Related papers: Induced gravity and cosmological principle
Cosmology is built on a relativistic understanding of gravity, where the geometry of the Universe is dynamically determined by matter and energy. In the cosmological concordance model, gravity is described by General Relativity, and it is…
The present work deals with a cosmological model having particle creation mechanism in the framework of irreversible thermodynamics. In the second order non-equilibrium thermodynamical prescription, the particle creation rate is treated as…
A growing number of studies is being devoted to the identification of plausible quantum properties of spacetime which might give rise to observably large effects. The literature on this subject is now relatively large, including studies in…
In this paper we present a cosmological model arising from a non-conservative gravitational theory proposed in [PRD 95, 101501(R) (2017)]. The novel feature where comparing with previous implementations of dissipative effects in gravity is…
A perfect fluid, spatially flat cosmology in a $f(T)$ model, derived from a recently proposed general Born-Infeld type theory of gravity is studied. Four dimensional cosmological solutions are obtained assuming the equation of state…
We consider a spatially flat Friedmann-Lemaitre-Robertson-Walker space time and investigate the second law and the generalized second law of thermodynamics for apparent horizon in generalized modified Gauss Bonnet theory of gravity (whose…
Super-high energy corpuscular and gamma rays as well as cosmic high--power density sources are hard to explain in a galaxy model framework. Attempts to include some of those phenomena in the Standard Cosmological Model also encounter…
Modern particle physics and cosmology support the idea that a background of invisible material pervades the whole universe, and identify in the cosmic vacuum the ultimate source of matter-energy, both seen and unseen. Within the framework…
The unified theory of string and two-dimensional quantum gravity is considered. The action for two-dimensional gravity is choosen in a well-known induced form and thus gravity posesses it's oun nontrivial dynamics even on the classical…
It is very likely that the quantum description of spacetime is quite different from what we perceive at large scales, $l\gg (G\hbar/c^3)^{1/2}$. The long wave length description of spacetime, based on Einstein's equations, is similar to the…
The common nature of dark matter and dark energy is argued in [1] based on the approach that the cosmological constant \Lambda enters the weak-field General Relativity following from Newton theorem on the "sphere-point mass" equivalency…
There are many theories of quantum gravity, depending on asymptotic boundary conditions, and the amount of supersymmetry. The cosmological constant is one of the fundamental parameters that characterize different theories. If it is…
In general relativity, a gravitational horizon (more commonly known as the "apparent horizon") is an imaginary surface beyond which all null geodesics recede from the observer. The Universe has an apparent (gravitational) horizon, but…
Renormalization group (RG) improved cosmologies based upon a RG trajectory of Quantum Einstein Gravity (QEG) with realistic parameter values are investigated using a system of cosmological evolution equations which allows for an…
We present a bounce universe in modified $f(Q,C)$ gravity considering linear as well as exponential form of gravity. Bounce cosmological models are introduced to remove the singularity problem of the early universe. A new quadratic boundary…
One obtains a Maxwell-like structure of gravitation by applying the weak-field approximation to the well accepted theory of general relativity or by extending Newton's laws to time-dependent systems. This splits gravity in two parts, namely…
We study the approach in which independent variables describing gravity are functions of the space-time embedding into a flat space of higher dimension. We formulate a canonical formalism for such a theory in a form, which requires imposing…
Quantum gravity places entirely new challenges on the formulation of a consistent theory as well as on an extraction of potentially observable effects. Quantum corrections due to the gravitational field are commonly expected to be tiny…
Starting from first principles and general assumptions Newton's law of gravitation is shown to arise naturally and unavoidably in a theory in which space is emergent through a holographic scenario. Gravity is explained as an entropic force…
Within our recent thermodynamic model of gravity the dark energy is identified with the energy of collective gravitational interactions of all particles in the universe, which is missing in the standard treatments. For a simple model…