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Related papers: Dynamical Evolution of Gravitational Leptogenesis

200 papers

We examine recent claims for a considerable amount of leptogenesis, in some inflationary scenarios, through the gravitational anomaly in the lepton number current. We find that when the short distances contributions are properly included…

High Energy Physics - Theory · Physics 2008-11-26 W. Fischler , S. Paban

An analytical solution for time evolution of the gravitational wave damping in the early Universe due to freely streaming neutrinos is found in the late time regime. The solution is represented by a convergent series of spherical Bessel…

General Relativity and Quantum Cosmology · Physics 2012-08-01 Gavriil Shchedrin

We present an intrinsic leptogenesis mechanism in models of axion inflation with a classical SU(2) gauge field. The gauge field is coupled to the axion with a Chern-Simons interaction and comprises a tiny fraction of the total energy,…

High Energy Physics - Phenomenology · Physics 2016-12-21 Azadeh Maleknejad

In seesaw mechanism, if right handed (RH) neutrino masses are generated dynamically by a gauged $U(1)$ symmetry breaking, a stochastic gravitational wave background (SGWB) sourced by a cosmic string network could be a potential probe of…

High Energy Physics - Phenomenology · Physics 2023-01-11 Rome Samanta , Satyabrata Datta

We revisit the gravitational leptogenesis scenario in which the inflaton is coupled to gravity by the Chern-Simons term and the lepton asymmetry is generated through the gravitational anomaly in the lepton number current during inflation.…

High Energy Physics - Phenomenology · Physics 2020-02-05 Kohei Kamada , Jun'ya Kume , Yusuke Yamada , Jun'ichi Yokoyama

The mechanism of gravitational baryogenesis, based on the CPT-violating gravitational interaction between the derivative of the Ricci scalar curvature and the baryon-number current, is investigated in the context of the Gauss-Bonnet…

High Energy Physics - Phenomenology · Physics 2009-11-11 M. C. Bento , R. Gonzalez Felipe , N. M. C. Santos

There is an effect in the modified dynamics (MOND) that is conducive to formation of warps. Because of the nonlinearity of the theory the internal dynamics of a galaxy is affected by a perturber over and above possible tidal effects. For…

Astrophysics · Physics 2009-10-31 Rafael Brada , Mordehai Milgrom

We demonstrate that induced gravitational waves (IGWs) can naturally emerge within the framework of thermal leptogenesis models, thereby providing a robust probe for exploring this theory at remarkably high energy scales. To illustrate this…

High Energy Physics - Phenomenology · Physics 2025-09-29 Marco Chianese , Guillem Domènech , Theodoros Papanikolaou , Rome Samanta , Ninetta Saviano

We present a new approach to gauge-invariant cosmological perturbations at second order, which is also covariant. We examine two cases in particular for a dust Friedman-Lemaitre-Robertson-Walker model of any curvature: we investigate…

Astrophysics · Physics 2014-10-13 Chris Clarkson

We consider the possibility of a gravitationally induced particle production through the mechanism of a nonminimal curvature-matter coupling. An interesting feature of this gravitational theory is that the divergence of the energy-momentum…

General Relativity and Quantum Cosmology · Physics 2015-08-31 Tiberiu Harko , Francisco S. N. Lobo , José P. Mimoso , Diego Pavón

Structure formation heralds the era of deviation of the matter content of the Universe away from thermal equilibrium, so the gravitational contribution to entropy, in the form of Weyl curvature, must become active in order for the overall…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-03 Fan Zhang

We relate leptogenesis in a class of theories to low-energy experimental observables: quark and lepton masses and mixings. With reasonable assumptions motivated by grand unification, one can show that the CP-asymmetry parameter takes a…

High Energy Physics - Phenomenology · Physics 2009-11-07 M. S. Berger , Kim Siyeon

The Kepler problem is considered in a space with the Friedmann--Lemaitre--Robertson--Walker metrics of the expanding universe. The covariant differential of the Friedmann coordinates (X=a(t)x) is considered as a possible mechanism of the…

Astrophysics · Physics 2009-11-07 A. Gusev , P. Flin , V. Pervushin , S. Vinitsky , A. Zorin

We propose the gravitational analog of the chiroptical effect for the first time, demonstrating that gravitational waves (GWs) can induce a reversal of photon chirality through the exchange of angular momentum, namely the spin-2-gravitation…

General Relativity and Quantum Cosmology · Physics 2026-01-13 Haorong Wu , Xilong Fan

The recent observation of $^4$He favors a large lepton asymmetry at the big bang nucleosynthesis. If Q-balls with a lepton charge decay after the electroweak phase transition, such a large lepton asymmetry can be generated without producing…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-07 Shinta Kasuya , Masahiro Kawasaki , Kai Murai

Baryogenesis driven by curvature effects is investigated by taking into account gravitationally induced particle production in the very early Universe. In our scenario, the baryon asymmetry is generated dynamically during an inflationary…

General Relativity and Quantum Cosmology · Physics 2016-11-23 J. A. S. Lima , Douglas Singleton

The generation of a matter-antimatter asymmetry in the Universe may be induced by the propagation of fermions in non-trivial, spherically asymmetric (and hence Lorentz violating) gravitational backgrounds. Such backgrounds may characterise…

High Energy Physics - Phenomenology · Physics 2015-06-18 Nick E. Mavromatos , Sarben Sarkar

Using the quantum chromodynamics (QCD) equation of state (EoS) from lattice calculations we investigate effects from QCD on primordial gravitational waves (PGWs) produced during the inflationary era. We also consider different cases for…

High Energy Physics - Phenomenology · Physics 2019-05-23 Fazlollah Hajkarim , Jürgen Schaffner-Bielich , Stephan Wystub , Mandy M. Wygas

We show that Loop Quantum Gravity provides new mechanisms through which observed matter-antimatter asymmetry in the Universe can naturally arise at temperatures less than GUT scale. This is enabled through the introduction of a new length…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Gaetano Lambiase , Parampreet Singh

It is shown that a first-order relativistic perturbation theory for the open, flat or closed Friedmann-Lemaitre-Robertson-Walker universe admits one, and only one, gauge-invariant quantity which describes the perturbation to the energy…

General Relativity and Quantum Cosmology · Physics 2014-03-25 P. G. Miedema