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Related papers: Spatial gradients in the cosmological constant

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A large value of the cosmological constant (CC) is induced in the Standard Model (SM) of Elementary Particle Physics because of Spontaneous Symmetry Breaking. To provide a small value of the observable CC one has to introduce the vacuum…

High Energy Physics - Phenomenology · Physics 2009-10-31 Ilya Shapiro , Joan Sola

The old cosmological constant problem is to understand why the vacuum energy is so small; the new problem is to understand why it is comparable to the present mass density. Several approaches to these problems are reviewed. Quintessence…

Astrophysics · Physics 2007-05-23 Steven Weinberg

We are at a specific period of modern cosmology, during which the large increase of the amount of data leads to the idea that the determination of cosmological parameters has been achieved with a rather good precision. There is a large…

Astrophysics · Physics 2017-08-23 A. Blanchard

The remarkable detection of a spatial variation in the fine-structure constant, alpha, from quasar absorption systems must be independently confirmed by complementary searches. In this letter, we discuss how terrestrial measurements of…

Atomic Physics · Physics 2012-09-11 J. C. Berengut , V. V. Flambaum

Persistent evidence for a cosmic hemispherical asymmetry in the temperature field of cosmic microwave background (CMB) as observed by both WMAP as well as PLANCK increases the possibility of its cosmological origin. Presence of this signal…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-28 Suvodip Mukherjee , Pavan K. Aluri , Santanu Das , Shabbir Shaikh , Tarun Souradeep

In the current state of cosmology, where cosmological parameters are being measured to percent accuracy, it is essential to understand all sources of error to high precision. In this paper we present the results of a study of the local…

Cosmology and Nongalactic Astrophysics · Physics 2016-05-26 Io Odderskov , Marco Baldi , Luca Amendola

A range of cosmological observations demonstrate an accelerated expansion of the Universe, and the most likely explanation of this phenomenon is a cosmological constant. Given the importance of understanding the underlying physics, it is…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-07 Karoline Loeve , Kristine Simone Nielsen , Steen H. Hansen

We discuss cosmology based on a Cuscuta-Galileon gravity theory, which preserves just two degrees of freedom. Although there exists no additional degrees of freedom, introduction of a potential of a scalar field changes the dynamics. The…

General Relativity and Quantum Cosmology · Physics 2022-05-17 Kei-ichi Maeda , Sirachak Panpanich

This paper examines a cosmological model of scale-dependent gravity. The gravitational action is taken to be the Einstein-Hilbert term supplemented with a cosmological constant, where the couplings, $G_k$ and $\Lambda_k$, run with the…

General Relativity and Quantum Cosmology · Physics 2024-05-29 Pedro D. Alvarez , Benjamin Koch , Cristobal Laporte , Angel Rincon

The analysis of the dynamics of radial movement in different reference frames used in cosmology is made. Use of different frames leads to the difference in inertial forces resulting in different observable effects. The important effect is…

General Relativity and Quantum Cosmology · Physics 2021-05-05 A. A. Grib , Yu. V. Pavlov

We consider the standard model with local scale invariance. The theory shows exact scale invariance of dimensionally regulated action. We show that massless gauge fields, which may be abelian or non-abelian, lead to vanishing contribution…

High Energy Physics - Phenomenology · Physics 2010-08-19 Pavan K. Aluri , Pankaj Jain , Subhadip Mitra , Sukanta Panda , Naveen K. Singh

We propose a novel explanation for the smallness of the observed cosmological constant (CC). Regions of space with a large CC are short lived and are dynamically driven to crunch soon after the end of inflation. Conversely, regions with a…

High Energy Physics - Phenomenology · Physics 2021-02-03 Itay M. Bloch , Csaba Csáki , Michael Geller , Tomer Volansky

Increasing improvements in the independent determinations of the Hubble constant and the age of the universe now seem to indicate that we need a small non-vanishing cosmological constant to make the two independent observations consistent…

High Energy Physics - Phenomenology · Physics 2009-10-28 Anupam Singh

The results of different analyses of the dynamical parameters of the Universe are converging towards agreement. Remaining disagreements reflect systematic errors coming either from the observations or from differences in the methods of…

Astrophysics · Physics 2007-05-23 Matts Roos , S. M. Harun-or-Rashid

The tensions between the values of Hubble constant obtained from the early and the late Universe data pose a significant challenge to modern cosmology. Possible modifications of the flat homogeneous isotropic cosmological {\Lambda}CDM model…

Cosmology and Nongalactic Astrophysics · Physics 2021-10-14 S. L. Parnovsky

We review astrophysical, cosmological and terrestrial evidence for and against the constancy of fundamental parameters of particle physics, and discuss theoretical issues of unification and scalar-mediated forces, finding that the current…

High Energy Physics - Phenomenology · Physics 2008-11-26 Thomas Dent

Observations conducted over the last few decades show that the expansion of the Universe is accelerating. In the standard model of cosmology, this accelerated expansion is attributed to a dark energy in the form of a cosmological constant.…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-22 Joseph Ryan

Review of recent works devoted to the temporal and spatial variation of the fundamental constants and dependence of the fundamental constants on the gravitational potential (violation of local position invariance) is presented. We discuss…

Nuclear Theory · Physics 2009-08-18 V. V. Flambaum

Theoretical and observational challenges to standard cosmology such as the cosmological constant problem and tensions between cosmological model parameters inferred from different observations motivate the development and search of new…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-30 Lucas Lombriser

The lensing effect of curved space, which can cause the angular diameter of a fixed reference length seen on the sky to reach a minimum and then increase with redshift, depends sensitively on the value of the cosmological constant,…

High Energy Physics - Phenomenology · Physics 2009-10-22 Lawrence M. Krauss , David Schramm