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Power spectra and cross-correlation measurements from the weak gravitational lensing of the cosmic microwave background (CMB) and the cosmic shearing of faint galaxies images will help shed light on quantities hidden from the CMB…

天体物理学 · 物理学 2009-07-09 Wayne Hu

We generalize the treatment of inflationary perturbations to deal with the non-Markovian colored noise emerging from any realistic approach to stochastic inflation. We provide a calculation of the power-spectrum of the gauge-invariant…

天体物理学 · 物理学 2009-11-10 M. Liguori , S. Matarrese , M. Musso , A. Riotto

We investigate the power spectrum of the distortion of Cosmic Microwave Background (CMB) due to the decay of the primordial magnetic fields. It is known that there are two-types of the CMB distortions, so-called \mu- and y-types and we find…

宇宙学与河外天体物理 · 物理学 2014-03-12 Koichi Miyamoto , Toyokazu Sekiguchi , Hiroyuki Tashiro , Shuichiro Yokoyama

We investigate weak lensing effect on cosmic microwave background (CMB) in the presence of dipole anisotropy. The approach of flat-sky approximation is considered. We determine the functions $\sigma_0^2$ and $\sigma_2^2$ that appear in…

宇宙学与河外天体物理 · 物理学 2019-07-24 Abhineet Agarwal , Naveen K. Singh , Pankaj Jain , Prabhakar Tiwari

The low quadrupole of the cosmic microwave background (CMB), measured by COBE and confirmed by WMAP, has generated much discussion recently. We point out that the well-known correlation between temperature and polarization anisotropies of…

天体物理学 · 物理学 2009-06-15 Olivier Doré , Gilbert P. Holder , Abraham Loeb

We consider the influence of the dark energy dynamics at the onset of cosmic acceleration on the Cosmic Microwave Background (CMB) bispectrum, through the weak lensing effect induced by structure formation. We study the line of sight…

天体物理学 · 物理学 2009-11-10 F. Giovi , C. Baccigalupi , F. Perrotta

Cosmic microwave background anisotropies encode crucial information about the early Universe and fundamental cosmological physics. Although the standard $\Lambda$CDM model provides a successful description of cosmic evolution, persistent…

宇宙学与河外天体物理 · 物理学 2026-05-05 Yang Han , Lu Chen , Guo-Hao Li , Pei-Yuan Xu

Effect of non-canonical scalar fields on the CMB imprints of the anisotropic inflation will be discussed in details in this paper. In particular, we are able to obtain the general formalism of the angular power spectra in the scalar…

广义相对论与量子宇宙学 · 物理学 2021-05-07 Tuan Q. Do , W. F. Kao , Ing-Chen Lin

Using the exact Lemaitre-Bondi-Tolman solution with a non-vanishing cosmological constant $\Lambda$, we investigate how the presence of a local spherically-symmetric inhomogeneity can affect apparent cosmological observables, such as the…

宇宙学与河外天体物理 · 物理学 2015-09-01 Antonio Enea Romano , Misao Sasaki , Alexei A. Starobinsky

We investigate the weak lensing corrections to the CMB temperature and polarization anisotropies. We consider all the effects beyond the leading order: post-Born corrections, LSS corrections and, for the polarization anisotropies, the…

宇宙学与河外天体物理 · 物理学 2018-07-26 Giovanni Marozzi , Giuseppe Fanizza , Enea Di Dio , Ruth Durrer

Recent observations have identified a significant 4.9$\sigma$ tension between the cosmic dipole inferred from galaxy number counts and that derived from the Cosmic Microwave Background (CMB), suggesting a potential deviation from the…

宇宙学与河外天体物理 · 物理学 2025-07-29 Ge Chen , Chengcheng Han , Linwei Qiu

This is a review of the Cold Dark Matter model of structure formation, and its variants. The approach is largely from first principles, the main aim being to impart a basic understanding of the relevant theory with an eye to the likely…

天体物理学 · 物理学 2010-11-30 Andrew R Liddle , David H Lyth

We study dependence of the CMB temperature anisotropy spectrum on the value of the fine structure constant $\alpha$ and the equation of state of the dark energy component of the total density of the universe. We find that bounds imposed on…

天体物理学 · 物理学 2014-10-13 Greg Huey , Stephon Alexander , Levon Pogosian

We study the consequences of a homogeneous dark energy fluid having a non-vanishing velocity with respect to the matter and radiation large-scale rest frames. We consider homogeneous anisotropic cosmological models with four fluids…

天体物理学 · 物理学 2008-11-26 Jose Beltran Jimenez , Antonio L. Maroto

We study the eigenmodes of the spin-2 Laplacian in orientable Euclidean manifolds and their implications for the tensor-induced part of the cosmic microwave background (CMB) temperature and polarization anisotropies. We provide analytic…

Low multipoles ($l$) in cosmic microwave background (CMB) temperature anisotropies have shown some `peculiarities' when examined since the release of the full sky CMB maps, using a variety of tests. In this paper, we concern ourselves with…

宇宙学与河外天体物理 · 物理学 2025-07-01 Pavan Kumar Aluri , Sanjeet Kumar Patel

We show that perturbations generated during the anisotropic pre-inflationary stage of cosmic evolution may affect cosmological observations today for a certain range of parameters. Due to the anisotropic nature of the universe during such…

宇宙学与河外天体物理 · 物理学 2017-09-15 Pavan K. Aluri , Pankaj Jain

We introduce a multifield dark energy model with a nonflat field-space metric, in which one field is dynamical while the others have constant spatial gradients. The model is predictive at the background level, leading to an early dark…

宇宙学与河外天体物理 · 物理学 2024-09-04 Juan P. Beltrán Almeida , Alejandro Guarnizo , Thiago S. Pereira , César A. Valenzuela-Toledo

The connection between the dipolar modulation asymmetry and the quadrupole-octopole alignment in the CMB is studied in this work. First, a generalization of the dipolar modulation model is proposed by considering that the amplitude may…

宇宙学与河外天体物理 · 物理学 2019-11-06 A. Marcos-Caballero , E. Martínez-González

The standard theoretical description $\Theta(\hat n)$ of the observed CMB temperature anisotropies is gauge-dependent. It is, however, well known that the gauge mode is limited to the monopole and the higher angular multipoles $\Theta_l$…

宇宙学与河外天体物理 · 物理学 2021-03-18 Sandra Baumgartner , Jaiyul Yoo