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Related papers: The cosmological constant problem: a user's guide

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It is shown that the usual choice of units obtained by taking G = c = Planck constant = 1, giving the Planck units of mass, length and time, introduces an artificial contradiction between cosmology and particle physics: the lambda problem…

General Physics · Physics 2009-04-17 Antonio Alfonso-Faus

The current vacuum energy density observed as dark energy ${ \rho }_{ \rm dark }\simeq 2.5\times10^{-47}\ {\rm GeV^{4}}$ is unacceptably small compared with any other scales. Therefore, we encounter serious fine-tuning problem and…

High Energy Physics - Theory · Physics 2017-06-07 Kazunori Kohri , Hiroki Matsui

The Standard Model of particle physics and the theory of General Relativity (GR) currently provide a good description of almost all phenomena of particle physics and gravitation that have received controlled experimental tests. However, the…

Atomic Physics · Physics 2009-01-23 Thomas Dent

The cosmological constant (vacuum energy) problem is analyzed within the scope of quantum theories with UV-cut-off or fundamental length. Various cases associated with the appearance of the latter are considered both using the Generalized…

General Relativity and Quantum Cosmology · Physics 2007-12-20 A. E. Shalyt-Margolin

We consider an effective field theory description of gravity coupled to a scalar field with volume-preserving diffeomorphism and Weyl invariances. The smallness of the cosmological constant is achieved when the potential of the scalar is…

High Energy Physics - Phenomenology · Physics 2007-05-23 K. -I. Izawa

A calculation by E.D. Jones of the cosmological mass scale for the phase transition from pre-geometric to physical description as about 5 Tev could be interpreted as a prediction of an effective threshold for novel physical effects in…

High Energy Physics - Theory · Physics 2007-05-23 H. Pierre Noyes

Working in the context of the Planck scale cosmology formulation of Bonanno and Reuter, we use our resummed quantum gravity approach to Einstein's general theory of relativity to estimate the value of the cosmological constant as…

High Energy Physics - Theory · Physics 2018-11-05 B. F. L. Ward

The fundamental laws of physics are required to be invariant under local spatial scale change. In 3-dimensional space, this leads to a variation in Planck constant \hbar and speed of light c. They vary as \hbar ~ a^(1/2) and c ~ a^(-1/2), a…

General Physics · Physics 2013-02-28 Hoang K. Nguyen

Three of the big puzzles of theoretical physics are the following: (i) There is apparently no time evolution in the dynamics of quantum general relativity, because the allowed quantum states must obey the Hamiltonian constraint. (ii) During…

General Relativity and Quantum Cosmology · Physics 2015-12-29 Shreya Banerjee , Sayantani Bera , Tejinder P. Singh

We argue that scale invariance is not anomalous in quantum field theory, provided it is broken cosmologically. We consider a locally scale invariant extension of the Standard Model of particle physics and argue that it fits both the…

High Energy Physics - Phenomenology · Physics 2010-08-19 Pankaj Jain , Subhadip Mitra

We propose a technically natural scenario whereby an initially large cosmological constant (c.c.) is relaxed down to the observed value due to the dynamics of a scalar evolving on a very shallow potential. The model crucially relies on a…

High Energy Physics - Theory · Physics 2017-01-04 Lasma Alberte , Paolo Creminelli , Andrei Khmelnitsky , David Pirtskhalava , Enrico Trincherini

In this paper, we give a possible solution to the cosmological constant problem. It is shown hat the traditional approach, based on volume weighting of probabilities, leads to an incoherent onclusion: the probability that a randomly chosen…

General Relativity and Quantum Cosmology · Physics 2015-06-04 Artyom V. Astashenok , Antonino Del Popolo

The energy density of the vacuum, Lambda, is at least 60 orders of magnitude smaller than several known contributions to it. Approaches to this problem are tightly constrained by data ranging from elementary observations to precision…

High Energy Physics - Theory · Physics 2008-11-26 Raphael Bousso

A nonlocal quantum gravity theory is presented which is finite and unitary to all orders of perturbation theory. Vertex form factors in Feynman diagrams involving gravitons suppress graviton and matter vacuum fluctuation loops by…

High Energy Physics - Theory · Physics 2011-08-17 J. W. Moffat

Several attempts to solve the cosmological constant problem, which concerns the value of the cosmological constant being extremely smaller than the Standard Model mass scales, have introduced a scalar field with a very flat potential that…

High Energy Physics - Phenomenology · Physics 2024-04-10 Wen Yin

The comparison of the Standard Cosmological Model (SCM) with astronomical observations, i.e. theory versus experiment, and with the Minimal Standard Model (MSM) in particle physics, i.e. theory versus theory, is discussed. The main issue of…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. D. Dolgov

The standard formulation of the cosmological constant problem is based on one critical assumption---the spacetime is homogeneous and isotropic, which is true only on cosmological scales. However, this problem is caused by extremely small…

General Relativity and Quantum Cosmology · Physics 2020-08-05 Qingdi Wang

We have studied a cosmological model with a cosmological term of the form $\Lambda=3\alpha\fr{\dot R^2}{R^2}+\bt\fr{\ddot R}{R}+\fr{3\gamma}{R^2} \alpha, \ \bt \gamma$ are constants. The scale factor (R) is found to vary linearly with time…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Arbab I. Arbab

The cosmological tests are tight enough now to show that the Friedmann-Lemaitre Lambda CDM cosmological model almost certainly is a useful approximation. This means general relativity theory passes significant tests of the extrapolation of…

Astrophysics · Physics 2017-08-23 P. J. E. Peebles

Based on an analysis of the entropy associated to the vacuum quantum fluctuations, we show that the holographic principle, applied to the cosmic scale, constitutes a possible explanation for the observed value of the cosmological constant,…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Saulo Carneiro
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