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Related papers: A bound on the cosmic opacity of unparticles from …

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A cosmological model, in which the cosmic microwave background (CMB) is a thermal radiation of intergalactic dust instead of a relic radiation of the Big Bang, is revived and revisited. The model suggests that a virtually transparent local…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-30 Vaclav Vavrycuk

We study the cosmological constraints on unparticle interactions and the temperature of the Universe for the case where unparticle states can be modelled as continuous mass particles with lifetime > 1s. By considering thermal background…

High Energy Physics - Phenomenology · Physics 2009-11-13 John McDonald

Since the measurements of COBE/FIRAS in the mid-90's we know that the energy spectrum of the cosmic microwave background (CMB) is extremely close to that of a perfect blackbody at an average temperature T0~2.726K. However, a number of…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-11 Jens Chluba

The relation between redshift and the CMB temperature, $T_{CMB}(z)=T_0(1+z)$ is a key prediction of standard cosmology, but is violated in many non-standard models. Constraining possible deviations to this law is an effective way to test…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 A. Avgoustidis , G. Luzzi , C. J. A. P. Martins , A. M. R. V. L. Monteiro

Observers have demonstrated that it is now feasible to measure the cosmic microwave background (CMB) temperature at high redshifts. We explore the possible constraints on cosmology which might ultimately be derived from such measurements.…

Astrophysics · Physics 2009-11-07 John M. LoSecco , Grant J. Mathews , Yun Wang

This work presents a detailed analysis of Cosmic Microwave Background (CMB) radiation intensity observations. The CMB is a relic of the Big Bang and its study greatly enhances our knowledge of cosmology. This work has led to new values for…

Astrophysics · Physics 2007-05-23 Henrik P. Nordberg , George F. Smoot

Departures of the energy spectrum of the cosmic microwave background (CMB) from a perfect blackbody probe a fundamental property of the universe -- its thermal history. Current upper limits, dating back some 25 years, limit such spectral…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-01 A. Kogut , M. H. Abitbol , J. Chluba , J. Delabrouille , D. Fixsen , J. C. Hill , S. P. Patil , A. Rotti

Recent papers have reported an unexplained cooling of CMB photons passing through galaxies in nearby cosmic filaments $z<0.02$ at the $>5\sigma$ level. Here we show for the first time that this effect is also present at higher redshifts…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-20 Juan Ignacio Domínguez Feldman , Luis A. Pereyra , Frode K. Hansen , Facundo Toscano , Diego Garcia Lambas

Following the pioneering observations with COBE in the early 1990s, studies of the cosmic microwave background (CMB) have focused on temperature and polarization anisotropies. CMB spectral distortions - tiny departures of the CMB energy…

Spatially fluctuating primordial magnetic fields (PMFs) inhomogeneously reheat the Universe when they dissipate deep inside the horizon before recombination. Such an energy injection turns into an additional photon temperature perturbation.…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-28 Shohei Saga , Atsuhisa Ota , Hiroyuki Tashiro , Shuichiro Yokoyama

We use an integral representation for nonthermal radiation, which is bounded from below and above, to describe the spectrum of the cosmic microwave background (CMB). The upper bound is given by the Rayleigh-Jeans law with a temperature…

Cosmology and Nongalactic Astrophysics · Physics 2019-05-15 Moorad Alexanian

A key assumption of the standard cosmological model is that the temperature of the cosmic microwave background (CMB) radiation scales with cosmological redshift $z$ as $T_{\rm CMB}(z) \propto (1+z)$ at all times after recombination at…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-10 J. Colin Hill , Boris Bolliet

Recent measurements of the temperature field of Cosmic Microwave Background (CMB) provide tantalising evidence for violation of Statistical Isotropy (SI) that constitutes a fundamental tenet of contemporary cosmology. CMB space based…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-08 Suvodip Mukherjee , Tarun Souradeep

We discuss the thermodynamic and dynamical properties of a variable dark energy model with density scaling as $\rho_x \propto (1+z)^{m}$, z being the redshift. These models lead to the creation/disruption of matter and radiation, which…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Philippe Jetzer , Crescenzo Tortora

Spectral distortions of the cosmic microwave background (CMB) provide stringent constraints on energy and entropy production in the post-BBN (Big Bang Nucleosynthesis) era. This has been used to constrain dark photon models with COBE/FIRAS…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-19 Jens Chluba , Bryce Cyr , Matthew C. Johnson

Cosmological models assuming the scale invariance of the macroscopic empty space show an accelerated expansion, without calling for some unknown particles. Several comparisons between models and observations (tests on distances, m-z…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-04 Andre Maeder

The discussion of cosmological parameters used to be a source of embarrassment to cosmologists. Today, measurements of the cosmological parameters are leading the way into the era of precision cosmology. The CMB temperature is measured to…

Astrophysics · Physics 2009-10-31 Michael S. Turner

High-contrast peaks in the cosmic microwave background (CMB) anisotropy can appear as unresolved sources to observers. We fit simulated CMB maps generated with a cold dark matter model to a set of unresolved features at instrumental…

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

The tremendous experimental progress in cosmic microwave background (CMB) temperature and polarization anisotropy studies over the last few years has helped establish a standard paradigm for cosmology at intermediate epochs and has…

Astrophysics · Physics 2011-05-12 Wayne Hu

Presuming that CMB photons are described by the deconfining phase of an SU(2) Yang-Mills theory with the critical temperature for the deconfining-preconfining phase transition matching the present CMB temperature $T_0\sim 2.725\,$K…

General Physics · Physics 2015-06-22 Ralf Hofmann
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