English
Related papers

Related papers: Artificial contradiction between cosmology and par…

200 papers

A new perspective on the Cosmological Constant Problem (CCP) is proposed and discussed within the multiverse approach of Quantum Cosmology. It is assumed that each member of the ensemble of universes has a characteristic scale $a$ that can…

General Relativity and Quantum Cosmology · Physics 2020-09-09 Vesselin G. Gueorguiev , Andre Maeder

In this paper we provide both a diagnosis and resolution of the cosmological constant problem, one in which a large (as opposed to a small) cosmological constant $\Lambda$ can be made compatible with observation. We trace the origin of the…

Astrophysics · Physics 2009-10-31 Philip D. Mannheim

We trace the origin of the cosmological constant problem to the assumption that Newton's constant $G$ sets the scale for cosmology. And then we show that once this assumption is relaxed, the very same cosmic acceleration which has served to…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Philip D. Mannheim

Recently, there have been claims in the literature that the cosmological constant problem can be dynamically solved by specific compactifications of gravity from higher-dimensional toy models. These models have the novel feature that in the…

High Energy Physics - Theory · Physics 2016-07-04 Mark P. Hertzberg , Ali Masoumi

We present a necessary and sufficient condition for an object of any mass m to be a quantum black hole (q.b.h.): The product of the cosmological constant lambda and the Planck constant h, lambda and h corresponding to the scale defined by…

General Physics · Physics 2010-02-04 Antonio Alfonso-Faus

In a recent paper (Vigoureux et al. Int. J. Theor. Phys. 47:928, 2007) it has been suggested that the velocity of light and the expansion of the universe are two aspects of one single concept connecting space and time in the expanding…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-22 David Viennot , Jean-Marie Vigoureux

The Planck scale is usually believed to be an unpassable wall. Putting a cutoff there and thinking of it as a quantized spacetime entity shows that. However, this is exactly the cause of many problems in quantum gravity. The cosmological…

High Energy Physics - Theory · Physics 2023-07-13 Ken-ji Hamada

Planck units are natural physical scales of mass, length and time, built with the help of the fundamental constants $\hbar, c, G$. The functional role of the constants used for the construction of Planck units is different. If the first two…

General Physics · Physics 2017-01-05 Yu. L. Bolotin , V. V. Yanovsky

We present a new solution to the cosmological constant (CC) and coincidence problems in which the observed value of the CC, $\Lambda$, is linked to other observable properties of the universe. This is achieved by promoting the CC from a…

General Relativity and Quantum Cosmology · Physics 2015-03-17 Douglas J. Shaw , John D. Barrow

We use the quantum unimodular theory of gravity to relate the value of the cosmological constant, $\Lambda$, and the energy scale for the emergence of cosmological classicality. The fact that $\Lambda$ and unimodular time are complementary…

High Energy Physics - Theory · Physics 2023-01-04 Niayesh Afshordi , João Magueijo

We show that the cosmological constant appears as a Lagrange multiplier if nature is described by a canonical noncommutative spacetime. It is thus an arbitrary parameter unrelated to the action and thus to vacuum fluctuations. The…

High Energy Physics - Theory · Physics 2008-11-26 Xavier Calmet

The paper deals with the scale discrepancy between the observed vacuum energy in cosmology and the theoretical quantum vacuum energy (cosmological constant problem). Here, we demonstrate that Einstein's equation and an analogy to particle…

General Physics · Physics 2019-02-08 Christian Henke

We consider further consequences of recently [1] revealed role of cosmological constant \Lambda as of a physical constant, along with the gravitational one to define the gravity i.e. the General Relativity and its low-energy limit. We now…

General Physics · Physics 2019-03-13 V. G. Gurzadyan , A. Stepanian

I briefly review the cosmological constant problem and the issue of dark energy (or quintessence). Within the framework of quantum field theory, the vacuum expectation value of the energy momentum tensor formally diverges as $k^4$. A cutoff…

Astrophysics · Physics 2008-11-26 Varun Sahni

In this paper we suggest that the Planck length $l_{pl}$ and the Cosmological Constant scale $r_\Lambda=\frac{1}{\sqrt{\Lambda}}$ could in principle be dual each other if we take seriously the so-called q-Bargmann Fock space representation…

General Relativity and Quantum Cosmology · Physics 2012-09-11 Ivan Arraut

The cosmological constant (CC) term in Einstein's equations, Lambda, was first associated to the idea of vacuum energy density. Notwithstanding, it is well-known that there is a huge, in fact appalling, discrepancy between the theoretical…

General Relativity and Quantum Cosmology · Physics 2015-03-19 Joan Sola

According to general relativity, the present analysis shows on geometrical grounds that the cosmological constant problem is an artifact due to the unfounded link of this fundamental constant to vacuum energy density of quantum…

General Relativity and Quantum Cosmology · Physics 2011-07-19 Roland Triay

We critically review several recent approaches to solving the two cosmological constant problems. The "old" problem is the discrepancy between the observed value of $\Lambda$ and the large values suggested by particle physics models. The…

High Energy Physics - Theory · Physics 2009-10-31 J. Garriga , A. Vilenkin

We find five fundamental reasons demanding that any gravitational mass m, and the speed of light c, vary with cosmological time such that mc remains constant. This is required by the universal condition of conservation of momentum in a…

General Physics · Physics 2015-06-26 Antonio Alfonso-Faus

Why the cosmological constant $\Lambda$ observed today is so much smaller than the Planck scale or why the universe is accelerating at present? This is so-called the cosmological constant fine-tuning problem. In this paper, we find that…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-26 Chao-Jun Feng , Xin-Zhou Li
‹ Prev 1 2 3 10 Next ›