmetry of the Universe may originate from the amplification of quantum fluctuations of a light complex scalar field during inflation. CP-violation is sourced by complex mass terms, which are smaller than the…

Astrophysics · Physics 2008-12-18 Bjorn Garbrecht , Tomislav Prokopec

The origin of matter domination in the Universe is one of the most exciting open puzzles in particle physics and cosmology. Despite many theoretical developments, the actual reason behind baryon-antibaryon asymmetry is still unknown. Our…

General Relativity and Quantum Cosmology · Physics 2024-04-15 Sai Swagat Mishra , Aaqid Bhat , P. K. Sahoo

A novel mechanism of baryogenesis is proposed on the basis of the phase transition from the conformal invariant space-time to the Einstein space-time in quantum gravity. Strong-coupling gravitational excitations with dynamical mass about…

High Energy Physics - Phenomenology · Physics 2008-11-26 Ken-ji Hamada , Azusa Minamizaki , Akio Sugamoto

We investigate the observed asymmetry between matter and antimatter by incorporating higher-order matter contributions in gravity, specifically analyzing gravitational baryogenesis within the framework of $ f(R,\mathcal{T}^2) $ gravity,…

General Relativity and Quantum Cosmology · Physics 2025-05-09 David S. Pereira , Francisco S. N. Lobo , José Mimoso

The inability of primordial baryonic density fluctuations, as observed in the cosmic microwave background (CMB), to grow into the present day astronomical structures is well established, under Newtonian and Einsteinian gravity. It is hence…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-03 X. Hernandez , M. A. Jimenez

We argue that inflationary dynamics may support a scenario where significant matter-antimatter asymmetry is generated from initially small-scale quantum fluctuations that are subsequently stretched out over large scales. This scenario can…

High Energy Physics - Phenomenology · Physics 2015-06-18 Neil D. Barrie , Archil Kobakhidze

Wash-in leptogenesis is an attractive mechanism to produce the baryon asymmetry of the Universe. It treats right-handed-neutrino interactions as spectator processes, on the same footing as electroweak sphalerons, that reprocess primordial…

High Energy Physics - Phenomenology · Physics 2025-03-10 Martin A. Mojahed , Kai Schmitz , Xun-Jie Xu

We compute the gravitational leptogenesis generated from the parity-violating gravitational waves sourced by an abelian gauge field coupled to a pseudo-scalar inflation. We show that, once the CMB bound on the tensor-to-scalar ratio is…

Cosmology and Nongalactic Astrophysics · Physics 2017-12-20 Alexandros Papageorgiou , Marco Peloso

In this work, first we examine the energy conditions in the context of the generalized metric-Palatini hybrid gravity, known as $f(R, {\cal R})$ gravity. We show that for the proposed model in this study, {\it i.e.} $ f(R, {\cal R})= R…

General Relativity and Quantum Cosmology · Physics 2025-10-02 K. Atazadeh , S. Golsanamlou

Gravitational baryogenesis is one of the mechanisms which help us to explore more about our early universe, especially baryon-anti-baryon asymmetry. As we know, modified theories of gravity are very successful in describing the present…

General Relativity and Quantum Cosmology · Physics 2023-05-23 Sai Swagat Mishra , Sanjay Mandal , P. K. Sahoo

In this manuscript, we explore the baryon asymmetry of the universe by employing a novel higher-order extended uncertainty principle (EUP) that maintains a minimum length ${\rm{\Delta }}{x_{\rm min}} =4\sqrt {\left| {\rm{\beta_0 }}…

General Relativity and Quantum Cosmology · Physics 2023-08-29 Song-Shan Luo , Zhong-Wen Feng