English
Related papers

Related papers: On cosmological constant in Causal Set theory

200 papers

Combining general relativity and gravitational gauge theory, the cosmological constant is determined theoretically. The cosmological constant is related to the average vacuum energy of gravitational gauge field. Because the vacuum energy of…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Ning Wu , Germano Resconi , Zhan Xu , Zhi-Peng Zheng , Da-Hua Zhang , Tu-Nan Ruan

The cosmological constant problem and brane universes are reviewed briefly. We discuss how the cosmological constant problem manifests itself in various scenarios for brane universes. We review attempts - and their difficulties - that aim…

High Energy Physics - Theory · Physics 2009-11-11 Ulrich Ellwanger

The idea of possible time or space variations of the `fundamental' constants of nature, although not new, is only now beginning to be actively considered by large numbers of researchers in the particle physics, cosmology and astrophysics…

Astrophysics · Physics 2009-11-07 C. J. A. P. Martins

The possibility of extending the quantum mechanical superposition principle to free parameters such as the cosmological constant appearing in the Lagrangian of physical theories is examined. If the cosmological constant is subject to a…

General Relativity and Quantum Cosmology · Physics 2017-12-15 Josily Cyriac

We discuss the cosmological constant problem in the context of higher codimension brane world scenarios with infinite-volume extra dimensions. In particular, by adding higher curvature terms in the bulk action we are able to find smooth…

High Energy Physics - Theory · Physics 2009-11-07 Olindo Corradini , Alberto Iglesias , Zurab Kakushadze

A covariant Lagrangian formulation of a solution to the cosmological constant problem, based on vizualising the fluctuations of the vacuum energy as a non-equilibrium process with stochastic behaviour, is presented. The variational…

Astrophysics · Physics 2016-08-30 J. W. Moffat

We address issues on the origin of gravity and the cosmological constant problem based on a recent understanding about the correspondence between noncommutative field theory and gravity. We suggest that the cosmological constant problem can…

High Energy Physics - Theory · Physics 2008-03-28 Hyun Seok Yang

We compute the cosmological constant in a scale invariant scalar field theory. The gravitational action is also suitably modified to respect scale invariance. Due to scale invariance the theory does not admit a cosmological constant term.…

High Energy Physics - Phenomenology · Physics 2010-11-15 Pankaj Jain , Subhadip Mitra

The flatness and cosmological constant problems are solved with varying speed of light c, gravitational coupling strength G and cosmological parameter Lambda, by explicitly assuming energy conservation of observed matter. The present…

General Relativity and Quantum Cosmology · Physics 2009-10-31 P. Gopakumar , G. V. Vijayagovindan

We first give simple arguments in favor of the "Zero Constants Party", i.e. that quantum theory should not contain fundamental dimensionful constants at all. Then we argue that quantum theory should proceed not from a space-time background…

General Physics · Physics 2010-05-04 Felix M. Lev

We introduce a dynamical model to reduce a large cosmological constant to a sufficiently small value. The basic ingredient in this model is a distinction which has been made between the two unit systems used in cosmology and particle…

General Relativity and Quantum Cosmology · Physics 2010-05-12 Yousef Bisabr

Although the cosmological constant has primarily cosmological consequences, its smallness poses one of the basic problems in particle physics. Various attempts have been made to explain this mystery, but no satisfactory solution has been…

High Energy Physics - Phenomenology · Physics 2007-05-23 Hans Peter Nilles

In this paper, we study in detail a perfect fluid cosmological model with time-varying "constants" using dimensional analysis and the symmetry method. We examine the case of variable "constants" in detail without considering the perfect…

General Relativity and Quantum Cosmology · Physics 2009-12-30 José Antonio Belinchón , Indrajit Chakrabarty

We point out several subtleties arising in brane-world scenarios of cosmological constant cancellation. We show that solutions with curvature singularities are inconsistent, unless the contribution to the effective four-dimentional…

High Energy Physics - Theory · Physics 2009-10-31 Stefan Forste , Zygmunt Lalak , Stéphane Lavignac , Hans Peter Nilles

The purpose of this study is to describe a perfect fluid matter distribution that leads to a constant curvature region, thanks to the effect of a non-minimal coupling. This distribution exhibits a density profile within the range found in…

General Relativity and Quantum Cosmology · Physics 2011-07-04 J. Páramos , O. Bertolami

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

We study the role of the cosmological constant (CC) as a component of dark energy (DE). It is argued that the cosmological term is in general unavoidable and it should not be ignored even when dynamical DE sources are considered. From the…

High Energy Physics - Theory · Physics 2011-01-13 Florian Bauer

We consider a model for gravity that is invariant under global scale transformations. It includes one extra real scalar field coupled non-minimally to the gravity fields. In this model all the dimensionful parameters like the gravitational…

General Relativity and Quantum Cosmology · Physics 2012-02-06 Pankaj Jain , Purnendu Karmakar , Subhadip Mitra , Sukanta Panda , Naveen K. Singh

This is a review of the physics and cosmology of the cosmological constant. Focusing on recent developments, I present a pedagogical overview of cosmology in the presence of a cosmological constant, observational constraints on its…

Astrophysics · Physics 2015-06-24 Sean M. Carroll

The mystery of the cosmological constant is probably the most pressing obstacle to significantly improving the models of elementary particle physics derived from string theory. The problem arises because in the standard framework of low…

High Energy Physics - Phenomenology · Physics 2007-05-23 Edward Witten
‹ Prev 1 3 4 5 6 7 10 Next ›