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Related papers: Primordial power spectrum versus extension paramet…

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We constrain several models of the early Universe that predict a statistical anisotropy of the cosmic microwave background (CMB) sky. We make use of WMAP9 maps deconvolved with beam asymmetries. As compared to previous releases of WMAP…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-03 Sabir Ramazanov , Grigory Rubtsov

We study features in the bispectrum of the primordial curvature perturbation correlated with the reconstructed primordial power spectrum from the observed cosmic microwave background temperature data. We first show how the bispectrum can be…

Cosmology and Nongalactic Astrophysics · Physics 2017-12-25 Stephen Appleby , Jinn-Ouk Gong , Dhiraj Kumar Hazra , Arman Shafieloo , Spyros Sypsas

The vacuum inflation with a boundary condition specified at a short-distance scale in a generally primeval non-flat Universe, and implications of the correspondingly modified primordial power spectrum via the WMAP data are investigated. We…

Astrophysics · Physics 2009-09-28 Jie Ren , Hong-Guang Zhang , Xin-He Meng

Understanding the universe in its pristine epoch is crucial in order to obtain a concise comprehension of the late-time universe. Although current data in cosmology are compatible with Gaussian primordial perturbations whose power spectrum…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-15 Thiago Mergulhão , Florian Beutler , John A. Peacock

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

We investigate how well galaxy cluster number counts can constrain the primordial power spectrum. Measurements of the primary anisotropies in the cosmic microwave background (CMB) may be limited, by the presence of foregrounds from…

Astrophysics · Physics 2015-03-13 Teeraparb Chantavat , Christopher Gordon , Joseph Silk

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

The model of holographic dark energy (HDE) with massive neutrinos and/or dark radiation is investigated in detail. The background and perturbation evolutions in the HDE model are calculated. We employ the PPF approach to overcome the…

Cosmology and Nongalactic Astrophysics · Physics 2015-04-24 Jing-Fei Zhang , Ming-Ming Zhao , Yun-He Li , Xin Zhang

Constraints on the main cosmological parameters using CMB or large scale structure data are usually based on power-law assumption of the primordial power spectrum (PPS). However, in the absence of a preferred model for the early universe,…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-14 Dhiraj Kumar Hazra , Arman Shafieloo , Tarun Souradeep

We constrain the growth index $\gamma$ by performing a full-shape analysis of the power spectrum multipoles measured from the BOSS DR12 data. We adopt a theoretical model based on the Effective Field theory of the Large Scale Structure…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-13 Chiara Moretti , Maria Tsedrik , Pedro Carrilho , Alkistis Pourtsidou

CMB observations provide a precise measurement of the primordial power spectrum on large scales, corresponding to wavenumbers $10^{-3}$ Mpc$^{-1}$ < k < 0.1 Mpc$^{-1}$, [1-8]. Luminous red galaxies and galaxy clusters probe the matter power…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-24 Razieh Emami , George Smoot

We compute primordial light-element abundances for cases with fine structure constant alpha different from the present value, including many sources of alpha dependence neglected in previous calculations. Specifically, we consider…

Astrophysics · Physics 2008-11-26 Kenneth M. Nollett , Robert E. Lopez

By using most of the present CMB and LSS measurements and the BBN constraints on the primordial helium abundance, Y_p, we set bounds on the radiation content of the Universe and neutrino properties. We consider lepton asymmetric…

Astrophysics · Physics 2010-02-26 Lucia Aurelia Popa , Ana Vasile

Primordial oscillatory features in the power spectrum of curvature perturbations are sensitive probes of the dynamics of the early Universe and can provide insights beyond the standard inflationary scenario. While these features have been…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-09 Mario Ballardini , Nicola Barbieri

While the simplest inflationary models predict a power-law form of the primordial power spectrum (PPS), various UV complete scenarios predict features on top of the standard power law that leave characteristic imprints in the late-time…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-26 Rodrigo Calderon , Théo Simon , Arman Shafieloo , Dhiraj Kumar Hazra

Reconstructing the shape of the primordial power spectrum in a model independent way from cosmological data is a useful consistency check on what is usually assumed regarding early universe physics. It is also our primary window to unknown…

Astrophysics · Physics 2008-11-26 Pia Mukherjee , Yun Wang

We present a minimally-parametric reconstruction of the primordial power spectrum using the most recent cosmic microwave background and large scale structure data sets. Our goal is to constrain the shape of the power spectrum while…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-06 Hiranya V. Peiris , Licia Verde

The South Pole Telescope (SPT), Atacama Cosmology Telescope (ACT), and Wilkinson Microwave Anisotropy Probe (WMAP) have each reported measurements of the cosmic microwave background's (CMB) angular power spectrum which favor the existence…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Dan Hooper , Farinaldo S. Queiroz , Nickolay Y. Gnedin

Combining measurements of the galaxy power spectrum and the cosmic microwave background (CMB) is a powerful means of constraining the summed mass of neutrino species sum(m_nu), but is subject to systematic uncertainties due to non-linear…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Molly E. C. Swanson , Will J. Percival , Ofer Lahav

One of the characteristics of the "Matter Bounce" scenario, an alternative to cosmological inflation for producing a scale-invariant spectrum of primordial adiabatic fluctuations on large scales, is a break in the power spectrum at a…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-18 Hong Li , Jun-Qing Xia , Robert Brandenberger , Xinmin Zhang
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