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Related papers: Embedding Dark Energy in Supergravity

200 papers

We review some modified gravity models which describe the gravitational dark energy and the possibility of cosmic speed-up. The new consistent version of such theory which contains inverse and HD curvature terms as well as new type of…

High Energy Physics - Theory · Physics 2009-09-17 Shin'ichi Nojiri , Sergei D. Odintsov

Quadratic curvature Gauss-Bonnet gravity may be the solution to the dark energy problem, but a large coupling strength is required. This can lead to conflict with laboratory and planetary tests of Newton's law, as well as light bending. The…

High Energy Physics - Theory · Physics 2008-11-26 Stephen C. Davis

In this brief review I consider the advances made in weak gravitational lensing over the last 8 years, concentrating on the large scales - cosmic shear. I outline the theoretical developments, observational status, and the challenges which…

Astrophysics · Physics 2015-05-13 Alan Heavens

This work summarises some of the attempts to explain the phenomenon of dark energy as an effective description of complex gravitational physics and the proper interpretation of observations. Cosmological backreaction has been shown to be…

Cosmology and Nongalactic Astrophysics · Physics 2010-03-17 Dominik J. Schwarz

We focus on the analysis of three inequivalent equations of state of geometric dark energy in $f(R)$ cosmology that have been considered in the past and discuss their differences, advantages and drawbacks.

General Relativity and Quantum Cosmology · Physics 2015-06-18 Luisa G. Jaime , Leonardo Patiño , Marcelo Salgado

By relaxing the conventional assumption of a purely gravitational interaction between dark energy and dark matter, substantial alterations to the growth of cosmological structure can occur. In this work we focus on the homogeneous transfer…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-08 Fergus Simpson , Brendan M. Jackson , John A. Peacock

A six parameter cosmological model, involving a vacuum energy density that is extremely tiny compared to fundamental particle physics scales, describes a large body of increasingly accurate astronomical data. In a first part of this brief…

High Energy Physics - Phenomenology · Physics 2009-11-11 Norbert Straumann

It has been only ~15 years since the discovery of dark energy (although some may argue there were strong indications even earlier). In the short time since measurements of type Ia supernovae indicated an accelerating universe, many other…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 Tamara M. Davis

After a brief introduction to neutrino electromagnetic properties we focus on the most important constraints on neutrino magnetic moments, charge radii and millicharges from the terrestrial experiments and astrophysical considerations. The…

High Energy Physics - Phenomenology · Physics 2020-09-04 Alexander Studenikin

We propose a supersymmetric extension of the dynamical dark energy function and the corresponding scalar (super)potential in F(R) supergravity. Our model is viable in the Einstein approximation, and also has an analytic (regular)…

High Energy Physics - Theory · Physics 2012-12-27 Sergei V. Ketov , Natsuki Watanabe

We present a short overview of the structure and couplings of supergravity theories at the component level. We do so with as little technical machinery as possible, working directly with the physical on-shell fields and using explicit…

High Energy Physics - Theory · Physics 2023-02-16 Gianguido Dall'Agata , Marco Zagermann

The problem of explaining the acceleration of the expansion of the universe and the observational and theoretical difficulties associated with dark matter and dark energy are discussed. The possibility that Einstein gravity does not…

Astrophysics · Physics 2007-05-23 J. W. Moffat

In this paper we show that a recent attempt to derive dark energy as an entropic force suffers from the same problems as earlier attempts motivated by holography. The possible remedy is again the introduction of source terms.

High Energy Physics - Theory · Physics 2010-03-04 Ulf H. Danielsson

Recent measurements suggest our universe has a substantial dark energy component, which is usually interpreted in terms of a cosmological constant. Here we examine how much the form of this dark energy can be modified while still retaining…

High Energy Physics - Phenomenology · Physics 2009-11-07 Duane A. Dicus , Wayne W. Repko

The accelerated expansion of the Universe is one of the main discoveries of the past decades, indicating the presence of an unknown component: the dark energy. Evidence of its presence is being gathered by a succession of observational…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-13 V. Motta , Miguel A. García-Aspeitia , A. Hernández-Almada , J. Magaña , Tomás Verdugo

Theories with dark forces and dark sectors are of interest for dark matter models. In this paper we find the region in parameter space that is constrained by supernova cooling constraints when the models include dark sector particles with…

High Energy Physics - Phenomenology · Physics 2014-05-21 Herbert K. Dreiner , Jean-François Fortin , Christoph Hanhart , Lorenzo Ubaldi

We study the dynamical properties and space distribution of dark energy in the weak and strong gravitational fields caused by inhomogeneities of matter in the static world of galaxies and clusters. We show that the dark energy in the weak…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-17 B. Novosyadlyj , Yu. Kulinich , M. Tsizh

Astrophysical observations are pointing out huge amounts of dark matter and dark energy needed to explain the observed large scale structures and cosmic accelerating expansion. Up to now, no experimental evidence has been found, at…

Astrophysics · Physics 2009-11-11 S. Capozziello , V. F. Cardone , A. Troisi

Starlight in the Universe impedes the passage of high energy (e.g. TeV) gamma rays due to positron-electron pair production. The history of this stellar radiation field depends upon observations of star formation rate which themselves can…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Malcolm Fairbairn

In this talk, we give a glimpse of the problems with quantum gravity and some possible solutions.

General Relativity and Quantum Cosmology · Physics 2013-09-05 Ricardo Paszko
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