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相关论文: Dipole Anisotropy from an Entropy Gradient

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The Universe on scales $10-100~h^{-1}$ Mpc is dominated by a cosmic web of voids, filaments, sheets and knots of galaxy clusters. These structures participate differently in the global expansion of the Universe: from non-expanding clusters…

宇宙学与河外天体物理 · 物理学 2016-06-21 Krzysztof Bolejko , M. Ahsan Nazer , David L. Wiltshire

It is shown that the observed cmb dipole implies the existence of a center for the expansion of the universe, and that it can be explained by a combination of peculiar velocity and Hubble flow.

天体物理学 · 物理学 2007-10-30 Yukio Tomozawa

If gamma-ray bursts originate at cosmological distances then their angular distribution should exhibit a dipole in the direction of the solar motion relative to the cosmic microwave background. This is due to the combined effects of…

天体物理学 · 物理学 2009-10-22 Eyal Maoz

We consider the distortions of the cosmic microwave background (CMB) dipole anisotropy related to the primordial recombination radiation (PRR) and primordial $y$- and $\mu$-distortions. The signals arise due to our motion relative to the…

宇宙学与河外天体物理 · 物理学 2015-09-14 S. A. Balashev , E. E. Kholupenko , J. Chluba , A. V. Ivanchik , D. A. Varshalovich

We characterize the radial and angular variance of the Hubble flow in the COMPOSITE sample of 4534 galaxies, on scales in which much of the flow is in the nonlinear regime. With no cosmological assumptions other than the existence of a…

宇宙学与河外天体物理 · 物理学 2013-10-30 David L. Wiltshire , Peter R. Smale , Teppo Mattsson , Richard Watkins

The divergence of the momentum density field of the large scale structure generates a secondary anisotropy contribution to the Cosmic Microwave Background (CMB). While the effect is best described as a non-linear extension to the well-known…

天体物理学 · 物理学 2009-11-13 Asantha Cooray , Naoki Seto

A modified gravity involving a critical acceleration, as empirically established at galactic scales and successfully tested by data on supernovae of type Ia, can fit the measured multipole spectrum of anisotropy in the cosmic microwave…

广义相对论与量子宇宙学 · 物理学 2012-06-25 V. V. Kiselev

We employ Maximum Likelihood Estimators to examine the Pantheon+ catalogue of Type Ia supernovae for large scale anisotropies in the expansion rate of the Universe. The analyses are carried out in the heliocentric frame, the CMB frame, as…

宇宙学与河外天体物理 · 物理学 2025-06-02 Animesh Sah , Mohamed Rameez , Subir Sarkar , Christos Tsagas

The assumption of isotropy -- that the Universe looks the same in all directions on large scales -- is fundamental to the standard cosmological model. This model forms the building blocks of essentially all of our cosmological knowledge to…

宇宙学与河外天体物理 · 物理学 2022-12-29 Jessica A. Cowell , Suhail Dhawan , Hayley J. Macpherson

We have studied the cosmic microwave background (CMB) map looking for features beyond cosmological isotropy. We began by tiling the CMB variance map (which are produced by different smoothing scales) with stripes of different sizes along…

宇宙学与河外天体物理 · 物理学 2024-08-12 MohammadHossein Jamshidi , Abdolali Banihashemi , Nima Khosravi

Our local motion with respect to the cosmic frame of rest is believed to be dominantly responsible for the observed dipole anisotropy in the Cosmic Microwave Background Radiation (CMBR). We study the effect of this motion on the sky…

宇宙学与河外天体物理 · 物理学 2023-06-21 Gopal Kashyap , Naveen K. Singh , Khun Sang Phukon , Sarah Caudill , Pankaj Jain

The observed dipole anisotropy of the cosmic microwave background (CMB) temperature is much larger than the fluctuations observed on smaller scales and is dominated by the kinematic contribution from the Doppler shifting of the monopole due…

宇宙学与河外天体物理 · 物理学 2017-10-25 P. Daniel Meerburg , Joel Meyers , Alexander van Engelen

Several statistical anomalies in the CMB temperature anisotropies seem to defy the assumption of a homogeneous and isotropic universe. In particular, a dipole modulation has been detected both in WMAP and Planck data. We adapt the…

宇宙学与河外天体物理 · 物理学 2014-07-29 R. Fernández-Cobos , P. Vielva , D. Pietrobon , A. Balbi , E. Martínez-González , R. B. Barreiro

In the standard diffusive picture for transport of cosmic rays (CRs), a gradient in the CR density induces a typically small, dipolar anisotropy in their arrival directions. This has been widely advertised as a tool for finding nearby…

高能天体物理现象 · 物理学 2015-01-15 Philipp Mertsch , Stefan Funk

There is tentative evidence for a mismatch between the rest frames of matter and the cosmic microwave background, the "quasar dipole anomaly". We consider such a dipole in tilted anisotropic models, for a range of scenarios and sources:…

宇宙学与河外天体物理 · 物理学 2025-12-04 Alicia Martín , Constantinos Skordis , Deaglan J. Bartlett , Harry Desmond , Pedro G. Ferreira , Tariq Yasin

We explore the hemispherical asymmetry predicted in cosmic microwave background polarization when there is an asymmetry in temperature anisotropies due to primordial perturbations. We consider the cases of asymmetries due to adiabatic and…

宇宙学与河外天体物理 · 物理学 2015-05-20 M. H. Namjoo , A. A. Abolhasani , H. Assadullahi , S. Baghram , H. Firouzjahi , D. Wands

The dipole anisotropy in the Cosmic Microwave Background Radiation (CMBR) has given a peculiar velocity vector 370 km s$^{-1}$ along $l=264^\circ,b=48^\circ$. However, some other dipoles, for instance, from the number counts, sky brightness…

宇宙学与河外天体物理 · 物理学 2023-01-04 Ashok K. Singal

Surprisingly large spontaneous electric dipole moments recently observed in homonuclear niobium clusters below 100 K (Moro el. al. Science 300, 1265 (2003)) are explained using first-principles electronic structure calculations. The…

材料科学 · 物理学 2009-11-10 Kristopher Andersen , Vijay Kumar , Yoshiyuki Kawazoe , Warren Pickett

We present a determination of the cosmic microwave background dipole amplitude and direction from the COBE Differential Microwave Radiometers (DMR) first year of data. Data from the six DMR channels are consistent with a Doppler-shifted…

天体物理学 · 物理学 2009-10-22 A. Kogut , C. Lineweaver , G. F. Smoot , C. L. Bennett , A. Banday

We consider the imprints of local massive defects, such as a black hole or a massive monopole, during inflation. The massive defect breaks the background homogeneity. We consider the limit that the physical Schwarzschild radius of the…

宇宙学与河外天体物理 · 物理学 2016-10-19 Hassan Firouzjahi , Asieh Karami , Tahereh Rostami