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Related papers: Cosmic Strings as the Source of Small-Scale Microw…

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We study the effect of free streaming in a universe with cosmic strings with time-varying tension as well as with constant tension. Although current cosmological observations suggest that fluctuation seeded by cosmic strings cannot be the…

High Energy Physics - Phenomenology · Physics 2009-11-11 Tomo Takahashi , Masahide Yamaguchi

The advent of high resolution cosmic microwave background (CMB) experiments now allows studies on the temperature fluctuations at scales corresponding to few arcminutes and below. Though the reported excess power at $\ell \sim 2000 - 6000$…

Astrophysics · Physics 2009-11-07 Asantha Cooray , Alessandro Melchiorri

Non-commutative inflation is a modification of standard general relativity inflation which takes into account some effects of the space-time uncertainty principle motivated by ideas from string theory. The corrections to the primordial…

Astrophysics · Physics 2009-03-31 Shinji Tsujikawa , Roy Maartens , Robert Brandenberger

The anisotropies in the cosmic microwave background (CMB) provide our best laboratory for testing models of the formation and evolution of large-scale structure. The rich features in the cosmic microwave background anisotropy spectrum, in…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Zhen Pan , Lloyd Knox , Martin White

${\rm B - L}$ cosmic strings form in a wide class of theories beyond the Standard Model which contain a ${\rm U}(1)_{{\rm B - L}}$ gauge symmetry. They can form at the end of hybrid inflation and explain, together with inflation, the Cosmic…

High Energy Physics - Phenomenology · Physics 2007-05-23 R. Jeannerot

The lowest multipole moments of the cosmic microwave background (CMB) are smaller than expected for a scale-invariant power spectrum. One possible explanation is a cutoff in the primordial power spectrum below a comoving scale of $k_c…

Astrophysics · Physics 2009-11-10 Michael Kesden , Marc Kamionkowski , Asantha Cooray

We propose a multi-scale edge-detection algorithm to search for the Gott-Kaiser-Stebbins imprints of a cosmic string (CS) network on the Cosmic Microwave Background (CMB) anisotropies. Curvelet decomposition and extended Canny algorithm are…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-12 A. Vafaei Sadr , S. M. S. Movahed , M. Farhang , C. Ringeval , F. R. Bouchet

The Cosmic Microwave Background (CMB), which permeates the entire Universe, is the radiation left over from just 380,000 years after the Big Bang. On very large scales, the CMB radiation field is smooth and isotropic, but the existence of…

The mean spectrum and burst statistics of gravitational waves produced by a cosmological population of cosmic string loops are estimated using analytic approximations, calibrated with earlier simulations. Formulas are derived showing the…

Astrophysics · Physics 2009-11-11 Craig J. Hogan

The weak lensing effect on the cosmic microwave background (CMB) induces distortions in spatial pattern of CMB anisotropies, and statistical properties of CMB anisotropies become a weakly non-Gaussian field. We first summarize the weak…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-17 Toshiya Namikawa

The power spectrum of fluctuations in the cosmic microwave background (CMB) depends on most of the key cosmological parameters. Accurate future measurements of this power spectrum might therefore allow us to determine h, Omega, Omega_b,…

Astrophysics · Physics 2007-05-23 Max Tegmark

We investigate the possibility that a heavy scalar field, whose mass exceeds the Hubble scale during inflation, could leave non-negligible signatures in the Cosmic Microwave Background (CMB) temperature anisotropy power spectrum through the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Ryo Saito , Masahiro Nakashima , Yu-ichi Takamizu , Jun'ichi Yokoyama

It is well known that processes of first order phase transitions may have occurred in the inflationary era. If one or more occurred well before the end of inflation, the nucleated bubbles are stretched to large scales and the primordial…

Astrophysics · Physics 2009-10-30 Carlo Baccigalupi

We use the publicly available code CMBFAST as modified by L. Pogosian and T. Vachaspati to simulate the effects of wiggly cosmic strings on the Cosmic Microwave Background (CMB). Using the modified CMBFAST code which takes into account…

Astrophysics · Physics 2011-05-10 N. Simatos , L. Perivolaropoulos

Thomson scattering of the Cosmic Microwave Background (CMB) on moving electrons in the outflows of Lyman Break Galaxies (LBGs) at redshifts 2-8 contributes to the small-scale CMB anisotropies. The net effect produced by each outflow depends…

Astrophysics · Physics 2009-11-11 Daniel Babich , Abraham Loeb

We compute the power spectra in the cosmic microwave background and cold dark matter (CDM) fluctuations seeded by strings, using the largest string simulations performed so far to evaluate the two-point functions of their stress energy…

Astrophysics · Physics 2009-10-30 Carlo Contaldi , Mark Hindmarsh , Joao Magueijo

It has been argued that the power spectrum of the anisotropies in the Cosmic Microwave Background (CMB) may be effectively degenerate, namely that the observable spectrum does not determine a unique set of cosmological parameters. We…

Astrophysics · Physics 2015-06-24 R. Benton Metcalf , Joseph Silk

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

The major contribution to the anisotropy of the temperature of the Cosmic Microwave Background (CMB) radiation is believed to come from the interaction of linear density perturbations with the radiation previous to the decoupling time.…

Astrophysics · Physics 2015-06-24 Enrique Martinez-Gonzalez

Fluctuations in the intensity and polarization of the cosmic microwave background (CMB) and the large-scale distribution of matter in the universe each contain clues about the nature of the earliest moments of time. The next generation of…