English
Related papers

Related papers: Concern Regarding "A Non-Inflationary Solution to …

200 papers

A finite quantum gravity theory is used to resolve the cosmological constant problem. A fundamental quantum gravity scale, \Lambda_G \leq 10^{-3} eV, is introduced above which the quantum corrections to the vacuum energy density coupled to…

High Energy Physics - Phenomenology · Physics 2007-05-23 J. W. Moffat

We propose a new class of inflationary solutions to the standard cosmological problems (horizon, flatness, monopole,...), based on a modification of old inflation. These models do not require a potential which satisfies the normal…

High Energy Physics - Theory · Physics 2007-05-23 Gia Dvali , Shamit Kachru

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

To explain the accelerated expansion of late universe, the 1/R correction to Einstein gravity is usually considered, where R is the Ricci scalar. This correction term is generally believed to be negligible in the early universe. However, if…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Shi Pi , Tower Wang

A scale-invariant universe can have a period of accelerated expansion at early times: inflation. We use a frame-invariant approach to calculate inflationary observables in a scale invariant theory of gravity involving two scalar fields -…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-26 Pedro G. Ferreira , Christopher T. Hill , Johannes Noller , Graham G. Ross

Theories with ingredients like the Higgs mechanism, gravitons, and inflaton fields rejuvenate the idea that relativistic kinematics is dynamically emergent. Eternal inflation treats the Hubble constant H as depending on location.…

General Relativity and Quantum Cosmology · Physics 2015-05-19 Sascha Vongehr

We study quintessential inflation using a generalized exponential potential $V(\phi)\propto exp(-\lambda \phi^n/Mpl^n), n>1$, the model admits slow-roll inflation at early times and leads to close-to-scaling behaviour in the post…

General Relativity and Quantum Cosmology · Physics 2017-06-21 Chao-Qiang Geng , Chung-Chi Lee , M. Sami , Emmanuel N. Saridakis , Alexei A. Starobinsky

An anthropic understanding of the cosmological constant requires that the vacuum energy at late time scans from one patch of the universe to another. If the vacuum energy during inflation also scans, the various patches of the universe…

High Energy Physics - Theory · Physics 2014-11-18 Brian Feldstein , Lawrence J. Hall , Taizan Watari

A Gauss-Bonnet term naturally appears in the action for gravity when one considers the existence of space time with dimensions more than 1+3. A variety of inflationary models can be obtained within such a framework, once the scale factor…

General Relativity and Quantum Cosmology · Physics 2013-02-19 Isha Pahwa , Debajyoti Choudhury , T. R. Seshadri

We generalise Einstein's formulation of the traceless Einstein equations to $f(R)$ gravity theories. In the case of the vacuum traceless Einstein equations, we show that a non-constant Weyl tensor leads via a conformal transformation to a…

General Relativity and Quantum Cosmology · Physics 2020-09-15 John D. Barrow , Spiros Cotsakis

Modern cosmology presents important challenges such as the \textit{Hubble tension}, \textit{El Gordo's collision} or the \textit{impossible galaxies} ($z > 10$). Slight modifications to the standard model propose new parameters (e.g. the…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-19 Robert Monjo

We present a minimal cosmological solution to the hierarchy problem. Our model consists of a light pseudoscalar and an extra Higgs doublet in addition to the field content of the Standard Model. We consider a landscape of vacua with varying…

High Energy Physics - Phenomenology · Physics 2024-07-24 Susobhan Chattopadhyay , Dibya S. Chattopadhyay , Rick S. Gupta

In low scale quantum gravity scenarios the fundamental scale of nature can be as low as TeV, in order to address the naturalness of the electroweak scale. A number of difficulties arise in constructing specific models; stabilisation of the…

High Energy Physics - Phenomenology · Physics 2009-11-07 Anne M Green , Anupam Mazumdar

This article reviews basic construction and cosmological implications of a power-counting renormalizable theory of gravitation recently proposed by Horava. We explain that (i) at low energy this theory does not exactly recover general…

High Energy Physics - Theory · Physics 2010-11-03 Shinji Mukohyama

We investigate cosmological solutions for the modified gravity theory obtained from quantum relative entropy between the metric of spacetime and the metric induced by the geometry and matter fields. The vacuum equations admit inflationary…

General Relativity and Quantum Cosmology · Physics 2025-12-23 Udaykrishna Thattarampilly , Yunlong Zheng

The enigmatic phenomenon of dark energy (DE) is regarded as the elusive entity driving the accelerated expansion of our Universe. A plausible candidate for DE is the non-zero Einstein Cosmological Constant $\Lambda_{E}$ manifested as a…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-05 Vesselin G. Gueorguiev , Andre Maeder

In the present work, we extend and generalize our previous work regarding the scale dependence applied to black holes in the presence of non-linear electrodynamics [1]. The starting point for this study is the Einstein-power-Maxwell theory…

General Relativity and Quantum Cosmology · Physics 2021-02-05 Angel Rincon , Ernesto Contreras , Pedro Bargueño , Benjamin Koch , Grigoris Panotopoulos

The lightest Kaluza-Klein particle appearing in models with universal extra dimensions has recently been proposed as a viable dark matter candidate when the extra dimensions are compactified on a scale of the order of 1 TeV. Underlying…

Astrophysics · Physics 2009-11-07 Torsten Bringmann , Martin Eriksson , Michael Gustafsson

By ignoring the local density fluctuations, we construct an uniform Higgs-field's (inflaton's) quantum theory with varying effective Planck constant ($\hbar_{v}(t) \propto R(t)^{-3}$) for the evolution of the dark energy density during the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Wei Yuan , Yu-xin Liu

The main purpose of this paper is to advance a unified theory of dark matter, dark energy, and inflation first formulated in 2008. Our minimal affine extension of the GR has geodesics coinciding with the pseudo Riemannian ones, up to…

General Relativity and Quantum Cosmology · Physics 2019-07-02 Alexandre T. Filippov