English
Related papers

Related papers: Large Gravitational Waves and Lyth Bound in Multi …

200 papers

Large field inflation models are favored by the recent BICEP2 that has detected gravitational wave modes generated during inflation. We study general large field inflation models for which the potential contains (constant) quadratic and…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-28 Tatsuo Kobayashi , Osamu Seto

Inspired by the chromo-natural inflation model of Adshead&Wyman, we reshape its scalar content to relax the tension with current observational bounds. Besides an inflaton, the setup includes a spectator sector in which an axion and SU(2)…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-18 Emanuela Dimastrogiovanni , Matteo Fasiello , Tomohiro Fujita

A scenario with two subsequent periods of inflationary expansion in the very early universe is examined. The model is based on a potential motivated by symmetries being found in field theory at high energy. For various parameter sets of the…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-13 Simon Schettler , Jurgen Schaffner-Bielich

We analyse the implications for inflationary models of the cosmic microwave background (cmb) anisotropy measured by COBE. Vacuum fluctuations during inflation generate an adiabatic density perturbation, and also gravitational waves. The…

Astrophysics · Physics 2009-10-22 David H Lyth , Andrew R Liddle

Within the context of the cold dark matter model, current observations suggest that inflationary models which generate a tilted primordial power spectrum with negligible gravitational waves provide the most promising mechanism for…

Astrophysics · Physics 2015-06-24 James E. Lidsey

With an energy scale that can be as high as $10^{14}\,{\rm GeV}$, inflation may provide a unique probe of high-energy physics. Both scalar and tensor fluctuations generated during this early accelerated expansion contain crucial information…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-25 Laura Iacconi , Matteo Fasiello , Hooshyar Assadullahi , Emanuela Dimastrogiovanni , David Wands

We determine the frequency of regions of small-field inflation in the Wigner landscape as an approximation to random supergravities/type IIB flux compactifications. We show that small-field inflation occurs exponentially more often than…

High Energy Physics - Theory · Physics 2015-06-15 Francisco G. Pedro , Alexander Westphal

The effective approach is applied to the analysis of inflationary magnetogenesis. Rather than assuming a particular underlying description, all the generally covariant terms potentially appearing with four space-time derivatives in the…

High Energy Physics - Theory · Physics 2021-07-15 Massimo Giovannini

The inflationary paradigm provides a robust description of the peculiar initial conditions which are required for the success of the Hot Big Bang model of cosmology, as well as of the recent precision measurements of temperature…

High Energy Physics - Theory · Physics 2008-11-26 C. P. Burgess

We discuss inflation in models with large extra dimensions, driven by a bulk scalar field. The brane inflaton is then a single effective field, obtained from the bulk scalar field by scaling. The self interaction terms of the effective…

High Energy Physics - Phenomenology · Physics 2008-11-26 R. N. Mohapatra , A. Pérez-Lorenzana , C. A. de S. Pires

The no-boundary wave function of quantum gravity usually assigns only very small probability to long periods of inflation. This was a reason to doubt about the no-boundary wave function to explain the observational universe. We study the…

General Relativity and Quantum Cosmology · Physics 2013-10-09 Dong-il Hwang , Soo A Kim , Bum-Hoon Lee , Hanno Sahlmann , Dong-han Yeom

It is investigated if predictions of the inflationary scenario regarding spectra of scalar and tensor perturbations generated from quantum vacuum fluctuations are robust with respect to a modification of the dispersion law for frequencies…

Astrophysics · Physics 2008-11-26 A. A. Starobinsky

If inflation was preceded by a radiation era then at the time of inflation there will exist a decoupled thermal distribution of gravitons. Gravitational waves generated during inflation will be amplified by the process of stimulated…

Astrophysics · Physics 2008-11-26 Kaushik Bhattacharya , Subhendra Mohanty , Akhilesh Nautiyal

We present the first attempt to use a combination of CMB, LIGO, and PPTA data to constrain both the tilt and the running of primordial tensor power spectrum through constraints on the gravitational wave energy density generated in the early…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 P. Daniel Meerburg , Renée Hložek , Boryana Hadzhiyska , Joel Meyers

It is proposed that if quantum states of space-time are coherent on null surfaces, holographic Planck-scale fluctuations of inflationary horizons dominate the formation of primordial scalar curvature perturbations. It is shown that the…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-17 Craig Hogan

In most current models of inflation based on a weakly self-coupled scalar matter field minimally coupled to gravity, the period of inflation lasts so long that, at the beginning of the inflationary period, the physical wavelengths of…

High Energy Physics - Theory · Physics 2008-11-26 Jerome Martin , Robert H. Brandenberger

If an adiabatic density perturbation is responsible for large scale structure and the cmb anisotropy, its spectral index $n$ will be measured in the forseeable future with an accuracy $\Delta n\sim .01$. This is precisely the kind of…

High Energy Physics - Phenomenology · Physics 2016-09-06 David H. Lyth

Higgs inflation can occur if the Standard Model (SM) is a self-consistent effective field theory up to inflationary scale. This leads to a lower bound on the Higgs boson mass, $M_h \geq M_{\text{crit}}$. If $M_h$ is more than a few hundreds…

High Energy Physics - Phenomenology · Physics 2015-06-19 Fedor Bezrukov , Mikhail Shaposhnikov

Supersolid inflation is a class of inflationary theories that simultaneously breaks time and space reparameterization invariance during inflation, with distinctive features for the dynamics of cosmological fluctuations. We investigate…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-19 Angelo Ricciardone , Gianmassimo Tasinato

We investigate the generation of gravitational waves in the hybrid quintessential inflationary model. The full gravitational-wave energy spectrum is calculated using the method of continuous Bogoliubov coefficients. The post-inflationary…

General Relativity and Quantum Cosmology · Physics 2015-03-13 Paulo M. Sá , Alfredo B. Henriques
‹ Prev 1 8 9 10 Next ›