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In this work, we study the cosmological constant problem and Hubble tension in the void-dominated cosmology scenario \cite{Yusofi:2022hgg}. For this goal, we will first consider the cosmic voids in the cosmic web as interconnected ideal…

Cosmology and Nongalactic Astrophysics · Physics 2022-08-26 E. Yusofi , M. A. Ramzanpour

Based on quantum mechanical framework for the minimal length uncertainty, we demonstrate that the generalized uncertainty principle (GUP) parameter could be best constrained by recent gravitational waves observations on one hand. On other…

General Relativity and Quantum Cosmology · Physics 2021-02-26 Abdel Magied Diab , Abdel Nasser Tawfik

The existence of a small, non-zero cosmological constant is one of the major puzzles in fundamental physics. Naively, quantum field theory arguments would imply a cosmological constant which is up to 10$^{120}$ times larger than the…

General Physics · Physics 2022-09-08 Michael Bishop , Joey Contreras , Peter Martin , Douglas Singleton

We generalize the fractal bubble model (FB), recently proposed in the literature as an alternative to the standard $\Lambda$CDM cosmology, to include a non-zero cosmological constant. We retain the same volume partition of voids and walls…

General Relativity and Quantum Cosmology · Physics 2012-01-30 Stefano Viaggiu

We suggest that the solution to the cosmological vacuum energy puzzle does not require any new field beyond the standard model, but rather can be explained as a result of the interaction of the infrared sector of the effective theory of…

Cosmology and Nongalactic Astrophysics · Physics 2011-07-13 Federico R. Urban , Ariel R. Zhitnitsky

We propose a new approach to understand hierarchy problem for cosmological constant in terms of considering noncommutative nature of space-time. We calculate that vacuum energy density of the noncommutative quantum field theories in…

High Energy Physics - Theory · Physics 2007-05-23 Xiao-Jun Wang

We investigate the imprints of the Generalized Uncertainty Principle on cosmological scales by using redshift-space distortion measurements in combination with background cosmological data to determine constraints on the deformation…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-03 Andronikos Paliathanasis

The author proposed in his previous papers in 2001 that the problem of the cosmological constant could be resolved and its calculated value agrees excellently with the observations by assuming that the space-time itself, as the phase of…

General Physics · Physics 2007-05-23 H. M. Mok

Standard cosmology has long been plagued by a number of persistent problems. The origin of the apparent acceleration of the cosmic expansion remains enigmatic. The cosmological constant has been reintroduced as a free parameter with a value…

General Physics · Physics 2023-02-28 Jan O. Stenflo

A diverse set of observations now compellingly suggest that Universe possesses a nonzero cosmological constant. In the context of quantum-field theory a cosmological constant corresponds to the energy density of the vacuum, and the wanted…

Astrophysics · Physics 2014-10-13 Lawrence M. Krauss , Michael S. Turner

The cosmological constant problem is explained by a theory based on the discrete space-time hypothesis. The calculated cosmological constant value is of the order of 10^-52[m]^-2 or equivalent to about 0.7 of the critical mass density. It…

Astrophysics · Physics 2007-05-23 H. M. Mok

We propose that the observed value of the cosmological constant may be explained by a fundamental uncertainty in the spacetime metric, which arises when combining the principle that mass and energy curve spacetime with the quantum…

General Relativity and Quantum Cosmology · Physics 2025-05-20 Ahmed Farag Ali , Nader Inan

The value of the cosmological constant arising from a crystalline model for vacuum cosmic space with lattice parameter of the order of the neutron radius [1] has been calculated. The model allows to solve, in an easy way, the problem of the…

The observed cosmological constant may originate as the minimum value $U_{min}$ of a scalar field potential, where the scalar field is frozen due to a large mass. If this vacuum is metastable, it may decay to a true vacuum either at present…

General Relativity and Quantum Cosmology · Physics 2025-03-27 Dimitrios Efstratiou , Leandros Perivolaropoulos

Fundamental constants are a cornerstone of our physical laws. Any constant varying in space and/or time would reflect the existence of an almost massless field that couples to matter. This will induce a violation of the universality of free…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Jean-Philippe Uzan

In this thesis the cosmological constant is investigated from two points of view. First, we study the influence of a time-dependent cosmological constant on the late-time expansion of the universe. Thereby, we consider several combinations…

High Energy Physics - Theory · Physics 2007-05-23 Florian Bauer

We consider a dynamical approach to the cosmological constant. There is a scalar field with a potential whose minimum occurs at a generic, but negative, value for the vacuum energy, and it has a non-standard kinetic term whose coefficient…

High Energy Physics - Theory · Physics 2016-09-06 Shinji Mukohyama , Lisa Randall

We explore the effects of a positive cosmological constant on astrophysical and cosmological configurations described by a polytropic equation of state. We derive the conditions for equilibrium and stability of such configurations and…

Astrophysics · Physics 2008-11-26 Andres Balaguera-Antolinez , David F. Mota , Marek Nowakowski

With the motivation in mind to evaluate the contribution of the cosmological constant $\Lambda$ on the foam like patterns formation process in the distribution of galaxies, we investigate the Newtonian dynamics of a spherical void embedded…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Roland Triay , Henri-Hugues Fliche

This article aims at discussing the cosmological constant problem at a pedagogical but fully technical level. We review how the vacuum energy can be regularized in flat and curved space-time and how it can be understood in terms of Feynman…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Jerome Martin
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