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We investigate the weak lensing corrections to the CMB polarization anisotropies. We concentrate on the effect of rotation and show that the rotation of polarisation is a true physical effect which has to be taken into account at second…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-25 Enea Di Dio , Ruth Durrer , Giuseppe Fanizza , Giovanni Marozzi

With the new generation of instruments for Cosmic Microwave Background (CMB) observations aiming at an accuracy level of a few percent in the measurement of the angular power spectrum of the anisotropies, the study of the contributions due…

Astrophysics · Physics 2007-05-23 N. Aghanim , S. Prunet , 0. Forni , F. R. Bouchet

We study CMB in the nonstandard background cosmology recently investigated. Using the previously calculated first order metric perturbations we discuss the Sachs-Wolfe and the integrated Sachs-Wolfe effects. We show how small-multipole CMB…

General Physics · Physics 2019-08-06 Gunter Scharf

This paper studies the problem of testing whether a function is monotone from a nonparametric Bayesian perspective. Two new families of tests are constructed. The first uses constrained smoothing splines, together with a hierarchical…

Methodology · Statistics 2014-06-03 James G. Scott , Thomas S. Shively , Stephen G. Walker

If the initial quantum state of the primordial perturbations broke rotational invariance, that would be seen as a statistical anisotropy in the angular correlations of the cosmic microwave background radiation (CMBR) temperature…

High Energy Physics - Theory · Physics 2016-12-02 Amjad Ashoorioon , Roberto Casadio , Tomi Koivisto

We address the issue of quantifying the non-Gaussian character of a bosonic quantum state and introduce a non-Gaussianity measure based on the Hilbert-Schmidt distance between the state under examination and a reference Gaussian state. We…

Quantum Physics · Physics 2009-11-13 Marco G. Genoni , Matteo G. A. Paris , Konrad Banaszek

We study the effect of primordial isocurvature perturbations on non-Gaussian properties of CMB temperature anisotropies. We consider generic forms of the non-linearity of isocurvature perturbations which can be applied to a wide range of…

A description of CMB temperature fluctuations beyond the power spectrum is important for verifying models of structure formation, especially in view of forthcoming high-resolution observations. We argue that higher-order statistics of…

Astrophysics · Physics 2007-05-23 S. Winitzki , J. H. P. Wu

In the context of the present and future Cosmic Microwave Background (CMB) experiments, going beyond the information provided by the power spectrum has become necessary in order to tightly constrain the cosmological model. The non-Gaussian…

Astrophysics · Physics 2008-11-26 N. Aghanim , M. Kunz , P. G. Castro , O. Forni

The observed hemispherical asymmetry in CMB map can be explained by modulation from a long wavelength super horizon mode which non-linearly couples to the CMB modes. We address the criticism in [1] about the role of non-Gaussianities in…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 Mohammad Hossein Namjoo , Ali Akbar Abolhasani , Shant Baghram , Hassan Firouzjahi

Cosmic microwave background radiation can supply us some most significant parts of the information on the universe. Some researchers believe that The gravitational system cannot be decribed by the standard statistical mechanics. In this…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-03 Yang Liu

Non-linear CMB temperature anisotropies up to the third-order on large scales are calculated. On large scales and in the Sachs-Wolfe limit, we give the explicit expression for the observed temperature anisotropy in terms of the primordial…

Cosmology and Nongalactic Astrophysics · Physics 2010-12-13 Xian Gao

We generate simulations of the CMB temperature field as observed by the WMAP satellite, taking into account the detailed shape of the asymmetric beams and scanning strategy of the experiment, and use these to re-estimate the WMAP beam…

Cosmology and Nongalactic Astrophysics · Physics 2012-02-02 Ingunn Kathrine Wehus , Lotty Ackerman , H. K. Eriksen , Nicolaas E. Groeneboom

We give an introduction to Gaussian states and operations. A discussion of the entanglement properties of bipartite Gaussian states in terms of its covariance matrix follows. It is explained how entanglement can be witnessed using feasible…

Quantum Physics · Physics 2007-05-23 Janet Anders

We investigate new shapes of local primordial non-Gaussianities in the CMB. Allowing for a primordial isocurvature mode along with the main adiabatic one, the angular bispectrum is in general a superposition of six distinct shapes: the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 David Langlois , Bartjan van Tent

One of the main goal of large-scale structure surveys is to test the consistency of General Relativity at cosmological scales. In the $\Lambda$CDM model of cosmology, the relations between the fields describing the geometry and the content…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-02 Daniel Sobral-Blanco , Camille Bonvin

Gravitational waves from inflation induce polarization patterns in the cosmic microwave background (CMB). It is known that there are only two types of non-Gaussianities of the gravitaional waves in the most general scalar field theories…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-01 Hiroaki W. H. Tahara , Jun'ichi Yokoyama

We evaluate the angular bispectrum of the CMB temperature anisotropy at large angular scale due to a stochastic background of primordial magnetic fields. The shape of non-Gaussianity depends on the spectral index of the magnetic field power…

Cosmology and Nongalactic Astrophysics · Physics 2009-10-02 Chiara Caprini , Fabio Finelli , Daniela Paoletti , Antonio Riotto

We study Quantum Gravity effects on the density of states in statistical mechanics and its implications for the critical temperature of a Bose Einstein Condensate and fraction of bosons in its ground state. We also study the effects of…

General Relativity and Quantum Cosmology · Physics 2021-08-04 Saurya Das , Mitja Fridman

We study the possible contribution of a stochastic gravitational wave background to the anisotropy of the cosmic microwave background (CMB) in cold and mixed dark matter (CDM and MDM) models. We test this contribution against recent…

Astrophysics · Physics 2009-10-31 A. Melchiorri , M. V. Sazhin , V. V. Shulga , N. Vittorio
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