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Related papers: Computing the Primordial Power Spectra Directly

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In this paper we study the inflation model driven by the phantom field. We propose a possible exit from phantom inflation to our observational cosmology by introducing an additional normal scalar field, similar to hybrid inflation model.…

Astrophysics · Physics 2016-08-30 Yun-Song Piao , Yuan-Zhong Zhang

Until recently our knowledge of the primordial curvature perturbation was relatively modest. Ever since COBE delivered its map of data we know the scalar spectrum of primordial perturbations is approximately flat, with the power being only…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-24 Raquel H. Ribeiro

We investigate the ability of current CMB data to reliably constrain the form of the primordial power spectrum generated during inflation. We attempt to identify more exotic power spectra that yield equally good fits to the data as simple…

Astrophysics · Physics 2009-06-23 Brian A. Powell , William H. Kinney

We explore the effect of initial conditions on the inflationary wavefunction and their consequences for the observed spectrum of primordial fluctuations. In a class of models with a sudden transition into inflation we find that, for a…

High Energy Physics - Theory · Physics 2015-05-30 Daniel Carney , Willy Fischler , Sonia Paban , Navin Sivanandam

Recently there have been differing viewpoints on how to evaluate the curvature power spectrum generated during inflation. Since the primordial curvature power spectrum is the seed for structure formation and provides a link between…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-06 Mar Bastero-Gil , Arjun Berera , Namit Mahajan , Raghavan Rangarajan

We study the generation of primordial fluctuations in pure de Sitter inflation where the quantum scalar field dynamics are governed by polymer (not Schrodinger) quantization. This quantization scheme is related to, but distinct from, the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Sanjeev S. Seahra , Iain A. Brown , Golam Mortuza Hossain , Viqar Husain

We build upon previous analytical treatments of scalar perturbations in curved inflationary universes to obtain analytical templates for the primordial tensor power spectrum in models with non-zero primordial spatial curvature. These…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-27 Ezra Msolla , Ayngaran Thavanesan

It has been suggested that the effects of renormalization significantly reduce the amplitude of the inflationary spectra at scales measurable in the cosmic microwave background. Via a gauge-invariant analysis, we compute the renormalized…

General Relativity and Quantum Cosmology · Physics 2024-08-06 Silvia Pla , Ben A. Stefanek

We investigate the enhancement of the power spectra large enough to produce primordial black holes in models with multiple scalar fields. We present analytic solutions for the perturbations in the case of constant turns without the need for…

High Energy Physics - Theory · Physics 2024-09-12 Perseas Christodoulidis , Jinn-Ouk Gong

We investigate the origin and evolution of primordial electric and magnetic fields in the early universe, when the expansion is governed by a cosmological constant $\Lambda_0$. Using the gravitoelectromagnetic inflationary formalism with…

General Relativity and Quantum Cosmology · Physics 2009-04-06 Federico Agustin Membiela , Mauricio Bellini

We derive analytic bounds on the shape of the primordial power spectrum in the context of single-field inflation. In particular, the steepest possible growth has a spectral index of $n_s - 1 = 4$ once transients have died down. Its primary…

Cosmology and Nongalactic Astrophysics · Physics 2019-06-24 Christian T. Byrnes , Philippa S. Cole , Subodh P. Patil

We study the statistics of the primordial power spectrum in models where massless gauge vectors are coupled to the inflaton, paying special attention to observational implications of having fundamental or effective horizons embedded in a…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-07 Mikjel Thorsrud , Federico R. Urban , David F. Mota

We propose a simple analytic fit for the power spectrum of scalar (curvature) perturbations during inflation, in order to describe slow roll of inflaton and formation of primordial black holes in the early universe, in the framework of…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-24 Daniel Frolovsky , Sergei V. Ketov

We study the impact of the use of the power series expression for the primordial tensor spectrum on parameter estimation from future direct detection gravitational wave experiments. The spectrum approximated by the power series expansion…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-19 Sachiko Kuroyanagi , Tomo Takahashi

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

The slow-roll inflation for a single scalar field that couples to the Gauss-Bonnet (GB) term represents an important higher-order curvature correction inspired by string theory. With the arrival of the era of precision cosmology, it is…

General Relativity and Quantum Cosmology · Physics 2018-05-09 Qiang Wu , Tao Zhu , Anzhong Wang

We consider the presence of oscillations in the primordial bispectrum, inspired by three different cosmological models; features in the primordial potential, resonant type non-Gaussianities and deviation from the standard Bunch Davies…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-03 P. Daniel Meerburg

The evolution of high order correlation functions of a test scalar field in arbitrary inflationary backgrounds is computed. Whenever possible, exact results are derived from quantum field theory calculations. Taking advantage of the fact…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-18 Francis Bernardeau

We study slow-roll inflation and the generation of primordial fluctuations in $F(T)$ gravity's rainbow. We obtain the second order action for scalar and tensor perturbations and then calculate the primordial power spectrum for them. Thus,…

General Relativity and Quantum Cosmology · Physics 2022-02-18 Yoelsy Leyva , Carlos Leiva , Giovanni Otalora , Joel Saavedra

The primordial bispectrum has been considered in the past decade as a powerful probe of the physical processes taking place in the early Universe. Within the inflationary paradigm, the properties of the bispectrum are one of the keys that…

General Relativity and Quantum Cosmology · Physics 2015-03-09 Gabriel Leon , Daniel Sudarsky
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