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The COBE satellite has discovered anisotropies in the cosmic microwave background (CMB) consistent with a scale invariant spectrum of density perturbations. As reviewed in this lecture, topological defect models of structure formation…

High Energy Physics - Phenomenology · Physics 2007-05-23 Robert H. Brandenberger

Anisotropies in the Cosmic Microwave Background (CMB) contain a wealth of information about the past history of the universe and the present values of cosmological parameters. I ouline some of the theoretical advances of the last few years.…

Astrophysics · Physics 2007-05-23 Scott Dodelson

Recent detections of cosmic microwave background (CMB) anisotropy at half-degree angular scales show considerable scatter in the reported amplitude even at similar angular resolution. We use Monte Carlo techniques to simulate the current…

Astrophysics · Physics 2007-05-23 A. Kogut , G. Hinshaw

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 use weighted mean and median statistics techniques to combine individual cosmic microwave background (CMB) anisotropy detections and determine binned, multipole-space, CMB anisotropy power spectra. The resultant power spectra are peaked.…

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 compare the anisotropies in the cosmic microwave background radiation measured by the COBE experiment to the predictions of cosmic strings. We use an analytic model for the $\Delta T/T$ power spectrum that is based on our previous…

High Energy Physics - Phenomenology · Physics 2009-10-22 David P. Bennett , Albert Stebbins , Francois R. Bouchet

We report on a measurement of the angular power spectrum of the anisotropy in the Cosmic Microwave Background. The anisotropy is measured in 23 different multipole bands from l=54 (~3 deg) to l=404 (~0.45 deg) and in 6 frequency bands from…

Astrophysics · Physics 2009-10-28 C. B. Netterfield , M. J. Devlin , N. Jarosik , L. Page , E. J. Wollack

I review recent progress towards a detailed understanding of the power spectrum of cosmic string perturbations induced on the Microwave Background (CMB). The use of a simple analytic model allows to include important effects that have not…

Astrophysics · Physics 2007-05-23 Leandros Perivolaropoulos

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

We present new cosmic microwave background (CMB) anisotropy results from the combined analysis of the three flights of the first Medium Scale Anisotropy Measurement (MSAM1). This balloon-borne bolometric instrument measured about 10 square…

Motivated by the morphological measures in assessing the geometrical and topological properties of a generic cosmological stochastic field, we propose an extension of the weighted morphological measures, specifically the $n$th conditional…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-19 Adeela Afzal , M. Alakhras , M. H. Jalali Kanafi , S. M. S. Movahed

We present a significant improvement over our previous calculations of the cosmic string contribution to cosmic microwave background (CMB) power spectra, with particular focus on sub-WMAP angular scales. These smaller scales are relevant…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Neil Bevis , Mark Hindmarsh , Martin Kunz , Jon Urrestilla

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

In this paper we consider the question of observational signatures of a false vacuum decay event in the early universe followed by a period of inflation; in particular, motivated by the string landscape, we consider decays in which the…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-26 James H. C. Scargill

These lecture notes form a primer on the theory of cosmic microwave background (CMB) anisotropy formation. With emphasis on conceptual aspects rather than technical issues, we examine the physical foundations of anisotropy evolution in…

Astrophysics · Physics 2015-06-24 Wayne Hu

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

We study diffusion damping of acoustic waves in the photon-baryon fluid due to cosmic strings, and calculate the induced $\mu$- and $y$-type spectral distortions of the cosmic microwave background. For cosmic strings with tension within…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-21 Hiroyuki Tashiro , Eray Sabancilar , Tanmay Vachaspati

In the first part of this work, I review the theoretical framework of cosmological perturbation theory necessary to understand the generation and evolution of cosmic microwave background (CMB) anisotropies. Using analytical and numerical…

Astrophysics · Physics 2009-09-29 Roberto Trotta

We report improved measurements of temperature anisotropies in the cosmic microwave background (CMB) radiation made with the Arcminute Cosmology Bolometer Array Receiver (ACBAR). In this paper, we use a new analysis technique and include…

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