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The Multi-coupled Dark Energy (McDE) scenario has been recently proposed as a specific example of a cosmological model characterized by a non-standard physics of the dark sector of the universe that nevertheless gives an expansion history…

Cosmology and Nongalactic Astrophysics · Physics 2014-02-27 Arpine Piloyan , Valerio Marra , Marco Baldi , Luca Amendola

Using a Gibbs sampling algorithm for joint CMB estimation and component separation, we compute the large-scale CMB and foreground posteriors of the 3-yr WMAP temperature data. Our parametric data model includes the cosmological CMB signal…

Astrophysics · Physics 2010-11-11 H. K. Eriksen , C. Dickinson , J. B. Jewell , A. J. Banday , K. M. Gorski , C. R. Lawrence

The most general initial conditions of CMB anisotropies, compatible with the presence of pre-equality magnetic fields, are derived. When the plasma is composed by photons, baryons, electrons, CDM particles and neutrinos, the initial data of…

Astrophysics · Physics 2008-11-26 Massimo Giovannini , Kerstin E. Kunze

Working toward a model independent understanding of cosmic microwave background (CMB) anisotropies and their significance, we undertake a comprehensive and self-contained study of scalar perturbation theory. Initial conditions, evolution,…

Astrophysics · Physics 2009-09-25 Wayne Hu , Naoshi Sugiyama

The CMB angular temperature fluctuations observed by COBE and WMAP enable us to place a lower limit on the spectral distortions of the CMB at any angular scale. These distortions are connected with the simple fact, that the superposition of…

Astrophysics · Physics 2009-11-10 J. Chluba , R. A. Sunyaev

We present a cross-correlation analysis of the WMAP cosmic microwave background (CMB) temperature anisotropies and the SDSS galaxy density fluctuations. We find significant detections of the angular CMB-galaxy correlation for both the flux…

Astrophysics · Physics 2007-05-23 Pablo Fosalba , Enrique Gaztanaga , Francisco Castander

Abbreviated: We highlight the remarkable evolution in the CMB power spectrum over the past few years, and in the cosmological parameters for minimal inflation models derived from it. Grand unified spectra (GUS) show pre-WMAP optimal…

Astrophysics · Physics 2015-06-24 J. R. Bond , C. R. Contaldi , D. Pogosyan

If time-dependent disruptions from slow-roll occur during inflation, the correlation functions of the primordial curvature perturbation should have scale-dependent features, a case which is marginally supported from the cosmic microwave…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-04 Jinn-Ouk Gong , Gonzalo A. Palma , Spyros Sypsas

In the covariant cosmological perturbation theory, a 1+3 decomposition ensures that all variables in the frame-independent equations are covariant, gauge-invariant and have clear physical interpretations. We develop this formalism in the…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-18 Fengquan Wu , Li-e Qiang , Xin Wang , Xuelei Chen

Evidences for late-time acceleration of the Universe are provided by multiple probes, such as Type Ia supernovae, the cosmic microwave background (CMB) and large-scale structure (LSS). In this work, we focus on the integrated Sachs--Wolfe…

Cosmology and Nongalactic Astrophysics · Physics 2016-07-27 E. Moura Santos , F. C. Carvalho , M. Penna-Lima , C. P. Novaes , C. A. Wuensche

We review aspects of Cosmic Microwave Background (CMB) spectral distortions which do not appear to have been fully explored in the literature. In particular, implications of recent evidences of heating of the intergalactic medium (IGM) by…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-13 G. De Zotti , M. Negrello , G. Castex , A. Lapi , M. Bonato

We investigate early dark energy models in the context of the lensing anomaly by considering two different Cosmic Microwave Background (CMB) datasets: a complete Planck, and a second one primarily based on SPTPol and Planck temperature…

Cosmology and Nongalactic Astrophysics · Physics 2022-12-20 Balakrishna S. Haridasu , Hasti Khoraminezhad , Matteo Viel

The predicted present-day amplitude of matter fluctuations based on cosmic microwave background (CMB) anisotropy data has sometimes been found discrepant with more direct measurements of late-time structure. This has motivated many…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-14 Alex Laguë , Fiona McCarthy , Mathew Madhavacheril , J. Colin Hill , Frank J. Qu

Unexpected features have been observed in the cosmic microwave background (CMB) temperature on large scales. We revisit these CMB anomalies using new foreground-cleaned CMB temperature maps derived in a companion paper from WMAP and Planck…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-05 Laura Herold , Graeme E. Addison , Charles L. Bennett , Hayley C. Nofi , J. L. Weiland

The existence of dark radiation that is completely decoupled from the standard model in the early Universe leaves open the possibility of an associated dark radiation isocurvature mode. We show that the presence of dark radiation…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-12 Peter Adshead , Gilbert Holder , Pranjal Ralegankar

We examine Gaussian isocurvature hot dark matter (massive neutrino) models for large-scale structure in which the initial density perturbations are produced in the baryons with a power--law spectrum $P_B(k) = Ak^{n_B}$. We calculate the…

Astrophysics · Physics 2009-10-28 Andrew A. de Laix , Rober J. Scherrer

We compare the predictions of hybrid inflationary models that produce both adiabatic fluctuations and topological defects to first year WMAP results. We use a Markov Chain Monte Carlo method to constrain the contribution of cosmic strings…

Astrophysics · Physics 2007-05-23 Aurélien A. Fraisse

We study non-Gaussian properties of the isocurvature perturbations in the dark radiation, which consists of the active neutrinos and extra light species, if exist. We first derive expressions for the bispectra of primordial perturbations…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Etsuko Kawakami , Masahiro Kawasaki , Koichi Miyamoto , Kazunori Nakayama , Toyokazu Sekiguchi

Recent measurements by the {\it Planck} experiment of the power spectrum of temperature anisotropies in the cosmic microwave background radiation (CMB) reveal a deficit of power in low multipoles compared to the predictions from best-fit…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-19 Katelin Schutz , Evangelos I. Sfakianakis , David I. Kaiser

We use the WMAP 7 data to place constraints on oscillations supplementing an almost scale-invariant primordial power spectrum. Such oscillations are predicted by a variety of models, some of which amount to assuming there is some…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 P. Daniel Meerburg , Ralph Wijers , Jan Pieter van der Schaar
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