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Related papers: Geocentrism reexamined

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We discuss the question to what degree the geometrical structure and the matter content of the universe at scales exceeding the present Hubble horizon is constrained by cosmological observations, in particular by measurements of the cosmic…

Astrophysics · Physics 2007-05-23 G. Dautcourt

Assuming the universe is spatially homogeneous on the largest scales lays the foundation for almost all cosmology. This idea is based on the Copernican principle, that we are not at a particularly special place in the universe.…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Chris Clarkson

The high Galactic latitude sky at millimeter and submm wavelengths contains significant cosmological information about the early Universe (in terms of the cosmic microwave background) but also the process of structure formation in the…

Cosmology and Nongalactic Astrophysics · Physics 2010-09-16 Luca Conversi , Paola Fiadino , Paolo de Bernardis , Silvia Masi

We present new observational constraints on inhomogeneous models based on observables independent of the CMB and large-scale structure. Using Bayesian evidence we find very strong evidence for the homogeneous LCDM model, thus disfavouring…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Roland de Putter , Licia Verde , Raul Jimenez

We extend our previous work on the cosmology of Coleman-de Luccia bubble collisions. Within a set of approximations we calculate the effects on the cosmic microwave background (CMB) as seen from inside a bubble which has undergone such a…

High Energy Physics - Theory · Physics 2010-04-28 Spencer Chang , Matthew Kleban , Thomas S. Levi

I describe the imprint of primordial magnetic fields on the CMB. I show that these are observable only if the field amplitude is of the order of $B\gsim 10^{-9}G$ on Mpc scale. I further argue that such fields are strongly constrained by…

Astrophysics · Physics 2008-11-26 Ruth Durrer

The current suite of results from Cosmic Microwave Background anisotropy experiments is fulfilling the promise of providing extraordinary levels of discrimination between cosmological models. We calculate a binned anisotropy power spectrum,…

Astrophysics · Physics 2007-05-23 Elena Pierpaoli , Douglas Scott , Martin White

Outside galaxy clusters the competition between the inwards gravitational attraction and the outwards expansion of the Universe leads to a special radius of velocity cancellation, which is called the turn-around radius. Measurements of the…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-02 Steen H. Hansen , Farbod Hassani , Lucas Lombriser , Martin Kunz

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…

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

The blackbody radiation left over from the Big Bang has been transformed by the expansion of the Universe into the nearly isotropic 2.73K Cosmic Microwave Background. Tiny inhomogeneities in the early Universe left their imprint on the…

Several anomalies have been identified which may imply a breakdown of the statistical isotropy of the cosmic microwave background (CMB). In particular, an anomalous alignment of the quadrupole and octopole and a hemispherical power…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Hiranya V. Peiris , Tristan L. Smith

The current cosmological dark sector (dark matter plus dark energy) is challenging our comprehension about the physical processes taking place in the Universe. Recently, some authors tried to falsify the basic underlying assumptions of such…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 V. C. Busti , J. A. S. Lima

A new map of the sky representing the degree of randomness in the cosmic microwave background (CMB) temperature has been obtained. The map based on estimation of the Kolmogorov stochasticity parameter clearly distinguishes the contribution…

Cosmic microwave background (CMB) anisotropies and density fluctuations are calculated for flat cold dark matter (CDM) models with a wide range of parameters, i.e., $\Omega_0, h$ and $\Omega_B$ for both standard recombination and various…

Astrophysics · Physics 2009-10-22 Naoshi Sugiyama

We consider structure formation and CMB anisotropies in a closed universe, both with and without a cosmological constant. The CMB angular power spectrum and the matter transfer function are presented, along with a discussion of their…

Astrophysics · Physics 2009-08-18 Martin White , Douglas Scott

The cosmic microwave background (CMB) offers a unique window into the early universe, providing insights into cosmological parameters like the Hubble constant. Recent precise measurements of the CMB by experiments like Planck seem to point…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-26 Pablo Lemos , Paul Shah

Large-scale cosmic microwave background anisotropies in homogeneous, globally anisotropic cosmologies are investigated. We perform a statistical analysis in which the four-year data from the Cosmic Background Explorer satellite is searched…

Astrophysics · Physics 2008-11-26 Emory. F. Bunn , Pedro Ferreira , Joseph Silk

A fundamental assumption in cosmology is that of statistical isotropy - that the universe, on average, looks the same in every direction in the sky. Statistical isotropy has recently been tested stringently using Cosmic Microwave Background…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-14 Caroline Zunckel , Dragan Huterer , Glenn D. Starkman

A large lepton asymmetry in the Universe is still a viable possibility and leads to many interesting phenomena such as gauge symmetry nonrestoration at high temperature. We show that a large lepton asymmetry changes the predicted cosmic…

High Energy Physics - Phenomenology · Physics 2009-10-31 William H. Kinney , Antonio Riotto
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