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Recently, BICEP2 measurements of the cosmic microwave background (CMB) $B$-mode polarization has indicated the presence of primordial gravitational waves at degree angular scales, inferring the tensor-to-scalar ratio of $r=0.2$ and a…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-11 Seokcheon Lee , Guo-Chin Liu , Kin-Wang Ng

A procedure is suggested for calculating electro-excitation multipoles to order $1/M^{2}_{N}$ with only the operators required in the calculations to order $1/M_{N}$. It is also shown that calculations to order $1/M^{2}_{N}$ cannot account…

Nuclear Theory · Physics 2015-06-19 J. Grineviciute , Dean Halderson

Near lightcone correlators are dominated by operators with the lowest twist. We consider the contributions of such leading lowest twist multi-stress tensor operators to a heavy-heavy-light-light correlator in a CFT of any even…

High Energy Physics - Theory · Physics 2020-01-29 Robin Karlsson , Manuela Kulaxizi , Andrei Parnachev , Petar Tadić

The recently detected polarization of the cosmic microwave background (CMB) holds the potential for revealing the physics of inflation and gravitationally mapping the large-scale structure of the universe, if so called B-mode signals below…

Astrophysics · Physics 2011-05-12 Wayne Hu , Matthew M. Hedman , Matias Zaldarriaga

In this short article, we overview a concept of electronic toroidal multipoles, and their ordering with associated physical properties in non-magnetic and magnetic materials. The toroidal multipoles are introduced as microscopic electronic…

Materials Science · Physics 2024-09-12 Hiroaki Kusunose , Satoru Hayami

On large angular scales (greater than about 60 degrees), the two-point angular correlation function of the temperature of the cosmic microwave background (CMB), as measured (outside of the plane of the Galaxy) by the Wilkinson Microwave…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Devdeep Sarkar , Dragan Huterer , Craig J. Copi , Glenn D. Starkman , Dominik J. Schwarz

The estimation of cosmological parameters from cosmic microwave experiments has almost always been performed assuming gaussian data. In this paper the sensitivity of the parameter estimation to different assumptions on the probability…

Astrophysics · Physics 2009-11-07 Luca Amendola

The statistical properties of a map of the primary fluctuations in the cosmic microwave background (CMB) may be specified to high accuracy by a few thousand power spectra measurements, provided the fluctuations are gaussian, yet the number…

Astrophysics · Physics 2009-11-07 Sujata Gupta , Alan F. Heavens

We study constraints on time variation of the fine structure constant alpha from cosmic microwave background (CMB) taking into account simultaneous change in alpha and the electron mass m_e which might be implied in unification theories. We…

Astrophysics · Physics 2008-11-26 Kazuhide Ichikawa , Toru Kanzaki , Masahiro Kawasaki

The recent BICEP2 detection of degree scale CMB B-mode polarization, coupled with a deficit of observed power in large angle temperature anisotropy, suggest that the slow-roll parameter $\epsilon_H$, the fractional variation in the Hubble…

Cosmology and Nongalactic Astrophysics · Physics 2014-06-11 Wayne Hu

In nonlinear deterministic parameter estimation, the maximum likelihood estimator (MLE) is unable to attain the Cramer-Rao lower bound at low and medium signal-to-noise ratios (SNR) due the threshold and ambiguity phenomena. In order to…

Applications · Statistics 2015-06-19 Achraf Mallat , Sinan Gezici , Davide Dardari , Christophe Craeye , Luc Vandendorpe

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

Comparison of theobservedanisotropy with that predicted iadiabaticDM models suggest that much of thserved signal may be due to long wavelenh gravitational waves. In inflationary models this requires the generation of tensor fluctuations to…

High Energy Physics - Phenomenology · Physics 2007-05-23 Lawrence M. Krauss

We compute the coefficients $c_2(T,B)$ and $c_4(T,B)$ of the Taylor expansion for the pressure in powers of $\mu_B/T$ in the presence of a large magnetic field within perturbative QCD at finite temperature and baryon density up to two-loops…

High Energy Physics - Phenomenology · Physics 2026-01-14 Eduardo S. Fraga , Letícia F. Palhares , Tulio E. Restrepo

Assuming that the cosmological principle holds, Maartens, Ellis and Stoeger (MES) recently constructed a detailed scheme linking anisotropies in the cosmic background radiation (CMB) with anisotropies and inhomogeneities in the large scale…

Astrophysics · Physics 2008-12-01 William Stoeger , Marcelo Araujo , Tim Gebbie

We present the temperature and polarization angular power spectra of the cosmic microwave background (CMB) derived from the first 5 years of WMAP data. The 5-year temperature (TT) spectrum is cosmic variance limited up to multipole l=530,…

Tensor modes in the cosmic microwave background are one of the most robust signatures of inflation. We derive theoretical bounds on the tensor fraction, as a generalization of the well-known Lyth bound. Under reasonable assumptions, the new…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-27 Lotfi Boubekeur

Recent work has emphasised the importance of vector and tensor contributions to the large scale microwave anisotropy fluctuations produced by cosmic defects. In this paper we provide a general discussion of these contributions, and how…

Astrophysics · Physics 2008-11-26 Neil Turok , Ue-Li Pen , Uros Seljak

In the context of cosmic microwave background (CMB) data analysis, we compare the efficiency at large scale of two angular power spectrum algorithms, implementing, respectively, the quadratic maximum likelihood (QML) estimator and the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 Diego Molinari , Alessandro Gruppuso , Gianluca Polenta , Carlo Burigana , Adriano De Rosa , Paolo Natoli , Fabio Finelli , Francesco Paci

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
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