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Related papers: Formation and Evolution of Antimatter Objects

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We explore in some detail the hypothesis that the generation of a primordial lepton-antilepton asymmetry (Leptogenesis) early on in the history of the Universe is the root cause for the origin of matter. After explaining the theoretical…

High Energy Physics - Phenomenology · Physics 2009-11-11 W. Buchmuller , R. D. Peccei , T. Yanagida

We include an energy term based on Dark Matter (DM) self-annihilation during the cooling and subsequent collapse of the metal-free gas, in halos hosting the formation of the first stars in the Universe. We have found that the feedback…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 E. Ripamonti , F. Iocco , A. Ferrara , R. Schneider , A. Bressan , P. Marigo

The cosmological matter-antimatter asymmetry can arise from the baryon number conserving CP asymmetry in two body decays of heavy particles, when the two final states carry equal and opposite baryon number, and one couples directly or…

High Energy Physics - Phenomenology · Physics 2014-02-12 D. Aristizabal Sierra , Chee Sheng Fong , Enrico Nardi , Eduardo Peinado

We know from experimental high energy physics that whenever matter is created, an equal amount of antimatter is also created. However, we live in a large region of the universe where the antimatter can not constitute more than a very small…

Astrophysics · Physics 2015-08-28 Diego Casadei

We entertain a new paradigm according to which the observed matter-antimatter asymmetry is generated as a large-scale quantum fluctuation over the baryon-symmetric state that occurred during the cosmic inflation.

High Energy Physics - Phenomenology · Physics 2015-07-08 Archil Kobakhidze , Adrian Manning

A scenario for the generation of the baryon asymmetry in the early Universe is proposed in which cosmic string loops, predicted by theories where the baryon and/or lepton numbers are gauged symmetries, collapse during the friction dominated…

High Energy Physics - Phenomenology · Physics 2009-12-30 H. Lew , A. Riotto

The astronomical dark matter is an essential component of the Universe and yet its nature is still unresolved. It could be made of neutral and massive elementary particles which are their own antimatter partners. These dark matter species…

High Energy Astrophysical Phenomena · Physics 2015-06-19 Pierre Salati

We perform a suite of cosmological simulations in the LCDM paradigm of the formation of the first structures in the Universe prior to astrophysical reheating and reionization (15<~z<200). These are the first simulations initialized in a…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Ryan M. O'Leary , Matthew McQuinn

The observational relation between the density of baryon and dark matter in the Universe, $\Omega_{\rm DM}/\Omega_B\simeq 5$, is one of the most difficult problems to solve in modern cosmology. We discuss a scenario that explains this…

High Energy Physics - Phenomenology · Physics 2013-05-30 Kohei Kamada , Masahide Yamaguchi

Current astronomical observations are successfully explained by the present cosmological paradigm based on the concordance model ($\Lambda_0$CDM + Inflation). However, such a scenario is composed of a heterogeneous mix of ingredients for…

General Relativity and Quantum Cosmology · Physics 2018-08-29 J. A. S Lima , Douglas Singleton

We explore the viability of a boson dark matter candidate with an asymmetry between the number densities of particles and antiparticles. A simple thermal field theory analysis confirms that, under certain general conditions, this component…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-27 Anthony Aguirre , Alberto Diez-Tejedor

We introduce the hypothesis that the matter content of the universe can be a product of the decay of primordial vector bosons. The effect of the intensive cosmological creation of these primordial vector $W, ~Z $ bosons from the vacuum is…

High Energy Physics - Theory · Physics 2016-09-06 D. Blaschke , V. Pervushin , D. Proskurin , S. Vinitsky , A. Gusev

We present results of cosmological N-body hydrodynamic chemistry simulations of primordial structure growth and evolution in a scenario with warm dark matter (WDM) having a mass of 3 keV (thermal relic) and compare with a model consisting…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Umberto Maio , Matteo Viel

The first stars in the universe form inside $\sim 10^6 M_\odot$ dark matter (DM) haloes whose initial density profiles are laid down by gravitational collapse in hierarchical structure formation scenarios. During the formation of the first…

Astrophysics · Physics 2011-02-11 Katherine Freese , Paolo Gondolo , J. A. Sellwood , Douglas Spolyar

We present here studies of collapse of purely baryonic Population III objects with masses ranging from $10M_\odot$ to $10^6M_\odot$. A spherical Lagrangian hydrodynamic code has been written to study the formation and evolution of the…

Astrophysics · Physics 2009-10-30 S. R. Oliveira , O. D. Miranda , J. C. N. de Araujo , R. Opher

-The favored Big Bang concept is that the original symmetry was skewed, the universe now being all matter, all antimatter having annihilated. -The mechanism of matter/antimatter annihilation is analyzed. A total annihilation of original…

General Physics · Physics 2011-11-09 Roger Ellman

Non-conservation of dark matter can lead to late-time cosmic acceleration. This mechanism is known as the matter creation theory and this replaces the need of dark energy and modified gravity theories. We consider a two-fluid system…

General Relativity and Quantum Cosmology · Physics 2025-12-02 Sudip Halder , Jaume de Haro , Supriya Pan , Tapan Saha , Subenoy Chakraborty

We have studied big bang nucleosynthesis in the presence of regions of antimatter. Depending on the distance scale of the antimatter region, and thus the epoch of their annihilation, the amount of antimatter in the early universe is…

Astrophysics · Physics 2009-10-31 Hannu Kurki-Suonio , Elina Sihvola

We study the gravitational collapse of compact objects in the Brane-World. We begin by arguing that the regularity of the five-dimensional geodesics does not allow the energy-momentum tensor of matter on the brane to have (step-like)…

High Energy Physics - Theory · Physics 2009-11-10 Roberto Casadio , Cristiano Germani

Axions and axion-like particles are compelling candidates for the missing dark matter of the universe. As they undergo gravitational collapse, they can form compact objects such as axion stars or even black holes. In this paper, we study…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-17 James Y. Widdicombe , Thomas Helfer , David J. E. Marsh , Eugene A. Lim