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Related papers: Universe opacity and cosmic dynamics

200 papers

I present the results of a new approach to the intensity and photon density spectrum of the intergalactic background light as a function of redshift using observational data obtained in many different wavelength bands from local to deep…

High Energy Astrophysical Phenomena · Physics 2013-02-11 Floyd W. Stecker

Expansion dynamics of the Universe is one of the important subjects in modern cosmology. The dark energy equation of state determines this dynamics so that the Universe is in an accelerating phase. However, the dark matter can also affect…

General Relativity and Quantum Cosmology · Physics 2025-10-08 Zeinab Rezaei

Recent astronomical observations indicate that the Universe is presently almost flat and undergoing a period of accelerated expansion. Basing on Einstein's general relativity all these observations can be explained by the hypothesis of a…

Astrophysics · Physics 2007-06-13 Marek Szydlowski , Aleksandra Kurek , Adam Krawiec

Probing the geometry of the universe is one of the most important endevours in cosmology. Current observational data from the Cosmic Microwave Background anisotropy (CMB), galaxy surveys and type Ia supernovae (SNe Ia) strongly constrain…

Astrophysics · Physics 2008-12-18 Laura Mersini-Houghton , Yun Wang , Pia Mukherjee , Ervin Kafexhiu

Distance-redshift diagrams probe expansion history of the Universe. We show that the stellar mass-binding energy (massE) relation of galaxies proposed in our previous study offers a new distance ruler at cosmic scales. By using elliptical…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-05 Yong Shi , Yanmei Chen , Shude Mao , Qiusheng Gu , Tao Wang , Xiaoyang Xia , Zhi-Yu Zhang

A Universe with finite age also has a finite causal scale. Larger scales can not affect our local measurements or modeling, but far away locations could have different cosmological parameters. The size of our causal Universe depends on the…

General Physics · Physics 2020-04-17 Enrique Gaztanaga

Degeneracy effects for bosons are more important for smaller particle mass, smaller temperature and higher number density. Bose condensation requires that particles be in the same lowest energy quantum state. We propose a cosmic background…

General Physics · Physics 2013-06-17 Antonio Alfonso-Faus , Màrius Josep Fullana i Alfonso

We have derived new bounds on the relativistic energy density in the Universe from cosmic microwave background (CMB), large scale structure (LSS), and type Ia supernova (SNI-a) observations. In terms of the effective number of neutrino…

Astrophysics · Physics 2009-11-13 Steen Hannestad

We derive Galactic continuum spectra from 5-96/cm from COBE/FIRAS observations. The spectra are dominated by warm dust emission, which may be fit with a single temperature in the range 16-21 K (for nu^2 emissivity) along each line of sight.…

Correctly interpreting observations of sources such as type Ia supernovae (SNe Ia) require knowledge of the power spectrum of matter on AU scales - which is very hard to model accurately. Because under-dense regions account for much of the…

Cosmology and Nongalactic Astrophysics · Physics 2013-11-22 V. C. Busti , R. F. L. Holanda , C. Clarkson

In this paper, we present a scheme to investigate the opacity of the Universe in a cosmological-model-independent way, with the combination of current and future measurements of type Ia supernova sample and galactic-scale strong…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-08 Yu-Bo Ma , Shuo Cao , Jia Zhang , Jingzhao Qi , Tonghua Liu , Yuting Liu , Shuaibo Geng

In cosmology based on general relativity, the universe is modeled as a fluid. The transition from the Einstein field equation to its large-scale (cosmological) version is thus analogous to the transition, for a system consisting of a large…

General Physics · Physics 2018-10-18 Gregory Ryskin

We investigate the evolution of interstellar dust in the Universe by means of chemical evolution models of galaxies of different morphological types, reproducing the main observed features of present day galaxies. We adopt the most updated…

Astrophysics of Galaxies · Physics 2017-09-06 Lorenzo Gioannini , Francesca Matteucci , Francesco Calura

Dark energy is one of the mysteries of modern science. It is unlike any known form of matter or energy and has been detected so far only by its gravitational effect of repulsion. Owing to its effects being discernible only at very very…

Cosmology and Nongalactic Astrophysics · Physics 2009-08-25 Aruna Kesavan

Recent optical observations have led to a significant progress in our understanding of galaxy formation and evolution. However, our view on the deep universe is currently limited to the starlight which directly escapes from high-redshift…

Astrophysics · Physics 2007-05-23 B. Guiderdoni

Old and new puzzles of cosmology are reexamined from the point of view of quantum theory of the universe developed here. It is shown that in proposed approach the difficulties of the standard cosmology do not arise. The theory predicts the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 V. E. Kuzmichev , V. V. Kuzmichev

Imagine a scenario in which the dark energy forms via the condensation of dark matter at some low redshift. The Compton wavelength therefore changes from small to very large at the transition, unlike quintessence or metamorphosis. We study…

Astrophysics · Physics 2009-11-07 Bruce A. Bassett , Martin Kunz , David Parkinson , Carlo Ungarelli

Recent astronomical observations of SNIa, CMB, as well as BAO in the Sloan Digital Sky Survey, suggest that the current Universe has entered a stage of an accelerated expansion with the transition redshift at $z \simeq 0.5$. While the…

Astrophysics · Physics 2010-11-11 Aleksandra Kurek , Marek Szydlowski

Observations show that the expansion of the Universe is accelerating. This requires that the dominant constituent of matter in the Universe has some unusual properties like negative pressure. This exotic component has been given the name…

Popular Physics · Physics 2019-01-17 Manvendra Pratap Rajvanshi , Tuneer Chakraborty , J. S. Bagla

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