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Related papers: Cosmology in a non-standard statistical background

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The time evolution of cosmological parameters in early Universe at the deconfinement transition is studied by an equation of state (EoS) which takes into account the finite baryon density and the background magnetic field. The non…

High Energy Physics - Phenomenology · Physics 2015-09-30 Paolo Castorina , Vincenzo Greco , Salvatore Plumari

In the standard approach to studying cosmological structure formation, the overall expansion of the Universe is assumed to be homogeneous, with the gravitational effect of inhomogeneities encoded entirely in a Newtonian potential. A topic…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-20 William E. East , Radosław Wojtak , Tom Abel

We study the consequences of new long-range forces between neutrinos on cosmic scales. If these forces are a few orders of magnitude stronger than gravity, they can induce perturbation instability in the non-relativistic cosmic neutrino…

High Energy Physics - Phenomenology · Physics 2025-03-28 David E. Kaplan , Xuheng Luo , Surjeet Rajendran

Primordial nucleosynthesis remains as one of the pillars of modern cosmology. It is the testing ground upon which many cosmological models must ultimately rest. It is our only probe of the universe during the important radiation-dominated…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-20 Grant J. Mathews , Motohiko Kusakabe , Toshitaka Kajino

With the era of precision cosmology upon us, and upcoming surveys expected to further improve the precision of our observations below the percent level, ensuring the accuracy of our theoretical cosmological model is of the utmost…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-30 Hayley J. Macpherson

Gravitational particle production has been investigated by using Einstein's gravitational field equations in the presence of a cosmological constant. To study the mechanism of particle creation, the Universe has been considered as a…

General Relativity and Quantum Cosmology · Physics 2020-04-07 Z. Safari , B. Malekolkalami , H. Moshafi

We investigate the joint effect of the cosmological phase transitions, thermal light dark matter, and the lepton asymmetry on the big bang nucleosynthesis and cosmic microwave background. We find that all of them can modify the predictions…

High Energy Physics - Phenomenology · Physics 2023-10-06 Shihao Deng , Ligong Bian

We study cosmological perturbations in the context of an interacting dark energy model, in which the cosmological term decays linearly with the Hubble parameter, with concomitant matter production. A previous joint analysis of the…

Astrophysics · Physics 2008-11-26 H. A. Borges , S. Carneiro , J. C. Fabris , C. Pigozzo

The primordial abundance of deuterium produced during Big Bang Nucleosynthesis (BBN) depends sensitively on the universal ratio of baryons to photons, an important cosmological parameter probed independently by the Cosmic Microwave…

Astrophysics of Galaxies · Physics 2015-05-13 Gary Steigman

The cosmological dynamics in the early universe are investigated to explore the possibility of the sign reversal of the Hubble parameter as a key feature of non-singular bouncing cosmological solutions in higher-order torsion gravity. The…

General Relativity and Quantum Cosmology · Physics 2026-03-31 Adnan Malik , Aimen Rauf , Kazuharu Bamba , Wenbin Lin , Fatemah Mofarreh

The appearance of strangeness in the form of hyperons within the inner core of neutron stars is expected to affect its detectable properties such as its global structure or gravitational wave emission. In this work, we explore the parameter…

High Energy Astrophysical Phenomena · Physics 2023-12-19 Suprovo Ghosh , Bikram Keshari Pradhan , Debarati Chatterjee , Jürgen Schaffner-Bielich

We explore the consequences of allowing non-Hermitian structures in quantum cosmology by extending the Wheeler DeWitt framework beyond strictly Hermitian dynamics. Using a controlled semiclassical reduction, we show how anti Hermitian…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-06 Oem Trivedi , Alfredo Gurrola

We study the evolution of cosmological perturbations, using a hybrid approximation scheme which upgrades the weak-field limit of Einstein's field equations to account for post-Newtonian scalar and vector metric perturbations and for…

Astrophysics · Physics 2007-05-23 Carmelita Carbone , Sabino Matarrese

The combination of detections of anisotropy in the Cosmic Microwave Background radiation and observations of the large-scale distribution of galaxies probes the primordial density fluctuations of the universe on spatial scales varying by…

Astrophysics · Physics 2008-11-26 Eric Gawiser , Joseph Silk

In this work we revisit the question of whether Cosmology can be made compatible with scenarios with light sterile neutrinos, as invoked to explain the SBL anomalies, in the presence of self-interaction among sterile neutrinos mediated by…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-07 Ningqiang Song , M. C. Gonzalez-Garcia , Jordi Salvado

We calculate and display the primordial light-element abundances as a function of a neutrino degeneracy parameter \xi common to all flavors. It is the only unknown parameter characterizing the thermal medium at the primordial…

Astrophysics · Physics 2009-11-11 Pasquale D. Serpico , Georg G. Raffelt

Axions with mass greater than 0.7 eV are excluded by cosmological precision data because they provide too much hot dark matter. While for masses above 20 eV the axion lifetime drops below the age of the universe, we show that the…

High Energy Physics - Phenomenology · Physics 2015-03-17 Davide Cadamuro , Steen Hannestad , Georg Raffelt , Javier Redondo

When combining cosmological and oscillations results to constrain the neutrino sector, the question of the propagation of systematic uncertainties is often raised. We address this issue in the context of the derivation of an upper bound on…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-25 F. Couchot , S. Henrot-Versillé , O. Perdereau , S. Plaszczynski , B. Rouillé d'Orfeuil , M. Spinelli , M. Tristram

Big bang nucleosynthesis (BBN) and the cosmic microwave background (CMB) have a long history together in the standard cosmology. The general concordance between the predicted and observed light element abundances provides a direct probe of…

Astrophysics · Physics 2009-11-10 Richard H. Cyburt

We derive constraints on the strength of a new intermediate range interaction that couples to baryon number from primordial nucleosynthesis yields. The nucleosysnthesis limits here used arise from matching observations and predictions of…

High Energy Physics - Phenomenology · Physics 2009-10-31 O. Bertolami , F. M. Nunes
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