English
Related papers

Related papers: Imprints of microcausality violation on the cosmic…

200 papers

Inflationary cosmology provides a natural mechanism for the generation of primordial perturbations which seed the formation of observed cosmic structure and lead to specific signals of anisotropy in the cosmic microwave background…

Astrophysics · Physics 2011-07-19 Salman Habib , Andreas Heinen , Katrin Heitmann , Gerard Jungman

We study the effects on cosmic microwave background (CMB) temperature and polarization anisotropies of spatial fluctuations of the fine-structure parameter between causally disconnected regions of the Universe at the time of recombination.…

Astrophysics · Physics 2014-10-13 Kris Sigurdson , Andriy Kurylov , Marc Kamionkowski

Quantum field theories on noncommutative spacetime have many different properties from those on commutative spacetime. In this paper, we study the microcausality of free scalar field on noncommutative spacetime. We expand the scalar field…

High Energy Physics - Theory · Physics 2007-07-30 Zheng Ze Ma

We develop an analytic method and approximations to compute the polarization induced in the cosmic microwave background radiation on a wide range of angular scales by anisotropic Thomson scattering in presence of adiabatic scalar…

Astrophysics · Physics 2009-10-28 Matias Zaldarriaga , Diego D. Harari

Following a new quantum cosmological model proposed by Dvali and Gomez, we quantitatively investigate possible modifications to the Hubble parameter and following corrections to the cosmic microwave background spectrum. In this model,…

General Relativity and Quantum Cosmology · Physics 2015-09-16 Roberto Casadio , Florian Kuhnel , Alessio Orlandi

Inflation creates both scalar (density) and tensor (gravity wave) metric perturbations. We find that the tensor mode contribution to the CMB anisotropy on large-angular scales can only exceed that of the scalar mode in models where the…

Astrophysics · Physics 2009-09-15 R. L. Davis , H. M. Hodges , G. F. Smoot , P. J. Steinhardt , M. S. Turner

We consider the consequences of an observed Cosmic Microwave Background (CMB) temperature anisotropy spectrum containing no secondary oscillations. While such a spectrum is generally considered to be a robust signature of active structure…

Astrophysics · Physics 2010-04-08 Alex Lewin , Andreas Albrecht

The analysis of anisotropies in the cosmic microwave background (CMB) has become an extremely valuable tool for cosmology. We even have hopes that planned CMB anisotropy experiments may revolutionize cosmology. Together with determinations…

Astrophysics · Physics 2011-04-15 Ruth Durrer

These lecture notes present the computation of the full system of Boltzmann equations describing the evolution of the photon, baryon and cold dark matter fluids up to second order in perturbation theory, as recently studied in (Bartolo,…

Astrophysics · Physics 2007-05-23 Nicola Bartolo , Sabino Matarrese , Antonio Riotto

See comments. We calculate analytically an effect of the thermal Comptonization on the cosmic microwave background (CMB) photons when they propagate through galaxy clusters. We estimate a deformation of the CMB spectrum due to multiple…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-26 Lev Titarchuk , Galina Lipunova

We evaluate the large scale polarization of the cosmic microwave background induced, via Thomson scattering prior to decoupling, by nearly scale-invariant spectra of scalar and tensor metric perturbations, such as those predicted by most…

Astrophysics · Physics 2016-08-30 Diego Harari , Matias Zaldarriaga

The anisotropies of the cosmic microwave background (CMB) are computed for the half-turn space E_2 which represents a compact flat model of the Universe, i.e. one with finite volume. This model is inhomogeneous in the sense that the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 R. Aurich , S. Lustig

Nonlinear gravitational effects of large-scale inhomogeneities on Cosmic Microwave Background (CMB) anisotropies are studied. based on the relativistic second-order theory of perturbations in nonzero-Lambda flat cosmological models, which…

Astrophysics · Physics 2009-11-11 Kenji Tomita

Various issues concerning the impact of inflationary models on parameter estimation from the cosmic microwave background are reviewed, with particular focus on the range of possible outcomes of inflationary models and on the amount which…

Astrophysics · Physics 2009-10-31 Andrew R Liddle

We develop a formalism for calculating cosmic microwave background (CMB) temperature and polarization anisotropies in cosmological models with Brans-Dicke gravity. We then modify publicly available Boltzmann codes to calculate numerically…

Astrophysics · Physics 2008-11-26 Xuelei Chen , Marc Kamionkowski

We examine the effects Lorentz violation on observations of cosmic microwave background radiation. In particular, we focus on changes in polarization caused by vacuum birefringence. We place stringent constraints on previously untested…

Astrophysics · Physics 2007-10-08 Matthew Mewes

We revisit the issue on signatures of pre-inflationary background anisotropy by considering the quantization of a massless and minimally coupled scalar field in an axially symmetric Kasner background, mimicking cosmological perturbations.…

General Relativity and Quantum Cosmology · Physics 2017-03-29 Hyeong-Chan Kim , Masato Minamitsuji

The cosmic microwave background (CMB) temperature anisotropies from primordial magnetic fields are studied. In addition to the known passive and the compensated mode we discuss an inflationary magnetic mode in the curvature perturbation,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Camille Bonvin , Chiara Caprini , Ruth Durrer

We study the cosmic microwave background (CMB) temperature fluctuations non-gaussianity due to the vector mode perturbations (Alfv\'en waves) supported by a stochastic cosmological magnetic field. We present detailed derivations of the…

Cosmology and Nongalactic Astrophysics · Physics 2012-10-01 Tina Kahniashvili , George Lavrelashvili

One of the major predictions of inflation is the existence of a stochastic background of cosmological gravitational waves (GW). These gravitational waves can induce significant temperature anisotropies in the Cosmic Microwave Background…

Astrophysics · Physics 2009-11-07 Alessandro Melchiorri , Carolina Odman