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The belief still persists, at least for an important part of the community, that in general relativity the cosmological constant $\Lambda$ must remain immaculate. However, Bianchi identities show that $\Lambda$ could acquire local…

General Relativity and Quantum Cosmology · Physics 2022-02-25 J. Ovalle

In this letter we investigate some consequences of considering our 4D observable universe as locally and isometrically embeded into a 5D spacetime, where gravity is described by a Brans-Dicke theory in vacuum. Once we impose the embeding…

General Relativity and Quantum Cosmology · Physics 2017-06-28 José Edgar Madriz Aguilar , J. Zamarripa , A. Peraza , J. A. Licea

We consider extra compact dimensions as the origin of a cosmological universal energy density in the regular dimensions, with only graviton fields propagating in the compact space dimensions. The quantum zero point energy originating from…

General Relativity and Quantum Cosmology · Physics 2015-09-03 Vikram Soni , Naresh Dadhich , Rathin Adhikari

Next year we will celebrate 100 years of the cosmological term, $\Lambda$, in Einstein's gravitational field equations, also 50 years since the cosmological constant problem was first formulated by Zeldovich, and almost about two decades of…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-14 Joan Sola

We review current observations of the homogeneous cosmological expansion which, because they measure only kinematic variables, cannot determine the dynamics driving the recent accelerated expansion. The minimal fit to the data, the flat…

Astrophysics · Physics 2015-05-13 Sidney Bludman

We first review the cosmological constant problem, and then mention a conjecture of Feynman according to which the general relativistic theory of gravity should be reformulated in such a way that energy does not couple to gravity. We point…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Murat Özer

The notion of ``fundamental constant'' is heavily theory-laden. A natural, fairly precise formulation is possible in the context of the standard model (here defined to include gravity). Some fundamental constants have profound geometric…

High Energy Physics - Phenomenology · Physics 2007-09-03 Frank Wilczek

New general spherically symmetric solutions have been derived with a cosmological "constant" \Lambda as a source. This \Lambda field is not constant but it satisfies the properties of the asymptotically safe gravity at the ultraviolet fixed…

High Energy Physics - Theory · Physics 2023-09-26 Georgios Kofinas , Vasilios Zarikas

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

We showed that the principle of nongravitating vacuum energy, when formulated in the first order formalism, solves the cosmological constant problem. The most appealing formulation of the theory displays a local symmetry associated with the…

General Relativity and Quantum Cosmology · Physics 2011-09-09 E. I. Guendelman , A. B. Kaganovich

A holistic view of the cosmological appearance and development of space is obtained by studying space as a spherically closed surface of a 4-sphere in a zero energy balance between motion and gravitation. Such an approach re-establishes…

Astrophysics · Physics 2009-11-13 Tuomo Suntola

We propose that gravity be intrinsically quantum-mechanical, so that in the absence of quantum mechanics the geometry of the universe would be Minkowski. We show that in such a situation gravity does not require any independent quantization…

High Energy Physics - Theory · Physics 2015-05-19 Philip D. Mannheim

In this paper we bring to light an hitherto undisclosed richness of this Theory, namely its admitting a consistent reformulation which is able to provide a unified scenario for all kinds of particles, be they lightlike or not. This result…

General Relativity and Quantum Cosmology · Physics 2008-04-14 Fernando de Felice , Giovanni Preti

In this letter we will revise the steps followed by A. Einstein when he first wrote on cosmology from the point of view of the general theory of relativity. We will argue that his insightful line of thought leading to the introduction of…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Carlos Barcelo

The Einstein's equivalence principle is formulated in terms of the accuracy of measurements and its dependence of the size of the area of measurement. It is shown that different refinements of the statement 'the spacetime is locally flat'…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Vladik Kreinovich , R. R. Zapatrin

In this paper we present a framework in which the relational description of General Relativity can be used to smoothly continue cosmological dynamical systems through the Big Bang without invoking quantum gravity effects. Cosmological…

General Relativity and Quantum Cosmology · Physics 2024-06-03 Josh Hoffmann , David Sloan

The Einstein theories of space-time and gravity as well the stander cosmology are reconstructed thoroughly in this paper based on flat reference frame. The rational parts of the Einstein theories are reserved while the irrational parts…

General Physics · Physics 2007-05-23 Mei Xiaochun

We consider general relativity with cosmological constant minimally coupled to electromagnetic field and assume that four-dimensional space-time manifold is the warped product of two surfaces with Lorentzian and Euclidean signature metrics.…

General Physics · Physics 2019-07-31 D. E. Afanasev , M. O. Katanaev

We have studied the evolution of the Universe in the generalized Einstein action of the form $R+\beta R^2$, where $R$ is the scalar curvature and $\beta=\rm const.$. We have found exact cosmological solutions that predict the present cosmic…

High Energy Physics - Theory · Physics 2008-11-21 Arbab I. Arbab

According to the holographic principle, the maximum amount of information stored in a region of space scales as the area of its two-dimensional surface, like a hologram. We show that the holographic principle can be understood heuristically…

General Relativity and Quantum Cosmology · Physics 2016-10-21 Y. Jack Ng
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