English
Related papers

Related papers: Power spectrum nulls due to non-standard inflation…

200 papers

We study quintessential inflation in the framework of metric-affine gravity. It is well known that non-minimal couplings with the Holst invariant can generate a quasi-pole inflationary behaviour resulting in a Starobinsky-like…

General Relativity and Quantum Cosmology · Physics 2026-03-18 Konstantinos Dimopoulos , Christian Dioguardi , Ioannis D. Gialamas , Antonio Racioppi

Slow-roll inflation may simultaneously solve the horizon problem and generate a near scale-free fluctuation spectrum P(k). These two processes are intimately connected via the initiation and duration of the inflationary phase. But a recent…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-03 Jingwei Liu , Fulvio Melia

The next generation of cosmological observations will be sensitive to small deviations from a pure power law in the primordial power spectrum of the curvature perturbations. In the context of slow-roll inflation, these deviations are…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-15 Pierre Auclair , Christophe Ringeval

The decoherence of quantum fluctuations into classical perturbations during inflation is discussed. A simple quantum mechanical argument, using a spatial particle wavefunction rather than a field description, shows that observable…

Astrophysics · Physics 2007-05-23 Craig J. Hogan

In order to go beyond the mean-field approximation, commonly used in the inflationary computations, an identification of the quantum constituents of the inflationary background is made. In particular, the homogeneous scalar field…

High Energy Physics - Theory · Physics 2017-03-08 Lasha Berezhiani

The standard structure formation scenario is successful on linear scales. Several apparent problems affect it however at galactic scales, such as the small scale problems at low redshift and more recent issues involving early massive galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2020-09-09 Karim H. Seleim , Amr A. El-Zant , A. M. Abdel-Moneim

We identify the effective theory describing inflationary super-Hubble scales and show it to be a special case of effective field theories appropriate to open systems. Open systems allow information to be exchanged between the degrees of…

High Energy Physics - Theory · Physics 2015-09-01 C. P. Burgess , R. Holman , G. Tasinato , M. Williams

We compute the corrections to the primordial power spectrum that should arise in realistic inflationary scenarios if there exists a generic covariant ultraviolet (UV) cutoff, as commonly motivated by considerations of quantum gravity. The…

High Energy Physics - Theory · Physics 2023-05-01 Aidan Chatwin-Davies , Achim Kempf , Petar Simidzija

Motivated by the prospect of testing inflation from precision cosmic microwave background observations, we present analytic results for scalar and tensor perturbations in single-field inflation models based on the application of uniform…

Astrophysics · Physics 2009-11-07 Salman Habib , Katrin Heitmann , Gerard Jungman , Carmen Molina-Paris

Observations of the cosmic microwave background do not yet determine whether inflation was driven by a slowly-rolling scalar field or involved another physical mechanism. In this paper we discuss the prospects of using the power spectra of…

High Energy Physics - Theory · Physics 2015-12-10 Daniel Baumann , Daniel Green , Rafael A. Porto

The inflationary paradigm enjoys a very wide acceptance in the cosmological community, due in large part to the fact that it is said to "naturally account" for a nearly scale independent power primordial spectrum of fluctuations which is in…

General Relativity and Quantum Cosmology · Physics 2011-03-28 Gabriel Leon , Daniel Sudarsky

We study the inflationary evolution of a scalar field $h$ with an unstable potential for the case where the Hubble parameter $H$ during inflation is larger than the instability scale $\Lambda_I$ of the potential. Quantum fluctuations in the…

High Energy Physics - Theory · Physics 2016-03-14 John Kearney , Hojin Yoo , Kathryn M. Zurek

The cosmological observations of cosmic microwave background and large-scale structure indicate that our universe has a nearly scaling invariant power spectrum of the primordial perturbation. However, the exact origin for this primordial…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-21 Qing-Yang Wang , Yong Tang , Yue-Liang Wu

We investigated the evolution of the primordial density perturbations produced by inflation with thermal dissipation. A full relativistic analysis on the evolution of initial perturbations from the warm inflation era to a…

Astrophysics · Physics 2009-10-31 W. L. Lee , L. Z. Fang

We consider models of inflation that contain a transient non-slow-roll stage and investigate the conditions under which a dip appears in the power spectrum of the curvature perturbation. Using the $\delta N$ formalism, we derive a general…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-19 Tomohiro Fujita , Ryodai Kawaguchi , Misao Sasaki , Yuichiro Tada

The predictive power of cosmic inflation hinges on the existence of a conserved quantity at very large scales, called the primordial curvature perturbation, which is therefore insensitive to the details of reheating and the physics of the…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-11 Matteo Braglia , Lucas Pinol

We study the amplitude and spectral tilt of density perturbations in the simplest hybrid inflation models. We give an exact expression for the amplitude of quantum fluctuations on all scales in the limit where we can neglect the…

Astrophysics · Physics 2009-06-19 Juan Garcia-Bellido , David Wands

In addition to generating the appropriate perturbation power spectrum, an inflationary scenario must take into account the need for inflation to end subsequently. In the context of single-field inflation models where inflation ends by…

Astrophysics · Physics 2009-11-10 Michaël Malquarti , Samuel M. Leach , Andrew R. Liddle

Inflationary models that contain a transient ultra-slow-roll phase can exhibit strong non-perturbative dynamics, making the usual perturbative treatment of cosmological fluctuations incomplete. In such regimes, quantum diffusion and the…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-29 Xiao-Quan Ye , Shao-Jiang Wang

We use the delta N-formalism to describe the leading order contributions to the primordial power spectrum, bispectrum and trispectrum in multiple-field models of inflation at leading order in a perturbative expansion. In slow-roll models…

Astrophysics · Physics 2008-11-26 Christian T. Byrnes , Misao Sasaki , David Wands
‹ Prev 1 8 9 10 Next ›