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相关论文: The Closed Cosmological Model with Variable Lambda…

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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…

高能物理 - 理论 · 物理学 2008-11-26 Raphael Bousso

A phenomenological model is proposed to explain the recent observed cosmological variation of the fine structure constant as an effect of the quantum vacuum, assuming a flat universe with cosmological constant $\Lambda$ in the cases…

天体物理学 · 物理学 2010-12-17 Antonio F. Rañada

The problem of the physical nature and the cosmological genesis of Lambda-term is discussed. This problem can't be solved in terms of the current quantum field theory which operates with Higgs and non-perturbative vacuum condensates and…

广义相对论与量子宇宙学 · 物理学 2007-05-23 V. Burdyuzha , O. Lalakulich , G. Vereshkov , Yu. Ponomarev

A time-varying cosmological "constant" Lambda is consistent with Einstein's equation, provided matter and/or radiation is created or destroyed to compensate for it. Supposing an empty primordial universe endowed with a very large…

广义相对论与量子宇宙学 · 物理学 2014-11-17 R. Aldrovandi , J. P. Beltran Almeida , J. G. Pereira

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…

宇宙学与河外天体物理 · 物理学 2009-08-18 Murli Manohar Verma

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…

综合物理 · 物理学 2019-03-13 V. G. Gurzadyan , A. Stepanian

The cosmological constant $\Lambda$ is a measure of the energy density of the vacuum. Therefore properties of the energy of the system in the metastable vacuum state reflect properties of $\Lambda = \Lambda(t)$. We analyze properties of the…

广义相对论与量子宇宙学 · 物理学 2022-03-23 Krzysztof Urbanowski

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 at least as large as the Fermi scale. The…

天体物理学 · 物理学 2007-05-23 Norbert Straumann

It is pointed out that a collider experiment involves a local contribution to the energy-momentum tensor, a circumstance which not a common feature of the current state of the Universe at large characterized by the cosmological constant…

高能物理 - 理论 · 物理学 2015-06-26 Freydoon Mansouri

The cosmological constant term (CC), $\Lambda$, is a pivotal ingredient in the standard model of cosmology or $\Lambda$CDM, but it is a rigid quantity for the entire cosmic history. This is unnatural and inconsistent. Different theoretical…

高能物理 - 理论 · 物理学 2024-11-12 Joan Solà Peracaula , Cristian Moreno-Pulido

A mechanism for suppressing the cosmological constant is developed, based on an analogy with a superconducting phaseshift in which free fermions coupled perturbatively to a weak gravitational field are in an unstable false vacuum state. The…

高能物理 - 理论 · 物理学 2007-05-23 Stephon Alexander , Manasse Mbonye , John Moffat

The present work deals with the cosmological consequences of the variable cosmological term $\Lambda(a)=\Lambda_0 + \Lambda_1 a^{-r} + \Lambda_2 a^{-s},$ where $a$ is the scale factor of the Robertson-Walker space-time. An analysis of the…

综合物理 · 物理学 2020-01-22 Christian Henke

With the basic cosmological relations that agree with the recent observations, simple expressions are suggested concerning the value of cosmological constant($\Lambda$). A large contribution of quantum vacuum to the energy momentum tensor…

广义相对论与量子宇宙学 · 物理学 2007-05-23 Ishwaree P. Neupane

We propose a new cosmological model with a time-dependent cosmological constant ($\Lambda\propto 1/t^2$), which starting at the Planck time as $\Lambda_{Pl}\sim M^2_{Pl}$, evolves to the present-day allowed value of…

高能物理 - 唯象学 · 物理学 2016-09-01 J. Lopez , D. Nanopoulos

It is well-known that quantum field theory (QFT) induces a huge value of the cosmological constant, $\Lambda$, which is outrageously inconsistent with cosmological observations. We review here some aspects of this fundamental theoretical…

广义相对论与量子宇宙学 · 物理学 2022-07-19 Joan Sola Peracaula

The dynamical effect of the cosmological constant $\Lambda$ on a single spherical void evolving in a the universe is investigated within a non linear perturbation of Newton-Friedmann models. The void expands with a huge initial burst which…

广义相对论与量子宇宙学 · 物理学 2010-11-23 Henri-Hugues Fliche , Roland Triay

The paper deals with the scale discrepancy between the observed vacuum energy in cosmology and the theoretical quantum vacuum energy (cosmological constant problem). Here, we demonstrate that Einstein's equation and an analogy to particle…

综合物理 · 物理学 2019-02-08 Christian Henke

The near-zero value of the cosmological constant \Lambda in an equilibrium context may be due to the existence of a self-tuning relativistic vacuum variable q. Here, a cosmological nonequilibrium context is considered with a corresponding…

广义相对论与量子宇宙学 · 物理学 2008-11-26 F. R. Klinkhamer

Evolution of the scale factor a(t) in Friedmann models (those with zero pressure and a constant cosmological term Lambda) is well understood, and elegantly summarized in the review of Felten and Isaacman [Rev. Mod. Phys. 58, 689 (1986)].…

天体物理学 · 物理学 2008-11-26 J. M. Overduin , F. I. Cooperstock

We investigate the evolution of a universe with a decaying cosmological term (vacuum energy) that is assumed to be a function of the scale factor. In this model, while the cosmological term increases to the early universe, the radiation…

天体物理学 · 物理学 2008-11-26 Riou Nakamura , Masa-aki Hashimoto , Kiyotomo Ichiki