Related papers: Gravitational Baryogenesis
The simplest explanation for early time acceleration (inflation) and the late time acceleration indicated by recent data is that they have a common origin. We investigate another generic cosmological implication of this possiblity, that the…
The baryon-antibaryon asymmetry (excess of matter over antimatter in our Universe), indicated by observational data from the Cosmic Microwave Background anisotropies, predictions of primordial Nucleosynthesis, and the absence of intense…
The dynamics of a gravitational wave propagating through a cosmic gauge field are dramatically different than in vacuum. We show that a gravitational wave acquires an effective mass, is birefringent, and its normal modes are a linear…
It is shown that quantum fluctuations due to a nontrivial gravitational background in the flat radiation dominated universe can play an important cosmological role generating nonvanishing cosmological global charge, e.g. baryon number,…
The influence of space-time torsion on gravitational interaction at cosmological and astrophysical scales is discussed within the framework of gauge gravitation theory in Riemann-Cartan space-time. It is shown that the interaction of the…
I present a simple scheme for the treatment of gravitational interactions on galactic scales. In analogy to known mechanisms of quantum field theory, I assume ad hoc that gravitation is mediated by virtual exchange particles - gravitons -…
The gravitational Chern-Simons term coupled to an evolving axion is known to generate lepton number through the gravitational anomaly. We examine this leptogenesis scenario in the presence of the Gauss-Bonnet term over and above the…
We investigate the generation of the observed baryon asymmetry of the Universe within the framework of $f(T,T_{G})$ gravity, where $T$ is the torsion scalar and $T_{G}$ denotes its teleparallel Gauss--Bonnet counterpart. Two illustrative…
We consider modified theories of gravity with a direct coupling between matter and geometry, denoted by an arbitrary function in terms of the Ricci scalar. Due to such a coupling, the matter stress tensor is no longer conserved and there is…
We study a concrete realization of gravitational baryogenesis in which a small bulk-viscous deformation of an otherwise radiation-dominated early universe generates a sign-definite curvature source. The key point is thermodynamic…
We propose a gravitational theory in which the effective Lagrangian of the gravitational field is given by an arbitrary function of the Ricci scalar, the trace of the matter energy-momentum tensor, and the contraction of the Ricci tensor…
Based on a study of {\it charge,} (C), {\it parity} (P) and {\it time reversal} (T) symmetries we show how a CP violating network of defects in the early Universe may bias baryon number production. A static network, even though it violates…
We explore the gravitational baryogenesis paradigm in the homogeneous and isotropic cosmology of generalized coupling gravity and, in particular, of the so-called Minimal Exponential Measure Model (MEMe). We show that, also in this theory,…
Our present understanding of the universe requires the existence of dark matter and dark energy. We describe here a natural mechanism that could make exotic dark matter and possibly dark energy unnecessary. Graviton-graviton interactions…
Loop Quantum Cosmology is an appealing quantum completion of classical cosmology, which brings along various theoretical features which in many cases offer remedy or modify various classical cosmology aspects. In this paper we address the…
We consider the possibility of a gravitationally induced particle production through the mechanism of a nonminimal curvature-matter coupling. An interesting feature of this gravitational theory is that the divergence of the energy-momentum…
The origin of matter domination in the Universe is one of the most exciting open puzzles in particle physics and cosmology. Despite many theoretical developments, the actual reason behind baryon-antibaryon asymmetry is still unknown. Our…
We consider QCD axion models where the Peccei-Quinn symmetry is badly broken by a larger amount in the past than in the present, in order to avoid the axion isocurvature problem. Specifically we study supersymmetric axion models where the…
A model of baryogenesis is introduced where our usual visible Universe is a 3-brane coevolving with a hidden 3-brane in a multidimensional bulk. The visible matter and antimatter sectors are naturally coupled with the hidden matter and…
We consider the complex inflaton field with a CP asymmetric term for its potential. This CP asymmetric term produces the global charge of the inflaton after inflation. With the assignment of the baryon number to the inflaton, the baryon…