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Cosmological consequences of the Poincare-Weyl gauge theory of gravity are considered. A generalized cosmological constant depending from the Dirac scalar field is introduced. The stage of a super-early (Harrison-Zel'dovich) scale invariant…

General Relativity and Quantum Cosmology · Physics 2020-01-17 Olga V. Babourova , Boris N. Frolov

An analysis of null geodesics in Schwarzschild de Sitter space is presented with special attention to their global `bending angles', local measurable angles, and the involvement of the cosmological constant. We make use of a general…

General Relativity and Quantum Cosmology · Physics 2016-09-19 Dmitri Lebedev , Kayll Lake

The Universe is neither homogeneous nor isotropic, but it is close enough that we can reasonably approximate it as such on suitably large scales. The inflationary-$\Lambda$-Cold Dark Matter ($\Lambda$CDM) concordance cosmology builds on…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-08 Stefano Anselmi , Matthew F. Carney , John T. Giblin , Saurabh Kumar , James B. Mertens , Marcio ODwyer , Glenn D. Starkman , Chi Tian

String theory has no parameter except the string scale, so a dynamically compactified solution to 4 dimensional spacetime should determine both the Planck scale and the cosmological constant $\Lambda$. In the racetrack K\"ahler uplift flux…

High Energy Physics - Theory · Physics 2019-10-25 Stefano Andriolo , Shing Yan Li , S. H. Henry Tye

In this paper, the suggested similarity between micro and macro-cosmos is extended to quantum behavior, postulating that quantum mechanics, like general relativity and classical electrodynamics, is invariant under discrete scale…

General Relativity and Quantum Cosmology · Physics 2009-10-30 Saulo Carneiro

The k=0 Friedmann Lemaitre Robertson Walker model with a positive cosmological constant and a massless scalar field is analyzed in detail. If one uses the scalar field as relational time, new features arise already in the Hamiltonian…

General Relativity and Quantum Cosmology · Physics 2015-06-03 Tomasz Pawlowski , Abhay Ashtekar

Massive gravity provides a natural solution for the dark energy problem of cosmology and is also a candidate for resolving the dark matter problem. I demonstrate that, assuming reasonable scaling relations, massive gravity can provide for…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-09 Sascha Trippe

We build a minimal extension of General Relativity in which Newton's gravitational coupling, $G$, the speed of light, $c$, and the cosmological constant, $\Lambda$, are spacetime variables. This is done while satisfying the contracted…

General Relativity and Quantum Cosmology · Physics 2017-04-27 Guilherme Franzmann

The \HOmega\ diagram is resurrected to dramatically illustrate the nature of the key problems in physical cosmology today and the role that nuclear physics plays in many of them. In particular it is noted that the constraints on \OmegaB\…

Astrophysics · Physics 2014-10-13 Craig J. Copi , David N. Schramm

The equations of motion describing all physical systems, except gravity, remain invariant if a constant is added to the Lagrangian. In the conventional approach, gravitational theories break this symmetry exhibited by all other physical…

General Relativity and Quantum Cosmology · Physics 2015-12-22 T. Padmanabhan

We have found that the hierarchial problems appearing in cosmology is a manifestation of the quantum nature of the universe. The universe is still described by the same formulae that once hold at Planck's time. The universe is found to be…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Arbab I. Arbab

Three theoretical criteria for gravitational theories beyond general relativity are considered: obtaining the cosmological constant as an integration constant, deriving the energy conservation law as a consequence of the field equations,…

General Relativity and Quantum Cosmology · Physics 2023-08-17 Junpei Harada

We study the classical and quantum cosmology of a universe in which the matter source is a massive Dirac spinor field and consider cases where such fields are either free or self-interacting. We focus attention on the spatially flat…

General Relativity and Quantum Cosmology · Physics 2009-11-11 B. Vakili , S. Jalalzadeh , H. R. Sepangi

It is shown that Einstein field equations give two solutions for cosmology. The first one is the standard well known representative of the present status of cosmology. We identify it with the local point of view of a flat Universe with the…

General Physics · Physics 2008-01-04 Antonio Alfonso-Faus

A simple model of an atom interacting with the quantized electromagnetic field is studied. The atom has a finite mass $m$, finitely many excited states and an electric dipole moment, $\vec{d}_0 = -\lambda_{0} \vec{d}$, where $\| d^{i}\| =…

Mathematical Physics · Physics 2015-05-20 Miguel Ballesteros , Jérémy Faupin , Jürg Fröhlich , Baptiste Schubnel

We suggest a new perspective on the Cosmological Constant Problem by scrutinizing its standard formulation. In classical and quantum mechanics without gravity, there is no definition of the zero point of energy. Furthermore, the Casimir…

High Energy Physics - Theory · Physics 2014-09-25 Denis Bernard , André LeClair

The tensions between the values of Hubble constant obtained from the early and the late Universe data pose a significant challenge to modern cosmology. Possible modifications of the flat homogeneous isotropic cosmological {\Lambda}CDM model…

Cosmology and Nongalactic Astrophysics · Physics 2021-10-14 S. L. Parnovsky

A model is suggested to unify the Einstein GR and Dirac Cosmology. There is one adjusted parameter $b_2$ in our model. After adjusting the parameter $b_2$ in the model by using the supernova data, we have calculated the gravitational…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Cheng-Gang Shao , Jianyong Shen , Bin Wang , Ru-Keng Su

A new approach to the cosmological constant problem is proposed by modifying Einstein's theory of general relativity, using instead a scalar-tensor theory of gravitation. This theory of gravity crucially incorporates the concept of quantum…

General Relativity and Quantum Cosmology · Physics 2011-10-28 Thomas L. Wilson

A time-varying cosmological "constant" Lambda is consistent with Einstein's equation, provided matter and/or radiation is created or destroyed to compensate for it. Supposing an empty primordial universe endowed with a very large…

General Relativity and Quantum Cosmology · Physics 2014-11-17 R. Aldrovandi , J. P. Beltran Almeida , J. G. Pereira