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Related papers: Cosmic Inflation and Genetic Algorithms

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We reconsider the toy-model of topological inflation, based on the R*4-modified gravity. By using its equivalence to the certain scalar-tensor gravity model in four space-time dimensions, we compute the inflaton scalar potential and…

High Energy Physics - Theory · Physics 2011-01-11 S. Kaneda , S. V. Ketov , N. Watanabe

Models of axion inflation based on a single cosine potential require the axion decay constant $f$ to be super-Planckian in size. However, $f > M_{Pl}$ is disfavored by the Weak Gravity Conjecture (WGC). It is then pertinent to ask if one…

High Energy Physics - Phenomenology · Physics 2019-06-10 Pran Nath , Maksim Piskunov

An early stage of kinetic energy domination for inflation is applied to single-field quadratic and hybrid-type potentials considering only the amount of inflation necessary to solve the problems of the standard cosmological scenario. Using…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-27 Erandy Ramirez

Motivated by machine learning, we introduce a novel method for randomly generating inflationary potentials. Namely, we treat the Taylor coefficients of the potential as weights in a single-layer neural network and use gradient ascent to…

High Energy Physics - Theory · Physics 2019-02-27 Tom Rudelius

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

We study the ultra slow roll model in the context of stochastic inflation. Using stochastic $\delta N$ formalism, we calculate the mean number of $e$-folds, the power spectrum, the bispectrum and the stochastic corrections into these…

High Energy Physics - Theory · Physics 2019-01-23 Hassan Firouzjahi , Amin Nassiri-Rad , Mahdiyar Noorbala

We implement Slow Roll Reconstruction -- an optimal solution to the inverse problem for inflationary cosmology -- within ModeCode, a publicly available solver for the inflationary dynamics. We obtain up-to-date constraints on the…

Cosmology and Nongalactic Astrophysics · Physics 2012-07-10 Jorge Noreña , Christian Wagner , Licia Verde , Hiranya V. Peiris , Richard Easther

The scalar-tensor Dirac-Born-Infeld (DBI) inflation scenario provides a simple mechanism to reduce the large values of the boost factor associated with single field models with DBI action, whilst still being able to drive 60 efolds of…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-04 Joel M. Weller , Carsten van de Bruck , David F. Mota

Combination of Plank and BICEP2 data reported that tensor to scalar ratio $r\simeq 0.16$ and scalar spectral index $n_{s}\simeq 0.96$. In this short note, it is shown that chaotic inflation with quadratic potential, which perfectly accounts…

High Energy Physics - Phenomenology · Physics 2015-02-25 Sibo Zheng

The form of the inflationary potential is severely restricted if one requires that it be natural in the technical sense, i.e. terms of unrelated origin are not required to be correlated. We determine the constraints on observables that are…

Astrophysics · Physics 2010-01-30 Shaun Hotchkiss , Gabriel German , Graham G Ross , Subir Sarkar

We briefly review several Higgs inflation models and discuss their cosmological implications. We first classify the inflation models according to the predicted value of the tensor-to-scalar ratio: (i) $r = {\cal O}(0.01-0.1)$, (ii) $r =…

High Energy Physics - Phenomenology · Physics 2015-06-01 Fuminobu Takahashi

We reexamine inflation due to a constrained inflaton in the model of a complex scalar. Inflaton evolves along a spiral-like valley of special scalar potential in the scalar field space just like single field inflation. Sub-Planckian…

High Energy Physics - Phenomenology · Physics 2015-12-02 Romy H. S. Budhi , Shoichi Kashiwase , Daijiro Suematsu

A four-dimensional universe, arising from a flux compactification of Type IIB string theory, contains scalar fields with a potential determined by topological and geometric parameters of the internal -hidden- dimensions. We show that…

Astrophysics · Physics 2007-05-23 Joan Simon , Raul Jimenez , Licia Verde , Per Berglund , Vijay Balasubramanian

The increasingly stringent observational bounds on primordial gravitational waves strongly constrain inflationary model building, favoring scenarios that predict highly suppressed tensor perturbations. While many viable constructions rely…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-11 Panagiotis G. Stavros , Spyros Basilakos , Emmanuel N. Saridakis

We develop analytic and numerical techniques for studying the statistics of slow-roll inflation in random Gaussian landscapes. As an illustration of these techniques, we analyze small-field inflation in a one-dimensional landscape. We…

High Energy Physics - Theory · Physics 2017-06-14 Ali Masoumi , Alexander Vilenkin , Masaki Yamada

In models like axion monodromy, temporal features during inflation which are not associated with its ending can produce scalar, and to a lesser extent, tensor power spectra where deviations from scale-free power law spectra can be as large…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-31 Hayato Motohashi , Wayne Hu

The value of the tensor-to-scalar ratio $r$ in the region allowed by the latest $Planck$ 2015 measurements can be associated to a large variety of inflationary models. We discuss here the potential of future Cosmic Microwave Background…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-17 Miguel Escudero , Héctor Ramírez , Lotfi Boubekeur , Elena Giusarma , Olga Mena

Inflation occurring at energy densities less than (10$^{14}$ GeV)$^4$ produces tensor perturbations too small to be measured by cosmological surveys. However, we show that it is possible to probe low scale inflation by measuring the mass of…

High Energy Physics - Phenomenology · Physics 2016-12-14 Joseph Bramante , Jessica Cook , Antonio Delgado , Adam Martin

In cosmic inflation driven by a scalar gauge singlet field with a tree level Higgs potential, the scalar to tensor ratio r is estimated to be larger than 0.036, provided the scalar spectral index n_s >= 0.96. We discuss quantum smearing of…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-28 Mansoor Ur Rehman , Qaisar Shafi

We study the implications of the recently proposed Trans-Planckian Censorship Conjecture (TCC) for early universe cosmology and in particular inflationary cosmology. The TCC leads to the conclusion that if we want inflationary cosmology to…

High Energy Physics - Theory · Physics 2020-05-06 Alek Bedroya , Robert Brandenberger , Marilena Loverde , Cumrun Vafa
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