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Related papers: On Topological Defects and Cosmological Constant

200 papers

The interesting early history of the cosmological term is reviewed, beginning with its introduction by Einstein in 1917 and ending with two papers of Zel'dovich, shortly before the advent of spontaneously broken gauge theories. Beside…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Norbert Straumann

In this paper we consider the implications of a cosmological constant for the evolution of the universe, under a set of assumptions motivated by the holographic and horizon complementarity principles. We discuss the ``causal patch"…

High Energy Physics - Theory · Physics 2009-11-07 Lisa Dyson , Matthew Kleban , Leonard Susskind

We make the cosmological constant, {\Lambda}, into a field and restrict the variations of the action with respect to it by causality. This creates an additional Einstein constraint equation. It restricts the solutions of the standard…

General Relativity and Quantum Cosmology · Physics 2015-05-28 John D. Barrow , Douglas J. Shaw

In this paper, time variable cosmological constant, dubbed {\it age cosmological constant}, is investigated motivated by the fact: any cosmological length scale and time scale can introduce a cosmological constant or vacuum energy density…

Cosmology and Nongalactic Astrophysics · Physics 2010-06-28 Lixin Xu , Jianbo Lu , Wenbo Li

A cosmological constant, Lambda, is the most natural candidate to explain the origin of the dark energy (DE) component in the Universe. However, due to experimental evidence that the equation of state (EOS) of the DE could be evolving with…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Joan Sola , Hrvoje Stefancic

The accelerating expansion of the Universe points to a small positive value for the cosmological constant or vacuum energy density. We discuss recent ideas that the cosmological constant plus LHC results might hint at critical phenomena…

High Energy Physics - Phenomenology · Physics 2015-07-09 Steven D. Bass

The work shows that the associated Einstein like gravity for the Klein-Gordon field shows the spontaneous emergence of the cosmological pressure tensor density (CPTD) that in the classical limit leads to the cosmological constant (CC). Even…

General Physics · Physics 2020-07-07 Piero Chiarelli

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

The Einstein static universe has played a central role in a number of emergent scenarios recently put forward to deal with the singular origin of the standard cosmological model. Here we study the existence and stability of the Einstein…

Cosmology and Nongalactic Astrophysics · Physics 2009-09-01 Saulo Carneiro , Reza Tavakol

The cosmological constant problem is studied in a two component cosmological model. The universe contains a cosmological constant of an arbitrary size and sign and an additional component with an inhomogeneous equation of state. It is shown…

General Relativity and Quantum Cosmology · Physics 2009-01-16 Hrvoje Stefancic

In creating his gravitational field equations Einstein unjustifiedly assumed that inertial mass, and its energy equivalent, is a source of gravity. Denying this assumption allows modifying the field equations to a form in which a positive…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Homer G. Ellis

We show that the description of the space-time of general relativity as a diagonal four dimensional submanifold immersed in an eight dimensional hypercomplex manifold, in torsionless case, leads to a geometrical origin of the cosmological…

General Relativity and Quantum Cosmology · Physics 2016-10-31 Hemza Azri , A. Bounames

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

After a short history of the $\Lambda$-term it is explained why the (effective) cosmological constant is expected to obtain contributions from short-distance-physics, corresponding to an energy scale of at least 100 GeV. The actual tiny…

Astrophysics · Physics 2009-10-31 N. Straumann

The fluctuations of the vacuum energy are treated as a non-equilibrium process and a stochastic model for the cosmological constant is presented, which yields a natural explanation for the smallness or zero value of the constant in the…

Astrophysics · Physics 2007-05-23 J. W. Moffat

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

The accelerated expansion of the universe has been established through observations of supernovae, the growth of structure, and the cosmic microwave background. The most popular explanation is Einsteins cosmological constant, or dynamic…

General Physics · Physics 2021-09-08 Steen H. Hansen

For almost a century, the cosmological constant has been a mysterious object, in relation to both its origin and its very small value. By using a Bose-Einstein condensate analogue model for gravitational dynamics, we address here the…

General Relativity and Quantum Cosmology · Physics 2012-07-25 Stefano Finazzi , Stefano Liberati , Lorenzo Sindoni

One hope to solve the cosmological constant problem is to identify a symmetry principle, based on which the cosmological constant can be reduced either to zero, or to a tiny value. Here, we note that requiring that the vacuum state is…

General Relativity and Quantum Cosmology · Physics 2011-06-01 Jurjen F. Koksma , Tomislav Prokopec

Two sides of cosmological constant problem are discussed: a mysterious compensation of all contributions to vacuum energy with the accuracy of 100-50 orders of magnitude and a surprising equality of a constant vacuum energy density to the…

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