scholarly journals Lepton and Baryon Number Asymmetry of the Universe and Primordial Nucleosynthesis

1988 ◽  
Vol 80 (3) ◽  
pp. 468-476 ◽  
Author(s):  
N. Terasawa ◽  
K. Sato
Keyword(s):  
Baryon Number ◽  
Primordial Nucleosynthesis ◽  
Baryon Number Asymmetry ◽  
The Universe

scholarly journals AFFLECK–DINE LEPTOGENESIS IN THE RADIATIVE NEUTRINO MASS MODEL

2011 ◽  
Vol 26 (06) ◽  
pp. 995-1009 ◽  
Author(s):  
H. HIGASHI ◽  
T. ISHIMA ◽  
D. SUEMATSU
Keyword(s):  
Dark Matter ◽  
Neutrino Mass ◽  
Baryon Number ◽  
Lepton Number ◽  
Neutrino Masses ◽  
Alternative Possibility ◽  
Mass Model ◽  
Neutrino Mass Models ◽  
Baryon Number Asymmetry ◽  
The Universe

Radiative neutrino mass models have interesting features, which make it possible to relate neutrino masses to the existence of dark matter. However, the explanation of the baryon number asymmetry in the universe seems to be generally difficult as long as we suppose leptogenesis based on the decay of thermal right-handed neutrinos. Since right-handed neutrinos are assumed to have masses of O(1) TeV in these models, they are too small to generate the sufficient lepton number asymmetry. Here we consider Affleck–Dine leptogenesis in a radiative neutrino mass model by using a famous flat direction LHu as an alternative possibility. The constraint on the reheating temperature could be weaker than the ordinary models. The model explains all the origin of the neutrino masses, the dark matter, and also the baryon number asymmetry in the universe.

scholarly journals Freeze-in Dirac neutrinogenesis: thermal leptonic CP asymmetry

2020 ◽  
Vol 80 (12) ◽  
Author(s):  
Shao-Ping Li ◽  
Xin-Qiang Li ◽  
Xin-Shuai Yan ◽  
Ya-Dong Yang
Keyword(s):  
Thermal Equilibrium ◽  
Charged Lepton ◽  
Baryon Number ◽  
Lepton Number ◽  
Cp Asymmetry ◽  
Mixing Angle ◽  
Neutrino Sector ◽  
The Right ◽  
Baryon Number Asymmetry ◽  
The Universe

AbstractWe present a freeze-in realization of the Dirac neutrinogenesis in which the decaying particle that generates the lepton-number asymmetry is in thermal equilibrium. As the right-handed Dirac neutrinos are produced non-thermally, the lepton-number asymmetry is accumulated and partially converted to the baryon-number asymmetry via the rapid sphaleron transitions. The necessary CP-violating condition can be fulfilled by a purely thermal kinetic phase from the wavefunction correction in the lepton-doublet sector, which has been neglected in most leptogenesis-based setup. Furthermore, this condition necessitates a preferred flavor basis in which both the charged-lepton and neutrino Yukawa matrices are non-diagonal. To protect such a proper Yukawa structure from the basis transformations in flavor space prior to the electroweak gauge symmetry breaking, we can resort to a plethora of model buildings aimed at deciphering the non-trivial Yukawa structures. Interestingly, based on the well-known tri-bimaximal mixing with a minimal correction from the charged-lepton or neutrino sector, we find that a simultaneous explanation of the baryon-number asymmetry in the Universe and the low-energy neutrino oscillation observables can be attributed to the mixing angle and the CP-violating phase introduced in the minimal correction.

scholarly journals Catalyzed baryogenesis

2021 ◽  
Vol 2021 (10) ◽  
Author(s):  
Yang Bai ◽  
Joshua Berger ◽  
Mrunal Korwar ◽  
Nicholas Orlofsky
Keyword(s):  
Standard Model ◽  
Equilibrium Condition ◽  
Direct Detection ◽  
Outer Wall ◽  
Baryon Number ◽  
Baryon Asymmetry ◽  
The Standard Model ◽  
Large Ball ◽  
Baryon Number Asymmetry ◽  
Ball Mass

Abstract A novel mechanism, “catalyzed baryogenesis”, is proposed to explain the observed baryon asymmetry in our universe. In this mechanism, the motion of a ball-like catalyst provides the necessary out-of-equilibrium condition, its outer wall has CP-violating interactions with the Standard Model particles, and its interior has baryon number violating interactions. We use the electroweak-symmetric ball model as an example of such a catalyst. In this model, electroweak sphalerons inside the ball are active and convert baryons into leptons. The observed baryon number asymmetry can be produced for a light ball mass and a large ball radius. Due to direct detection constraints on relic balls, we consider a scenario in which the balls evaporate, leading to dark radiation at testable levels.

THERMAL LEPTOGENESIS IN SO(10) GUT

2008 ◽  
Vol 23 (17n20) ◽  
pp. 1464-1469 ◽  
Author(s):  
XIANGDONG JI
Keyword(s):  
Thermal Equilibrium ◽  
Baryon Number ◽  
Lepton Number ◽  
Grand Unification ◽  
The Universe ◽  
Lepton Number Violating

I discuss the possibility of generating the observed baryon number in the universe through the lepton-number violating processes in a class of SO(10) grand unification theories. The key ingredient is the CP violating decay of the heavy right-handed neutrinos out of thermal equilibrium.

