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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

In this work, we investigate Big Bang Nucleosynthesis (BBN) within the framework of $f(T,{L}_m)$ gravity, where the gravitational Lagrangian is generalized as a function of the torsion scalar $T$ and the matter Lagrangian ${L}_m$. We…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-25 Daniel F. P. Cruz , David S. Pereira , Francisco S. N. Lobo , José P. Mimoso

The Gauss-Bonnet invariant connects foundational aspects of geometry with physical phenomena in a variety of ways. Teleparallel gravity offers a novel direction in which to use the Gauss-Bonnet invariant to go beyond standard cosmology. In…

General Relativity and Quantum Cosmology · Physics 2026-04-21 Shivam Kumar Mishra , Jackson Levi Said , B. Mishra

We study the spontaneous baryogenesis scenario in the early universe for three different frameworks of varying constants theories. We replace the constants by dynamical scalar fields playing the role of thermions. We first obtain the…

High Energy Physics - Theory · Physics 2019-03-27 Katarzyna Leszczynska , Mariusz P. Dabrowski , Tomasz Denkiewicz

Recently, the scalar-tensor representation of $f (R,T)$ gravity was used to explore gravitationally induced particle production/annihilation. Using the framework of irreversible thermodynamics of open systems in the presence of matter…

General Relativity and Quantum Cosmology · Physics 2023-10-20 Amine Bouali , Himanshu Chaudhary , Tiberiu Harko , Francisco S. N. Lobo , Taoufik Ouali , Miguel A. S. Pinto

In recent years, modifications to General Relativity (GR) have been explored to address cosmological observations, particularly in the context of late-time cosmic acceleration. Among these, modifications based on the Teleparallel Equivalent…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-29 Saurabh Verma , Archana Dixit , Anirudh Pradhan , M. S. Barak

Big Bang Nucleosynthesis provides us with an observational insight into the very early Universe. Since this mechanism of light element synthesis comes out of the standard model of particle cosmology which follows directly from General…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-14 Sai Swagat Mishra , Ameya Kolhatkar , P. K. Sahoo

During inflation primordial quantum fluctuations of the spacetime metric become classical and there is a spontaneous CPT violation by the spin connection coupling terms of the metric with fermions. The energy levels of the left and the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Subhendra Mohanty , B. Mukhopadhyay , A. R. Prasanna

This study proposes a unified framework comprising two complementary approaches to constrain three functional forms of $f(T,B)$ gravity, namely the linear, quadratic, and general power law models, by jointly utilizing early and late…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-07 Yahia Al-Omar , Majida Nahili , Nidal Chamoun , Marwan Al-Raeei

We present a multi-epoch test of f(T) gravity with nonminimal torsion-matter coupling, combining early- and late-Universe observations. At the MeV scale, Big-Bang Nucleosynthesis constrains the fractional variation of the weak freeze-out…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-27 Yahia Al-Omar , Majida Nahili , Nidal Chamoun

In this paper, we have presented an accelerating cosmological model of the Universe in an extended symmetric teleparallel gravity or $f(Q,T)$ gravity. The parametric form of the Hubble parameter is, $H\left(z\right) =H_{0}\left[ \alpha…

General Relativity and Quantum Cosmology · Physics 2023-05-16 S. A. Narawade , M. Koussour , B. Mishra

Lorentz-violating theories of gravity typically contain constrained vector fields. We show that the lowest-order coupling of such vectors to $\mathrm{U}(1)$-symmetric scalars can naturally give rise to baryogenesis in a manner akin to the…

High Energy Physics - Phenomenology · Physics 2017-09-14 Jeremy Sakstein , Adam R. Solomon

We consider the cosmological implications of a four-dimensional extension of the Gauss-Bonnet $f(G)$ gravity, where $G$ is the Gauss-Bonnet topological invariant, in which the Einstein-Hilbert action is replaced by an arbitrary function…

General Relativity and Quantum Cosmology · Physics 2025-06-23 Ratul Mandal , Himanshu Chaudhary , Tiberiu Harko , Ujjal Debnath , G. Mustafa

Generalised Teleparallel gravity, also referred to as f(T) gravity, has been recently proposed as an extended theory of gravitation able to give rise to an accelerated expansion in a matter only universe. The cosmic speed up is driven by an…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Vincenzo F. Cardone , Ninfa Radicella , Stefano Camera

This thesis investigates modified teleparallel gravity models with a scalar field and teleparallel boundary terms, focusing on their cosmological implications for late-time cosmic acceleration. Teleparallel gravity, is an alternative to…

General Relativity and Quantum Cosmology · Physics 2025-01-22 S. A. Kadam

We investigate two new observational perspectives in the context of torsional gravitational modification of general relativity, i.e., the $f(T)$ gravity: i) We use Pantheon data of type Ia supernovae motivated by a time variation of the…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-21 Suresh Kumar , Rafael C. Nunes , Priya Yadav

The expansion of the Universe in $f(R,T)$ gravity is studied. We consider functions of the form $f(R,T)=R+\lambda T^\epsilon$ where $\epsilon<1$. We find that for all models with $\epsilon<0$, the Universe transitions to exponential growth…

General Relativity and Quantum Cosmology · Physics 2026-03-26 Vincent R. Siggia , Eric D. Carlson , P. Lee Pryor

All degrees of freedom related to the torsion scalar can be explored by analysing, the $f(T,T_G)$ gravity formalism where, $T$ is a torsion scalar and $T_G$ is the teleparallel counterpart of the Gauss-Bonnet topological invariant term. The…

General Relativity and Quantum Cosmology · Physics 2023-03-27 S. A. Kadam , B. Mishra , Jackson Levi Said

We generalize the mechanism for gravitational baryogensis in the context of $f(R)$ theories of gravity, including a nonminimal coupling between curvature and matter. In these models, the baryon asymmetry is generated through an effective…

General Relativity and Quantum Cosmology · Physics 2017-11-22 M. P. L. P. Ramos , J. Páramos

The study conducted in this research paper utilizes the $f(Q,T)$ gravity, where $Q$ represents non-metricity and $T$ represents the trace of the energy-momentum tensor, to investigate the accelerated expansion of the universe. To complete…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-17 M. Koussour , N. Myrzakulov , J. Rayimbaev , A. Errehymy , Orhan Donmez