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Related papers: Bispectrum from five-dimensional inflation

200 papers

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

The power spectrum of M-theory cascade inflation is derived. It possesses three distinctive signatures: a decisive power suppression at small scales, oscillations around the scales that cross the horizon when the inflaton potential jumps…

High Energy Physics - Theory · Physics 2007-05-23 Amjad Ashoorioon , Axel Krause

We present a model with a complex and a real scalar fields and a potential whose symmetry is explicitly broken by Planck-scale physics. For exponentially small breaking, the model accounts for the period of inflation in the early universe…

Astrophysics · Physics 2007-05-23 Gabriel Zsembinszki

We describe a general scenario, dubbed "Inflatable Dark Matter", in which the density of dark matter particles can be reduced through a short period of late-time inflation in the early universe. The overproduction of dark matter that is…

High Energy Physics - Phenomenology · Physics 2016-01-27 Hooman Davoudiasl , Dan Hooper , Samuel D. McDermott

The bispectrum will play an important role in future galaxy surveys. On large scales it is a key probe for measuring primordial non-Gaussianity which can help differentiate between different inflationary models and other theories of the…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-12 Chris Clarkson , Eline M. de Weerd , Sheean Jolicoeur , Roy Maartens , Obinna Umeh

The conventional slow-roll approximation is broken in the so-called "ultra slow-roll" models of inflation, for which the inflaton potential is exactly (or extremely) flat. The interesting nature of (canonical) ultra slow-roll inflation is…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-18 Shin'ichi Hirano , Tsutomu Kobayashi , Shuichiro Yokoyama

The large-scale power deficit in the cosmic microwave background fluctuations might be relevant with the physics of pre-inflation, a bounce, or a superinflationary phase preceding slow-roll inflation, which can provide a singular-free…

Cosmology and Nongalactic Astrophysics · Physics 2015-07-15 Yong Cai , Yu-Tong Wang , Yun-Song Piao

We discuss the possibility that we could obtain some hints of the heavy physics during inflation by analyzing local features of the primordial bispectrum. A heavy scalar field could leave large signatures in the primordial spectra through…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-25 Ryo Saito , Yu-ichi Takamizu

We study the evolution of scalar curvature perturbations in a brane-world inflation model in a 5D Anti-de Sitter spacetime. The inflaton perturbations are confined to a 4D brane but they are coupled to the 5D bulk metric perturbations. We…

High Energy Physics - Theory · Physics 2009-02-05 Takashi Hiramatsu , Kazuya Koyama

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

We point out three correlated predictions of the axion monodromy inflation model: large amplitude of gravitational waves, suppression of power on horizon scales and on scales relevant for the formation of dwarf galaxies. While these…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Quinn E. Minor , Manoj Kaplinghat

Enormous information about interactions is contained in the non-Gaussianities of the primordial curvature perturbations, which are essential to break the degeneracy of inflationary models. We study the primordial bispectra for G-inflation…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-21 Fengge Zhang , Yungui Gong , Jiong Lin , Yizhou Lu , Zhu Yi

Quintessential inflation provides a unified description of inflation and dark energy in terms of a single scalar degree of freedom, the cosmon. We present here a comprehensive overview of this appealing paradigm, highlighting its key…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-04 Dario Bettoni , Javier Rubio

We consider an inflationary kinetic function with an integrable pole that is traversed during inflation. This scenario leads to enhanced spectra of primordial scalar inhomogeneities with detectable signals: formation of primordial black…

High Energy Physics - Phenomenology · Physics 2024-06-18 Anish Ghoshal , Alessandro Strumia

It has recently been shown [1] that light vector particles produced from inflationary fluctuations can give rise to the dark matter in the Universe. A similar mechanism has been discussed in [2] for a non-minimally coupled scalar enjoying a…

High Energy Physics - Phenomenology · Physics 2018-10-24 Gonzalo Alonso-Álvarez , Joerg Jaeckel

Quantum diffusion describes the inflow of vacuum quantum fluctuations as they get amplified by gravitational instability, and stretched to large distances during inflation. In this picture, the dynamics of the universe's expansion becomes…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-12 Vincent Vennin , David Wands

In this paper we use the collapse metric obtained by Carneiro and Fabris to calculate the power spectrum associated to gauge invariant fluctuations of the metric during the formation of a primordial scalar black hole at the end of…

General Relativity and Quantum Cosmology · Physics 2024-11-13 José Edgar Madriz Aguilar , J. O. Valle , M. Montes , C. Romero

We study the generation of a large power spectrum, necessary for primordial black hole formation, within the effective theory of single-field inflation. The mechanisms we consider include a transition into a ghost-inflation-like phase and…

High Energy Physics - Theory · Physics 2022-02-02 Guillermo Ballesteros , Sebastián Céspedes , Luca Santoni

Inflection point inflation generically includes a deviation from slow-roll when the inflaton approaches the inflection point. Such deviations are shown to be generated by transitions between singular trajectories. The effects on the power…

High Energy Physics - Theory · Physics 2013-07-22 Sean Downes , Bhaskar Dutta

We examine the spectrum of inflaton fluctuations resulting from any given long period of exponential inflation. Infrared and ultraviolet divergences in the inflaton dispersion summed over all modes do not appear in our approach. We show how…

High Energy Physics - Theory · Physics 2009-11-06 Matthew M. Glenz , Leonard Parker