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In the no-scale supergravity global symmetries protect local supersymmetry and a zero value for the cosmological constant. The breakdown of these symmetries, which ensures the vanishing of the vacuum energy density, results in a set of…

High Energy Physics - Phenomenology · Physics 2015-05-14 C. D. Froggatt , R. Nevzorov , H. B. Nielsen

It is well known that global symmetries protect local supersymmetry and a zero value for the cosmological constant in no--scale supergravity. A particular breakdown of these symmetries, which ensures the vanishing of the vacuum energy…

High Energy Physics - Theory · Physics 2008-10-17 C. D. Froggatt , R. Nevzorov , H. B. Nielsen

In no--scale supergravity global symmetries protect local supersymmetry and a zero value for the cosmological constant. We consider the breakdown of these symmetries and present a minimal SUGRA model motivated by the multiple point…

High Energy Physics - Phenomenology · Physics 2009-11-11 C. Froggatt , R. Nevzorov , H. B. Nielsen

The tiny order of magnitude of the cosmological constant is sought to be explained in a model involving the following ingredients: supersymmetry breaking in N=1 supergravity and the multiple point principle. We demonstrate the viability of…

High Energy Physics - Phenomenology · Physics 2011-07-19 C. Froggatt , L. Laperashvili , R. Nevzorov , H. B. Nielsen

We review symmetries protecting a zero value for the cosmological constant in no--scale supergravity and reveal the connection between the Multiple Point Principle, no--scale and superstring inspired models.

High Energy Physics - Phenomenology · Physics 2007-05-23 C. Froggatt , L. Laperashvili , R. Nevzorov , H. B. Nielsen

It is well known that global symmetries protect local supersymmetry and a zero value for the cosmological constant in no--scale supergravity. The breakdown of these symmetries, which ensure the vanishing of the vacuum energy density,…

High Energy Physics - Phenomenology · Physics 2011-04-22 C. Froggatt , R. Nevzorov , H. B. Nielsen

We study the cosmological evolution of the universe when quintessence is modeled within supergravity, supersymmetry is broken in a hidden sector, and we also include observable matter in a third independent sector. We find that the presence…

Astrophysics · Physics 2009-11-11 Philippe Brax , Jerome Martin

There are many theories of quantum gravity, depending on asymptotic boundary conditions, and the amount of supersymmetry. The cosmological constant is one of the fundamental parameters that characterize different theories. If it is…

High Energy Physics - Theory · Physics 2015-06-26 T. Banks

In spontaneously broken supergravity with non-flat potential the vanishing of the cosmological constant is usually associated with a non-trivial balancing of two opposite-sign contributions. We make the simple observation that, in an…

High Energy Physics - Theory · Physics 2009-02-20 A. Hebecker

The empirical mass of the Higgs boson suggests small to vanishing values of the quartic Higgs self--coupling and the corresponding beta function at the Planck scale, leading to degenerate vacua. This leads us to suggest that the measured…

High Energy Physics - Phenomenology · Physics 2015-06-19 C. D. Froggatt , R. Nevzorov , H. B. Nielsen , A. W. Thomas

We argue that the exact degeneracy of vacua in N=1 supergravity can shed light on the smallness of the cosmological constant. The presence of such vacua, which are degenerate to very high accuracy, may also result in small values of the…

High Energy Physics - Phenomenology · Physics 2015-10-20 C. Froggatt , R. Nevzorov , H. B. Nielsen , A. Thomas

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 paper aims to provide an explanation for the tiny value of the cosmological constant and the low vacuum energy density to represent the dark energy. To accomplish this, we will search for a fundamental principle of symmetry in…

General Relativity and Quantum Cosmology · Physics 2016-11-14 Cláudio Nassif

In this essay, we present a new understanding of the cosmological constant problem, built upon the realization that the vacuum energy density can be expressed in terms of a phase space volume. We introduce a UV-IR regularization which…

High Energy Physics - Theory · Physics 2023-03-31 Laurent Freidel , Jerzy Kowalski-Glikman , Robert G. Leigh , Djordje Minic

$CP$ violating effects in the Minimal Supersymmetric Standard Model (MSSM) can lead to excessively large contributions to the neutron EDM (\dn). We write criteria which ensure that the low energy supergravity (SUGRA) parametrization of the…

High Energy Physics - Phenomenology · Physics 2010-11-01 Robert Garisto

We will look for an implementation of new symmetries in the space-time structure and their cosmological implications. This search will allow us to find a unified vision for electrodynamics and gravitation. We will attempt to develop a…

General Physics · Physics 2011-11-10 Claudio Nassif

The idea of the quantum state of the Universe described by some density matrix, i.e mixture of at least two vacua, the trivial symmetric and the nontrivial one with spontaneously broken symmetry is discussed. Nonzero cosmological constant…

General Relativity and Quantum Cosmology · Physics 2007-05-23 A. A. Grib

We consider a scalar field with a bottom-less potential, such as $g^3 \phi$, finding that cosmologies unavoidably end up with a crunch, late enough to be compatible with observations if $g \lesssim 1.2 H_0^{2/3} M_{\rm Pl}^{1/3}$. If…

General Relativity and Quantum Cosmology · Physics 2019-09-09 Alessandro Strumia , Daniele Teresi

We present a new cosmological model of the Universe based on the two discoveries: 1. cosmological constant is very small, and 2. Nature shows a new law in physics called "Multiple Point Principle" (MPP). The MPP predicts the two degenerate…

High Energy Physics - Phenomenology · Physics 2018-01-30 B. G. Sidharth , C. R. Das , C. D. Froggatt , H. B. Nielsen , Larisa Laperashvili

We generalize the standard model of particle physics such it displays global scale invariance. The gravitational action is also suitably modified such that it respects this symmetry. This model is interesting since the cosmological constant…

Astrophysics · Physics 2009-06-23 Pankaj Jain , Subhadip Mitra , Naveen K. Singh
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