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We report the first constraints on the properties of weakly interacting low-mass dark matter (DM) particles using asteroseismology. The additional energy transport mechanism due to accumulated asymmetric DM particles modifies the central…

Solar and Stellar Astrophysics · Physics 2013-02-20 Jordi Casanellas , Ilídio Lopes

Magnetic fields appear to be a generic feature of the early universe and are a natural source of secondary CMB non-Gaussianity. In recent years the statistical nature of the stresses of a primordial magnetic field has been well studied. In…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Iain A. Brown

In inflationary models with minimal amount of gravity waves, the primordial power spectrum of density fluctuations, $A_S^2(k)$, together with the basic cosmological parameters, completely specify the predictions for the cosmic microwave…

Astrophysics · Physics 2009-10-31 Yun Wang , David N. Spergel , Michael A. Strauss

The presence of additional particles during inflation leads to non-Gaussianity in late-time correlators of primordial curvature perturbations. The shape and amplitude of this signal depend on the mass and spin of the extra particles.…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-16 Azadeh Moradinezhad Dizgah , Cora Dvorkin

We observationally examine cosmological models based on primordial power spectra with quantized wavevectors. Introducing a linearly quantized power spectrum with $k_0=3.225\times10^{-4}\mathrm{Mpc}^{-1}$ and spacing $\Delta k = 2.257 \times…

Cosmology and Nongalactic Astrophysics · Physics 2022-05-18 D. J. Bartlett , W. J. Handley , A. N. Lasenby

We study the two-point correlation function of density perturbations in a spherically symmetric void universe model which does not employ the Copernican principle. First we solve perturbation equations in the inhomogeneous universe model…

Cosmology and Nongalactic Astrophysics · Physics 2013-12-25 Ryusuke Nishikawa , Chul-Moon Yoo , Ken-ichi Nakao

One way of recovering information about the initial conditions of the Universe is by measuring features of the cosmological density field which are preserved during gravitational evolution and galaxy formation. In this paper we study the…

Astrophysics · Physics 2016-08-30 Rupert A. C. Croft , Enrique Gaztanaga

In order to quantify the error budget in the measured probability distribution functions of cell densities, the two-point statistics of cosmic densities in concentric spheres is investigated. Bias functions are introduced as the ratio of…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-08 Sandrine Codis , Francis Bernardeau , Christophe Pichon

The precision of the cosmological data allows us to accurately approximate the predictions for cosmological observables by Taylor expanding up to a low order the dependence on the cosmological parameters around a reference cosmology. By…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-17 Thomas Colas , Guido D'Amico , Leonardo Senatore , Pierre Zhang , Florian Beutler

The latest analysis of the cosmic microwave background by the Planck team finds more smoothing of the acoustic peaks in the temperature power spectrum than predicted by $\Lambda$CDM. Here we investigate whether this additional smoothing can…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-18 Guillem Domènech , Marc Kamionkowski

We estimate the maximum allowed amplitude for the power spectrum of the primordial curvature perturbations, ${\cal P_R}(k)$, on all scales from the absence of any detection signals of sub-solar mass black holes. In particular we analyze the…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-13 Ioannis Dalianis

Sudden violations of the slow-roll regime during inflation, a natural prediction of many UV-complete inflationary models, give rise to sharp features in the primordial power spectrum. At large scales, these features provide a unique window…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-05 Clément Stahl , Denis Werth , Vivian Poulin

We probe the statistical nature of the primordial density field by measuring correlations between the power in adjacent Fourier modes. For certain types of non-Gaussian field, these k-space correlations would be expected to be more extended…

Astrophysics · Physics 2016-06-08 A. J. Stirling , J. A. Peacock

The investigation of distant galaxy formation and evolution is a powerful tool to constrain dark matter scenarios, supporting and in some cases surpassing other astrophysical and experimental probes. The recent completion of the Hubble…

Cosmology and Nongalactic Astrophysics · Physics 2019-04-01 Marco Castellano , Nicola Menci , Andrea Grazian , Alexander Merle , Norma G. Sanchez , Aurel Schneider , Maximilian Totzauer

One of the main problems of observational cosmology is to determine the range in which a reliable measurement of galaxy correlations is possible. This corresponds to determine the shape of the correlation function, its possible evolution…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-18 Francesco Sylos Labini , Daniil Tekhanovich , Yurij V. Baryshev

We revisit the problem of constraining steps in the inflationary potential with cosmological data. We argue that a step in the inflationary potential produces qualitatively similar oscillations in the primordial power spectrum,…

Astrophysics · Physics 2008-11-26 Jan Hamann , Laura Covi , Alessandro Melchiorri , Anze Slosar

We discuss the issue of how precisely we can measure the primordial power spectrum by using future observations of 21 cm fluctuations and cosmic microwave background (CMB). For this purpose, we investigate projected constraints on the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Kazunori Kohri , Yoshihiko Oyama , Toyokazu Sekiguchi , Tomo Takahashi

As a simple model for unknown Planck scale physics, we assume that the quantum modes responsible for producing primordial curvature perturbations during inflation are placed in their instantaneous adiabatic vacuum when their proper momentum…

High Energy Physics - Theory · Physics 2008-11-26 J. C. Niemeyer , R. Parentani , D. Campo

We study the power spectrum of the mass density perturbations in an inflation scenario that includes thermal dissipation. We show that the condition on which the thermal fluctuations dominate the primordial density perturbations can easily…

Astrophysics · Physics 2009-10-31 Wolung Lee , Li-Zhi Fang

We present the first attempt to use a combination of CMB, LIGO, and PPTA data to constrain both the tilt and the running of primordial tensor power spectrum through constraints on the gravitational wave energy density generated in the early…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 P. Daniel Meerburg , Renée Hložek , Boryana Hadzhiyska , Joel Meyers
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