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Related papers: Parity-violation in bouncing cosmology

200 papers

Supernovae provide a unique opportunity for large scale parity violation because they are dominated by neutrinos. We calculate the parity violating asymmetry A of neutrino emission in a strong magnetic field. We assume the neutrinos…

Astrophysics · Physics 2009-10-30 C. J. Horowitz , Gang Li

Pseudoscalar or pseudovector cosmic fields, that serve as a source of parity ($\mathcal{P}$) violation, are invoked in different models for cold dark matter or in the standard model extension that allows for Lorentz invariance violation. A…

Chemical Physics · Physics 2020-09-23 Konstantin Gaul , Mikhail G. Kozlov , Timur A. Isaev , Robert Berger

The parity-violating asymmetry, accounting for the vector and axial-vector vertex plus self-energy correction as well as for vacuum polarization, is calculated nonperturbatively by solving the corresponding Dirac equation for the electronic…

Nuclear Theory · Physics 2026-04-27 Xavier Roca-Maza , D. H. Jakubassa-Amundsen

Parity violation in the early universe holds great promise for uncovering new physics. In particular, the primordial scalar four-point correlation function is allowed to develop a parity-violating component when massive spinning particles…

High Energy Physics - Theory · Physics 2023-08-23 Sadra Jazayeri , Sébastien Renaux-Petel , Xi Tong , Denis Werth , Yuhang Zhu

In this study we demonstrate the interacting teleparallel gravity models, to describe the matter bounce scenario. We discussed two interacting models and find both are suitable choice to describe the bouncing phenomena. The co-moving Hubble…

General Relativity and Quantum Cosmology · Physics 2025-09-03 S. A. Kadam , A. S. Agrawal

We consider bouncing cosmologies in which an ekpyrotic contraction phase with w >> 1 is followed by a bouncing phase with w < -1 that violates the null energy condition. The bouncing phase, induced by ghost condensation, is designed to…

High Energy Physics - Theory · Physics 2013-05-29 BingKan Xue , Paul J. Steinhardt

Bouncing cosmologies, suggested by String/M-theory, may provide an alternative to standard inflation to account for the origin of inhomogeneities in our universe. The fundamental question regards the correct way to evolve the scalar…

High Energy Physics - Theory · Physics 2009-11-11 V. Bozza

It is well known that one can use B -> pi pi decays to probe the CP-violating phase \alpha. In this paper we show that these same decays can be used to search for new physics. This is done by comparing two weak phases which are equal in the…

High Energy Physics - Phenomenology · Physics 2009-10-31 D. London , N. Sinha , R. Sinha

The advantage of searching for violation of Time Reversal Invariance in neutron induced reactions using relative measurements of Time and Parity violating effects is discussed. This approach gives the enhancement of $T$-violating effects by…

Nuclear Theory · Physics 2016-11-23 Vladimir Gudkov

In supersymmetric scenarios with broken R-parity, baryon number violating sparticle decays become possible. In order to search for such decays, a good understanding of expected event properties is essential. We here develop a complete…

High Energy Physics - Phenomenology · Physics 2009-12-15 T. Sjöstrand , P. Z. Skands

We study how a cosmological bounce with a Type IV singularity at the bouncing point, can be generated by a classical vacuum $F(G)$ gravity. We focus our investigation on the behavior of the vacuum $F(G)$ theory near the Type IV singular…

General Relativity and Quantum Cosmology · Physics 2015-12-23 V. K. Oikonomou

The violation of spacetime symmetries provides a promising candidate signal for underlying physics, possibly arising at the Planck scale. This talk gives an overview over various aspects in the field, including some mechanisms for Lorentz…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Ralf Lehnert

A bouncing cosmology with an initial matter-dominated phase of contraction during which scales which are currently probed with cosmological observations exit the Hubble radius provides a mechanism alternative to inflation for producing a…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-20 Robert H. Brandenberger

Preheating describes the stage of rapidly depositing the energy of cosmological scalar field into excitations of other light fields. This stage is characterized by exponential particle production due to the parametric resonance. We study…

High Energy Physics - Theory · Physics 2015-03-19 Yi-Fu Cai , Robert Brandenberger , Xinmin Zhang

Being able to reliably track perturbations across bounces and turnarounds in cyclic and bouncing cosmology lies at the heart of being able to compare the predictions of these models with the Cosmic Microwave Background observations. This…

General Relativity and Quantum Cosmology · Physics 2016-03-23 Tirthabir Biswas , Riley Mayes , Colleen Lattyak

The singularity and inflationary problems have posed significant challenges for understanding the universe's origin and evolution. Bouncing cosmology has emerged as a promising alternative to standard cosmological models, offering a…

General Relativity and Quantum Cosmology · Physics 2025-07-28 A. Zhadyranova , M. Koussour , V. Zhumabekova , N. Zhusupova , S. Muminov , J. Rayimbaev

Nonlinear dynamics of wave packets in two-dimensional parity-time-symmetric optical lattices near the phase-transition point are analytically studied. A novel fourth-order equation is derived for the envelope of these wave packets. A…

Optics · Physics 2016-04-13 Sean Nixon , Jianke Yang

Bouncing cosmologies, while offering a compelling alternative to inflationary models, face challenges from the growth of vector perturbations during the contracting phase. While linear vector instabilities can be avoided with specific…

General Relativity and Quantum Cosmology · Physics 2025-09-26 Mian Zhu , Chao Chen

We study semi-classical particle production in non-singular bouncing cosmologies by employing the Unruh-DeWitt model of a particle detector propagating in this class of spacetimes. The scale factor for the bouncing cosmology is derived…

General Relativity and Quantum Cosmology · Physics 2025-02-14 Aindriú Conroy , Peter Taylor

Scenario of a bouncing universe is one of the most active area of research to arrive at singularity free cosmological models. Different proposals have been suggested to avoid the so called 'big bang' singularity through the quantum aspect…

General Relativity and Quantum Cosmology · Physics 2022-10-26 Indrani Banerjee , Tanmoy Paul , Soumitra SenGupta