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Related papers: Testing for Features in the Primordial Power Spect…

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The large-scale maximum at k~0.05 identified in the power-spectrum of galaxy fluctuations provides a co-moving scale for measuring cosmological curvature. In shallow 3D surveys the peak is broad, but appears to be well resolved in 1D, at…

Astrophysics · Physics 2007-05-23 Tom Broadhurst , Andrew H. Jaffe

The effect of the length of inflation on the power spectra of scalar and tensor perturbations is estimated using the power-law inflation model with a scale factor of a(t) = t^q. Considering various pre-inflation models with…

Astrophysics · Physics 2015-06-24 Shiro Hirai , Tomoyuki Takami

We study the growth of linear perturbations induced by a generic causal scaling source as a function of the cosmological parameters $h$, $\Omega^m_0$ and $\Omega^\Lambda_0$. We show that for wavenumbers $k \gsim 0.01 h/Mpc$ the spectrum of…

Astrophysics · Physics 2009-10-31 P. P. Avelino , J. P. M. de Carvalho

We explore the relationship between features in the Planck 2015 temperature and polarization data, shifts in the cosmological parameters, and features from inflation. Residuals in the temperature data at low multipole $\ell$, which are…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-18 Georges Obied , Cora Dvorkin , Chen Heinrich , Wayne Hu , V Miranda

We present constraints on the presence of isocurvature modes from the temperature and polarization CMB spectrum data from the WMAP satellite alone, and in combination with other datasets including SDSS galaxy survey and SNLS supernovae. We…

Astrophysics · Physics 2009-11-11 Rachel Bean , Joanna Dunkley , Elena Pierpaoli

We probe the scale dependence of the primordial spectrum in the light of the three-year WMAP (WMAP3) alone and WMAP3 in combination with the other cosmological observations such as galaxy clustering and Type Ia Supernova (SNIa). We pay…

Astrophysics · Physics 2010-10-27 Bo Feng , Jun-Qing Xia , Jun'ichi Yokoyama

We explore a broad class of three-parameter inflationary models, called the $\Lambda$-inflation, and its observational predictions: high abundance of cosmic gravitational waves consistent with the Harrison-Zel'dovich spectrum of primordial…

Astrophysics · Physics 2016-12-28 V. N. Lukash , E. V. Mikheeva

Scalar perturbations during inflation can be substantially amplified by tiny features in the inflaton potential. A bump-like feature behaves like a local speed-breaker and lowers the speed of the scalar field, thereby locally enhancing the…

General Relativity and Quantum Cosmology · Physics 2020-04-15 Swagat S. Mishra , Varun Sahni

We review the relevant 10+ parameters associated with inflation and matter content; the relation between LSS and primary and secondary CMB anisotropy probes; COBE constraints on energy injection; current anisotropy band-powers which…

Astrophysics · Physics 2009-10-30 J. Richard Bond , Andrew H. Jaffe

We develop methods to calculate the curvature power spectrum in models where features in the inflaton potential nonlinearly excite modes and generate high frequency features in the spectrum. The first nontrivial effect of excitations…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-18 V Miranda , Wayne Hu , Chen He , Hayato Motohashi

The improved data on the cosmic microwave background (CMB) anisotropy allow a better determination of the adiabaticity of the primordial perturbation. Interestingly, we find that recent CMB data seem to favor a contribution of a primordial…

Astrophysics · Physics 2008-11-26 Reijo Keskitalo , Hannu Kurki-Suonio , Vesa Muhonen , Jussi Valiviita

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

In this paper we break the scale invariance of the primordial power spectrum of curvature perturbations of inflation. Introducing a singular behaviour due to spontaneous symmetry breaking in the inflaton potential, we obtain fully analytic…

Astrophysics · Physics 2009-11-11 Jinn-Ouk Gong

The effect of pre-inflation physics on the power spectrum of scalar perturbations is estimated and there is a possibility that the pre-inflation physics explains the Wilkinson Microwave Anisotropy Probe data if the length of inflation is…

Astrophysics · Physics 2007-05-23 Shiro Hirai

We investigate the primordial power spectra for general kinetic inflation models that support a period of kinetic dominance in the case of curved universes. We present derivations of the Mukhanov-Sasaki equations with a nonstandard scalar…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-28 Zakhar Shumaylov , Will Handley

In models of inflation obtained from string compactification, moduli vacuum misalignment leads to an epoch in the post-inflationary history of the universe when the energy density is dominated by cold moduli particles. This effect leads to…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-04 Sukannya Bhattacharya , Koushik Dutta , Mayukh R. Gangopadhyay , Anshuman Maharana

We investigate the two-stage inflation regime in the theory of hybrid cosmological $\alpha$-attractors. The spectrum of inflationary perturbations is compatible with the latest Planck/BICEP/Keck results, thanks to the attractor properties…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-11 Matteo Braglia , Andrei Linde , Renata Kallosh , Fabio Finelli

We explore the three-point amplitude of curvature perturbations in scenarios suggested by high-scale supersymmetry breaking in String Theory, where the inflaton is forced to climb a steep exponential potential. We can do it at the price of…

High Energy Physics - Theory · Physics 2025-10-24 M. Meo , A. Sagnotti

In cosmological scenarios with thermal inflation, extra eras of moduli matter domination, thermal inflation and flaton matter domination exist between primordial inflation and the radiation domination of Big Bang nucleosynthesis. During…

Cosmology and Nongalactic Astrophysics · Physics 2017-02-06 Sungwook E. Hong , Hyung-Joo Lee , Young Jae Lee , Ewan D. Stewart , Heeseung Zoe

We investigate the presence of primordial oscillatory features in measurements of CMB anisotropies through a systematic comparison of phenomenological templates. Building upon previous searches for primordial features using Planck data, we…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-29 Antonio Raffaelli , Mario Ballardini , Nicola Barbieri
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