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Related papers: Relaxing a large cosmological constant

200 papers

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 cosmological constant is one of the most pressing problems in modern physics. We address this issue from an emergent gravity standpoint, by using an analogue gravity model. Indeed, the dynamics of the emergent metric in a Bose-Einstein…

General Relativity and Quantum Cosmology · Physics 2012-02-29 Stefano Finazzi , Stefano Liberati , Lorenzo Sindoni

The cosmological constant problem arises at the intersection between general relativity and quantum field theory, and is regarded as a fundamental problem in modern physics. In this paper we describe the historical and conceptual origin of…

High Energy Physics - Theory · Physics 2007-05-23 Svend Erik Rugh , Henrik Zinkernagel

A new vision of the beginning and expansion of our universe has produced a solution to the vacuum energy problem (also known as "cosmological constant problem"). A new dynamic of cellular spaces and a discrete time has space being produced…

Astrophysics · Physics 2007-05-23 Charles B. Leffert

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

For two decades the hot big-bang model as been referred to as the standard cosmology -- and for good reason. For just as long cosmologists have known that there are fundamental questions that are not answered by the standard cosmology and…

Astrophysics · Physics 2007-05-23 Michael S. Turner

We present a possible understanding to the issues of cosmological constant, inflation, matter and coincidence problems based only on the Einstein equation and Hawking particle production. The inflation appears and results agree to…

General Physics · Physics 2020-06-26 She-Sheng Xue

One often hears that the strong $CP$ problem is the one problem which cannot be solved by anthropic reasoning. We argue that this is not so. Due to nonperturbative dynamics, states with a different $CP$ violating paramenter $\theta$ acquire…

High Energy Physics - Theory · Physics 2017-12-11 Nemanja Kaloper , John Terning

The fact that the energy densities of dark energy and matter are similar currently, known as the coincidence problem, is one of the main unsolved problems of cosmology. We present here a model in which a spatial curvature of the universe…

Astrophysics · Physics 2009-11-13 Urbano Franca

A scalar-tensor theory of gravity is formulated in which $G$ and particle masses are allowed to vary. The theory yields a globally static cosmological model with no evolutionary timescales, no cosmological coincidences, and no flatness and…

General Physics · Physics 2015-10-01 Meir Shimon

The dynamics of density and metric perturbations is investigated for the previously developed model where the decay of the vacuum energy into matter (or vice versa) is due to the renormalization group (RG) running of the cosmological…

General Relativity and Quantum Cosmology · Physics 2010-10-27 Julio C. Fabris , Ilya L. Shapiro , Joan Sola

In this paper, it is shown that the cosmological model that was introduced in a sequence of three earlier papers under the title, A Dust Universe Solution to the Dark Energy Problem can be used to analyse and solve the Cosmological…

General Physics · Physics 2008-07-13 James G. Gilson

The Cosmological Constant Problem emerges when Quantum Field Theory is applied to the gravitational theory, due to the enormous magnitude of the induced energy of the vacuum. The unique known solution of this problem involves an extremely…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Ilya L. Shapiro , Joan Sola

Starting from generic quantum effects at the Planck scale M_P, we find that the renormalization group running of the cosmological constant (CC) at low energies is possible if there is a smooth decoupling of all massive particles from M_P to…

High Energy Physics - Phenomenology · Physics 2009-11-10 Ilya L. Shapiro , Joan Sola

In this review, I discuss briefly how the presence of a cosmological constant in the Universe may imply a decoherent evolution of quantum matter in it, and as a consequence a fundamental irreversibility of time unrelated in principle to CP…

General Relativity and Quantum Cosmology · Physics 2007-05-23 N. E. Mavromatos

We propose a time-varying cosmological constant with a fixed equation of state, which evolves mainly through its interaction with the background during most of the long history of the universe. However, such interaction does not exist in…

Cosmology and Nongalactic Astrophysics · Physics 2009-08-18 Murli Manohar Verma

The $\Lambda$ Cold Dark Matter model ($\Lambda$CDM) represents the current standard model in cosmology. Within this, there is a tension between the value of the Hubble constant, $H_0$, inferred from local distance indicators and the angular…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-26 Edvard Mörtsell , Suhail Dhawan

We construct the cosmological model to explain the cosmological constant problem. We built the extension of the standard cosmological model $\Lambda$CDM by consideration of decaying vacuum energy represented by the running cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2015-07-08 Marek Szydlowski

The cosmological constant problem is a fundamental issue that has puzzled researchers in the fields of theoretical physics and cosmology for a long time. It arises from the discrepancy between the observed value of the cosmological constant…

General Relativity and Quantum Cosmology · Physics 2024-01-10 Alexander I Nesterov

The mechanism for the relaxation of the cosmological constant is studied and elaborated. In the model used for the analysis of the relaxation mechanism the universe contains two components: a cosmological constant of an arbitrary size and…

General Relativity and Quantum Cosmology · Physics 2008-12-22 Hrvoje Stefancic