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Related papers: Gravitational Leptogenesis in Bounce Cosmology

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Instead of creating the observed baryon asymmetry of the universe by the decay of right-handed (RH) neutrinos to left-handed leptons, we propose to generate it dominantly by the decay of the RH neutrinos to RH leptons. This mechanism turns…

High Energy Physics - Phenomenology · Physics 2009-11-11 Michele Frigerio , Thomas Hambye , Ernest Ma

We study the reheating and non-thermal leptogenesis in the case of a vector inflaton. We concentrate on particle production during the phase of oscillating background, especially gravitational production induced by the presence of…

High Energy Physics - Phenomenology · Physics 2024-12-17 Simon Cléry , Pascal Anastasopoulos , Yann Mambrini

An analysis of baryogenesis and stochastic gravitational wave production is presented for an extension of the standard model where the dark sector consists of dark matter particles charged under a $U(1)_x$ gauge symmetry, while a subset of…

High Energy Physics - Phenomenology · Physics 2026-05-11 Wan-Zhe Feng , Jinzheng Li , Pran Nath , Zong-Huan Ye

A large primordial lepton asymmetry is capable of explaining the baryon asymmetry of the Universe (BAU) through suppression of the electroweak sphaleron rates (``sphaleron freeze-in") which can lead to a first-order cosmic QCD transition…

High Energy Physics - Phenomenology · Physics 2023-09-06 Fei Gao , Julia Harz , Chandan Hati , Yi Lu , Isabel M. Oldengott , Graham White

We propose a new mechanism of leptogenesis in which the asymmetries in lepton numbers are produced through the CP-violating oscillations of ``sterile'' (electroweak singlet) neutrinos. The asymmetry is communicated from singlet neutrinos to…

High Energy Physics - Phenomenology · Physics 2008-11-26 E. Kh. Akhmedov , V. A. Rubakov , A. Yu. Smirnov

We propose a mechanism borrowed from string theory which yields a non-singular transition from a phase of Ekpyrotic contraction to the expanding phase of Standard Big Bang cosmology. The same mechanism converts the initial vacuum spectrum…

High Energy Physics - Theory · Physics 2020-04-21 Robert Brandenberger , Ziwei Wang

We propose a framework where a phase transition associated with a gauge symmetry breaking that occurs (not far) above the electroweak scale sets a stage for baryogenesis similar to the electroweak baryogenesis in the Standard Model. A…

High Energy Physics - Phenomenology · Physics 2022-01-11 Kohei Fujikura , Keisuke Harigaya , Yuichiro Nakai , Isaac R. Wang

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

The symmetry breaking of left right symmetric model around few TeV range permits the existence of massive right handed neutrinos or gauge bosons. In this work the decay of lightest right handed neutrinos in a class of minimal left right…

High Energy Physics - Phenomenology · Physics 2020-10-06 Anupam Yadav , Sabeeha Naaz , Jyotsna Singh , R. B. Singh

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

Once a light axionlike scalar field couples to the electroweak gauge bosons, its classical motion during reheating induces an effective chemical potential for the fermion number. In the presence of rapid lepton number (L)-violating…

High Energy Physics - Phenomenology · Physics 2015-07-08 Alexander Kusenko , Kai Schmitz , Tsutomu T. Yanagida

$f(R)$-theories of gravity are reviewed in the context of the so called gravitational baryogenesis. The latter is a mechanism for generating the baryon asymmetry in the Universe, and relies on the coupling between the Ricci scalar curvature…

Astrophysics · Physics 2009-11-11 G. Lambiase , G. Scarpetta

Soft leptogenesis is a scenario in which the cosmic baryon asymmetry is produced from a lepton asymmetry generated in the decays of heavy sneutrinos (the partners of the singlet neutrinos of the seesaw) and where the relevant sources of CP…

High Energy Physics - Phenomenology · Physics 2011-09-07 Chee Sheng Fong , M. C. Gonzalez-Garcia , Enrico Nardi

We study baryogenesis through lepton number violation in left-right symmetric models. In these models the lepton number and CP violating interactions of the triplet higgs scalars can give rise to lepton number asymmetry through…

High Energy Physics - Phenomenology · Physics 2010-11-01 Patrick J. O'Donnell , Utpal Sarkar

We consider a scenario with axions/axion-like particles Chern-Simons gravity coupling, such that gravitational waves can be produced directly from axion wave parametric resonance in the early universe after inflation. This axion gravity…

High Energy Physics - Phenomenology · Physics 2024-04-09 Mingqiu Li , Sichun Sun , Qi-Shu Yan , Zhijie Zhao

The gravitational baryogensis may not generate a sufficient baryon asymmetry in the standard thermal history of the Universe when we take into account the gravitino problem. Hence it has been suggested that anisotropy of the Universe can…

High Energy Physics - Phenomenology · Physics 2016-06-01 Mitsuhiro Fukushima , Shuntaro Mizuno , Kei-ichi Maeda

We present a new type of leptogenesis mechanism based on a two-scalar split-fermions framework. At high temperatures the bulk scalar vacuum expectation values (VEVs) vanish and lepton number is strongly violated. Below some temperature,…

High Energy Physics - Phenomenology · Physics 2014-11-17 Yukinori Nagatani , Gilad Perez

We explore here a new mechanism by which the out of equilibrium decay of heavy gravitinos, followed by possible R-parity violating decays in the Minimal Supersymmetric Standard Model (MSSM) can generate the baryon asymmetry of the universe.…

High Energy Physics - Phenomenology · Physics 2014-02-12 Lawrence M. Krauss , Andrew J. Long , Subir Sabharwal

Some problems of spontaneous and gravitational baryogenesis are discussed. Gravity modification due to the curvature dependent term in gravitational baryogensis scenario is considered. It is shown that the interaction of baryonic fields…

General Relativity and Quantum Cosmology · Physics 2018-12-05 E. V. Arbuzova

We reconsider the GUT-baryogenesis mechanism for generating the baryon asymmetry of the Universe. The baryon asymmetry is produced by the out of equilibrium decay of coloured Higgs bosons at the GUT scale, conserving B-L. If neutrinos are…

High Energy Physics - Phenomenology · Physics 2007-05-23 J. A. Lopez-Perez , N. Rius
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