LEE–YANG FORCE, GAUGE SYMMETRY AND "DARK ENERGY"

2005 ◽  
Vol 20 (37) ◽  
pp. 2855-2859 ◽  
Author(s):  
JONG-PING HSU
Keyword(s):  
Dark Energy ◽  
Gauge Symmetry ◽  
Baryon Number ◽  
Lepton Number ◽  
Repulsive Force ◽  
Baryonic Matter ◽  
Gauge Invariant ◽  
Einstein's Equation ◽  
Expansion Of The Universe ◽  
The Universe

In 1955, Lee and Yang discussed a new massless gauge field based on the established conservation of baryon number. They predicted the existence of a repulsive force between baryonic matter, just as the conservation of electron–lepton number was later shown to imply the existence of a repulsive force between electrons. Although Eötvös experiments showed the force to be undetectably small at that time, such a force may be related to the dark-energy-induced acceleration of the expansion of the universe. If the gauge invariant Lagrangian involves a spacetime derivative of the field strength, the resultant potential has properties similar to that of the "dark energy" implied by the cosmological constant in the Einstein's equation.

scholarly journals A New Left-Right Symmetry Model

2020 ◽  
Vol 2020 ◽  
pp. 1-8
Author(s):  
Apriadi Salim Adam ◽  
Akmal Ferdiyan ◽  
Mirza Satriawan
Keyword(s):  
Quantum Number ◽  
New Left ◽  
Symmetry Transformation ◽  
Baryon Number ◽  
Big Bang ◽  
Majorana Neutrino ◽  
Symmetry Model ◽  
Baryon Number Asymmetry ◽  
The Big Bang ◽  
R Symmetry

We propose a new L-R symmetry model where the L-R symmetry transformation reverses both the L-R chirality and the local quantum number. We add to the model a global quantum number F whose value is one for fermions (minus one for antifermion) and vanishes for bosons. For each standard model (SM) particle, we have the corresponding L-R dual particle whose mass is very large and which should have decayed at the current low energy level. Due to the global quantum number F, there is no Majorana neutrino in the model but a Dirac seesaw mechanism can still occur and the usual three active neutrino oscillation can still be realized. We add two leptoquarks and their L-R duals, for generating the baryon number asymmetry and for facilitating the decay of the L-R dual particles. The decay of the L-R dual particles will produce a large entropy to the SM sector and give a mechanism for avoiding the big bang nucleosynthesis constraint.

scholarly journals A New Measurement of the Geometry of Space

1987 ◽  
Vol 124 ◽  
pp. 217-221
Author(s):  
Edwin D. Loh
Keyword(s):  
Big Bang ◽  
Recent Measurement ◽  
Density Parameter ◽  
Confidence Limits ◽  
Dimensionless Form ◽  
Primordial Nucleosynthesis ◽  
Geometrical Effects ◽  
Age Of The Universe ◽  
The Universe ◽  
Inflationary Models

This paper discusses the recent measurement of the number of galaxies vs. redshift and flux and presents new results pertaining to the two dimensionless geometrical quantities that describe the geometry of the conventional big-bang cosmology, the density parameter Ω and the dimensionless form λ = Λ/(3H02) of the cosmological constant. In contrast to the classical redshift-magnitude test as applied to the brightest galaxies in clusters, this new method is able to separate the effects of evolution from geometrical effects and is therefore able to measure the geometry of space. The 95% confidence limits are Ω - λ = 0.9−0 5+0 7 and −1.5 < Ω + λ < 7.1. The principal conclusions are these: (1) For both λ = 0 and inflationary models of the universe, this measurement and primordial nucleosynthesis imply a large density of nonbaryonic matter. (2) Hubble's constant H0 and the age of the universe τ are constrained by 0.60 < H0τ < 0.88 (95% confidence).

scholarly journals Photon Creation in the Universe and Primordial Nucleosynthesis

2000 ◽  
Vol 198 ◽  
pp. 113-115
Author(s):  
J.A. S. Lima ◽  
J. S. Alcaniz ◽  
J. Santos ◽  
R. Silva
Keyword(s):  
Irreversible Process ◽  
Big Bang ◽  
Radiation Temperature ◽  
Thermodynamic Approach ◽  
Phenomenological Parameter ◽  
Primordial Nucleosynthesis ◽  
Stringent Constraint ◽  
The Universe ◽  
Creation Rate

In hot big bang cosmologies, the irreversible process of continous photon creation may phenomenologically be described through a thermodynamic approach. In these models, the radiation temperature law depends on a phenomenological parameter β which is closely related to the photon creation rate. It is shown that a stringent constraint on the value of this parameter is imposed from primordial nucleosynthesis.

scholarly journals Evidence of the big fix

2014 ◽  
Vol 29 (17) ◽  
pp. 1450099 ◽  
Author(s):  
Yuta Hamada ◽  
Hikaru Kawai ◽  
Kiyoharu Kawana
Keyword(s):  
Maximum Entropy Principle ◽  
Vacuum Expectation ◽  
Vacuum Expectation Value ◽  
Baryon Number ◽  
Quark Masses ◽  
Atomic Nuclei ◽  
The Standard Model ◽  
Entropy Principle ◽  
Fundamental Law ◽  
The Universe

We give an evidence of the Big Fix. The theory of wormholes and multiverse suggests that the parameters of the Standard Model are fixed in such a way that the total entropy at the late stage of the universe is maximized, which we call the maximum entropy principle. In this paper, we discuss how it can be confirmed by the experimental data, and we show that it is indeed true for the Higgs vacuum expectation value vh. We assume that the baryon number is produced by the sphaleron process, and that the current quark masses, the gauge couplings and the Higgs self-coupling are fixed when we vary vh. It turns out that the existence of the atomic nuclei plays a crucial role to maximize the entropy. This is reminiscent of the anthropic principle, however it is required by the fundamental law in our case.

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