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Related papers: Cosmic String Power Spectrum, Bispectrum and Trisp…

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Nonlinear effects are crucial in order to compute the cosmological matter power spectrum to the accuracy required by future generation surveys. Here, a new approach is presented, in which the power spectrum, the bispectrum and higher order…

Astrophysics · Physics 2009-11-13 Massimo Pietroni

Measurement of the cosmic microwave background (CMB) bispectrum, or three-point correlation function, has now become one of the principle efforts in early-Universe cosmology. Here we show that there is a odd-parity component of the CMB…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-03 Marc Kamionkowski , Tarun Souradeep

Perturbations from inflation evolve into large scale structure of the late universe, and encode abundant cosmic structure formation physics. We allow freedom in the primordial power spectrum, rather than assuming a power law scale…

Cosmology and Nongalactic Astrophysics · Physics 2020-05-12 Guilherme Brando , Eric V. Linder

Brane inflation in superstring theory predicts that cosmic strings (but not domain walls or monopoles) are produced towards the end of the inflationary epoch. Here, we discuss the production, the spectrum and the evolution of such cosmic…

High Energy Physics - Theory · Physics 2009-11-10 Nicholas T. Jones , Horace Stoica , S. -H. Henry Tye

We use an iterative generalized least squares map-making algorithm, in conjunction with Monte Carlo techniques, to obtain estimates of the angular power spectrum from cosmic microwave background (CMB) maps. This is achieved by…

Astrophysics · Physics 2009-11-07 A. Balbi , G. de Gasperis , P. Natoli , N. Vittorio

Using the formalism developed in a previous paper we analyze the cosmological implications of our conclusions concerning the scaling behaviour of a network of cosmic strings, in particular the idea that once gravitational back-reaction…

High Energy Physics - Phenomenology · Physics 2010-01-06 Daren Austin , E. J. Copeland , T. W. B. Kibble

We derive general expressions for how the Alcock-Paczynski distortions affect the power spectrum and the bispectrum of cosmological fields. We compute explicit formulas for the mixing coefficients of bispectrum multipoles in the linear…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-09 Giorgi Khomeriki , Lado Samushia

Current data exclude cosmic strings as the primary source of primordial density fluctuations. However, in a wide class of inflationary models, strings can form at later stages of inflation and have potentially detectable observational…

Astrophysics · Physics 2009-11-10 Levon Pogosian , Mark Wyman , Ira Wasserman

In the inflationary scenarios suggested by string theory, the vacuum fluctuations of the electromagnetic field can be amplified by the time-evolution of the dilaton background, and can grow large enough to explain both the origin of the…

Astrophysics · Physics 2010-01-06 M. Gasperini , M. Giovannini , G. Veneziano

We compare the spectrum of the stochastic gravitational wave background produced in several models of cosmic strings with the common-spectrum process recently reported by NANOGrav. We discuss theoretical uncertainties in computing such a…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-19 Jose J. Blanco-Pillado , Ken D. Olum , Jeremy M. Wachter

We undertake a thorough search for signatures of sharp oscillatory features in the WMAP9 power spectrum and bispectrum as well as in the Planck power spectrum. For the first time, we carry out searches in both the power spectrum and…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-27 J. R. Fergusson , H. F. Gruetjen , E. P. S. Shellard , B. Wallisch

As wide-field surveys yield increasingly precise data, multiprobe analyses offer significant advantages. In this work, we use our previously developed framework for jointly analyzing cosmic microwave background (CMB) and large-scale…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-01 Alexander Reeves , Andrina Nicola , Alexandre Refregier

Different inflationary models predict oscillatory features in the primordial power spectrum. These can leave an imprint on both the cosmic microwave background (CMB) and the large-scale structure (LSS) of our Universe, that can be searched…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-15 Chenxiao Zeng , Ely D. Kovetz , Xuelei Chen , Yan Gong , Julian B. Muñoz , Marc Kamionkowski

In these lectures, I review the current status of cosmic strings and cosmic superstrings. I first discuss topological defects in the context of Grand Unified Theories, focusing in particular in cosmic strings arising as gauge theory…

High Energy Physics - Theory · Physics 2009-10-06 Mairi Sakellariadou

The nonlinear interaction between one graviton and two scalars is enhanced in specific inflationary models, potentially leading to distinguishable signatures in the bispectrum of the cosmic microwave background (CMB) anisotropies. We…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-15 Maresuke Shiraishi , Michele Liguori , James R. Fergusson

We propose a fast and efficient bispectrum statistic for Cosmic Microwave Background (CMB) temperature anisotropies to constrain the amplitude of the primordial non-Gaussian signal measured in terms of the non-linear coupling parameter…

Astrophysics · Physics 2009-11-11 P. Cabella , F. K. Hansen , M. Liguori , D. Marinucci , S. Matarrese , L. Moscardini , N. Vittorio

In this paper, we present the first comprehensive CMB data analysis of cosmological collider physics. New heavy particles during inflation can leave imprints in the primordial correlators which are observable in today's cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-06 Wuhyun Sohn , Dong-Gang Wang , James R. Fergusson , E. P. S. Shellard

We build an inflationary model based on Degenerate Higher Order Scalar Tensor (DHOST) theories in a de Sitter background. We determine the scale-dependent power spectrum of curvature perturbations in these theories and we show that such a…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-25 Andrei Lazanu

Towards the end of the brane inflationary epoch in the brane world, cosmic strings (but not texture, domain walls or monopoles) are copiously produced during brane collision. These cosmic strings are D$p$-branes with $(p-1)$ dimensions…

High Energy Physics - Theory · Physics 2009-11-07 Saswat Sarangi , S. -H. Henry Tye

We examine the effects of cosmic strings on structure formation and on the ionization history of the universe. While Gaussian perturbations from inflation are known to provide the dominant contribution to the large scale structure of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Benjamin Shlaer , Alexander Vilenkin , Abraham Loeb
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