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Related papers: Tensor Anisotropies in an Open Universe

200 papers

An overview of some new results in open inflation over the past year, including the calculation of gravity wave contributions to the Cosmic Microwave Background. Proceedings for COSMO-97, held in Ambleside, U.K., hence very short due to…

Astrophysics · Physics 2016-10-26 J. D. Cohn

We solve the wave equation for the electromagnetic field tensors associated with the CMBR photons in a universe with scalar metric perturbations. We show that the coupling of the electromagnetic fields with the curvature associated with the…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Subhendra Mohanty , A. R. Prasanna

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

In almost all structure formation models, primordial perturbations are created within a homogeneous and isotropic universe, like the one we observe. Because their ensemble averages inherit the symmetries of the spacetime in which they are…

Astrophysics · Physics 2009-06-23 C. Armendariz-Picon

We assess the relative contribution to the COBE - measured microwave anisotropy arising both from relic gravity waves as well as primordial density perturbations originating during inflation. We show that the gravity wave contribution to…

High Energy Physics - Phenomenology · Physics 2007-05-23 Varun Sahni , Tarun Souradeep

We study the induced primordial gravitational waves (GW) coming from the effect of scalar perturbation on the tensor perturbation at the second order of cosmological perturbation theory. We use the evolution of the standard model degrees of…

High Energy Physics - Phenomenology · Physics 2020-02-19 Fazlollah Hajkarim , Jürgen Schaffner-Bielich

We compute the full bispectra, namely both auto- and cross- bispectra, of primordial curvature and tensor perturbations in the most general single-field inflation model whose scalar and gravitational equations of motion are of second order.…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-20 Xian Gao , Tsutomu Kobayashi , Maresuke Shiraishi , Masahide Yamaguchi , Jun'ichi Yokoyama , Shuichiro Yokoyama

The existence of large-scale anisotropy can not be ruled out by the cosmic microwave background (CMB) radiation. Over the years, several models have been proposed in the context of anisotropic inflation to account for CMB's cold spot and…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-15 Sourav Pal , Debaprasad Maity , Tuan Q. Do

We study the tensorial modes of the two-fluid model, where one of this fluids has an equation of state $p = - \rho/3$ (variable cosmological constant, cosmic string fluid, texture) or $p = - \rho$ (cosmological constant), while the other…

General Relativity and Quantum Cosmology · Physics 2007-05-23 J. C. Fabris , S. V. B. Goncalves

We make a detailed calculation of the amplitude of isocurvature perturbations arising from inflationary models in which the cold dark matter is represented by a scalar field which acquires perturbations during inflation. We use this to…

Astrophysics · Physics 2009-10-31 Andrew R Liddle , Anupam Mazumdar

We investigate the breaking of global statistical isotropy caused by a dark energy component with an energy-momentum tensor which has point symmetry, that could represent a cubic or hexagonal crystalline lattice. In such models Gaussian,…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-28 Richard Battye , Adam Moss

The Cosmic Microwave Background (CMB) anisotropy constrains the geometry of the Universe because the positions of the acoustic peaks of the angular power spectrum depend strongly on the curvature of underlying three-dimensional space. In…

Astrophysics · Physics 2009-11-13 J. Dunkley , M. Bucher , P. G. Ferreira , K. Moodley , C. Skordis

The inflationary scenario, which states that the early universe underwent a brief but dramatic period of accelerated spatial expansion, has become the current paradigm of early universe cosmology. Although inflationary cosmology has its…

General Relativity and Quantum Cosmology · Physics 2024-06-04 Eric Ling , Annachiara Piubello

We argue that the observed large-scale cosmic microwave anomalies, discovered by WMAP and confirmed by the Planck satellite, are most naturally explained in the context of a marginally-open universe. Particular focus is placed on the dipole…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-05 Andrew R Liddle , Marina Cortês

Cosmological solitons are widely predicted by scenarios of the early Universe. In this work, we investigate the isotropic background and anisotropies of gravitational waves (GWs) induced by soliton isocurvature perturbations, especially…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-04 Di Luo , Yan-Heng Yu , Jun-Peng Li , Sai Wang

We discuss effects of cosmological moduli fields on the cosmic microwave background (CMB). If a modulus field \phi once dominates the universe, the CMB we observe today is from the decay of \phi and its anisotropy is affected by the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Takeo Moroi , Tomo Takahashi

The production of a stochastic background of gravitational waves is a fundamental prediction of any cosmological inflationary model. The features of such a signal encode unique information about the physics of the Early Universe and beyond,…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-05 Maria Chiara Guzzetti , Nicola Bartolo , Michele Liguori , Sabino Matarrese

Weak lensing distortion of the background cosmic microwave background (CMB) temperature and polarization patterns by the foreground density fluctuations is well studied in the literature. We discuss the gravitational lensing modification to…

Astrophysics · Physics 2009-11-11 Chao Li , Asantha Cooray

We give a brief review of the physics of acoustic oscillations in Cosmic Microwave Background (CMB) anisotropies. As an example of the impact of their detection in cosmology, we show how the present data on CMB angular power spectrum on…

Astrophysics · Physics 2015-06-24 C. Baccigalupi , A. Balbi , S. Matarrese , F. Perrotta , N. Vittorio

In this article we review the theory of cosmological inflation with a particular focus on the beautiful connection it provides between the physics of the very small and observations of the very large. We explain how quantum mechanical…

Astrophysics · Physics 2010-04-30 Daniel Baumann , Hiranya V. Peiris