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The simplest inflationary models predict a primordial power spectrum (PPS) of the curvature fluctuations that can be described by a power-law function that is nearly scale-invariant. It has been shown, however, that the low-multipole…

Cosmology and Nongalactic Astrophysics · Physics 2016-05-25 Eleonora Di Valentino , Stefano Gariazzo , Martina Gerbino , Elena Giusarma , Olga Mena

We perform a cosmological analysis in which we allow the primordial power spectrum of scalar perturbations to assume a shape that is different with respect to the usual power-law, arising from the simplest models of cosmological inflation.…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-22 Stefano Gariazzo

We investigate how inflation model selection is affected by the presence of additional free-streaming relativistic degrees of freedom, i.e. dark radiation. We perform a full Bayesian analysis of both inflation parameters and cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2017-02-07 Thomas Tram , Robert Vallance , Vincent Vennin

The prediction of a nearly scale-invariant spectrum of curvature and tensor fluctuations is among the main features of cosmic inflation. The current measurements of the primordial fluctuations in the cosmic microwave background (CMB)…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-30 Marcos A. G. Garcia , Aline Pereyra-Flores

We study the power spectrum of the mass density perturbations in an inflation scenario that includes thermal dissipation. We show that the condition on which the thermal fluctuations dominate the primordial density perturbations can easily…

Astrophysics · Physics 2009-10-31 Wolung Lee , Li-Zhi Fang

The most stringent bounds on the absolute neutrino mass scale come from cosmological data. These bounds are made possible because massive relic neutrinos affect the expansion history of the universe and lead to a suppression of matter…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-07 Roland de Putter , Eric V. Linder , Abhilash Mishra

We perform a cosmological analysis in which we allow the primordial power spectrum of scalar perturbations to assume a shape that is different from the usual power-law predicted by the simplest models of cosmological inflation. We…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 S. Gariazzo , C. Giunti , M. Laveder

The primordial power spectrum of matter density perturbations contains highly valuable information about new fundamental physics, in particular cosmological inflation, but is only very weakly constrained observationally for small…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-09 Torsten Bringmann , Djuna Croon , Sergio Sevillano Muñoz

We present cosmological bounds on the thermal axion mass in an extended cosmological scenario in which the primordial power spectrum of scalar perturbations differs from the usual power-law shape predicted by the simplest inflationary…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-10 Eleonora Di Valentino , Stefano Gariazzo , Elena Giusarma , Olga Mena

We investigate the possibility that the amplitude of scalar density perturbations may be damped after inflation. This would imply that CMB anisotropies do not uniquely fix the amplitude of the perturbations generated during inflation and…

Astrophysics · Physics 2009-11-11 N. Bartolo , Edward W. Kolb , A. Riotto

If inflation scale is high, light scalars acquire large quantum fluctuations during inflation.If sufficiently long-lived, they will give rise to CDM isocurvature perturbations, which are highly constrained by the Planck data. Focusing on…

High Energy Physics - Phenomenology · Physics 2015-06-19 Masahiro Kawasaki , Naoya Kitajima , Fuminobu Takahashi

Cosmological inflation generates primordial density perturbations on all scales, including those far too small to contribute to the cosmic microwave background. At these scales, isolated ultracompact minihalos of dark matter can form well…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-21 Grigor Aslanyan , Layne C. Price , Jenni Adams , Torsten Bringmann , Hamish A. Clark , Richard Easther , Geraint F. Lewis , Pat Scott

Axion fluctuations generated during inflation lead to isocurvature and non-Gaussian temperature fluctuations in the cosmic microwave background radiation. Following a previous analysis for the model independent string axion we consider the…

High Energy Physics - Theory · Physics 2008-11-26 Ben Kain

Thermal inflation is a second epoch of exponential expansion at typical energy scales $V^{1/4} \sim 10^{6 \sim 8} \mathrm{GeV}$. If the usual primordial inflation is followed by thermal inflation, the primordial power spectrum is only…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-09 Kihyun Cho , Sungwook E. Hong , Ewan D. Stewart , Heeseung Zoe

Thermal inflation, a brief low energy inflation after the primordial inflation, resolves the moduli problem in the context of supersymmetric cosmology. In the thermal inflation scenario, the primordial power spectrum is modestly redshifted…

Cosmology and Nongalactic Astrophysics · Physics 2020-02-14 Heeseung Zoe

Inflationary cosmology provides a natural mechanism for the generation of primordial perturbations which seed the formation of observed cosmic structure and lead to specific signals of anisotropy in the cosmic microwave background…

Astrophysics · Physics 2011-07-19 Salman Habib , Andreas Heinen , Katrin Heitmann , Gerard Jungman

We study thermally induced density perturbations during inflation. This scenario is characterized by two thermodynamical conditions: (1) The primordial perturbations originate in the epoch when the inflationary universe contains a…

Astrophysics · Physics 2009-10-30 Wolung Lee , Li-Zhi Fang

A short introduction to structure formation is given, followed by a discussion of the possible characteristics of the initial perturbations assuming a generic inflationary origin. Observational data related to large-scale structure and the…

Astrophysics · Physics 2014-10-13 Pedro Viana

The standard inflationary model presents a simple scenario within which the homogeneity, isotropy and flatness of the universe appear as natural outcomes and, in addition, fluctuations in the energy density are originated during the…

Astrophysics · Physics 2023-03-08 E. Martinez-Gonzalez , P. Vielva

Perturbations from inflation evolve into large scale structure of the late universe, and encode abundant cosmic structure formation physics. We allow freedom in the primordial power spectrum, rather than assuming a power law scale…

Cosmology and Nongalactic Astrophysics · Physics 2020-05-12 Guilherme Brando , Eric V. Linder
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