English
Related papers

Related papers: The Olbers Conjecture, Revisited

200 papers

The observed extragalactic background light (EBL) is affected by light attenuation due to absorption of light by galactic and intergalactic dust in the Universe. Even galactic opacity of 10-20 percent and minute universe intergalactic…

Astrophysics of Galaxies · Physics 2016-11-21 Vaclav Vavrycuk

The Tolman test for surface brightness dimming was originally proposed as a test for the expansion of the Universe. The test, which is independent of the details of the assumed cosmology,is based on comparisons of the surface brightness…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-06 Eric J. Lerner , Renato Falomo , Riccardo Scarpa

We propose a new method that can be used to constrain the properties of the Galactic bar (bulge). If the majority of the lensing objects are in the Galactic bar, then we predict a systematic offset in the apparent magnitude between lensed…

Astrophysics · Physics 2009-10-22 K. Z. Stanek

Stars accrete near invisible hydrogen dominated agglomerates. This population, the `dark matter,' effects the nature of stars. Measurements show plasma streams impacting Earth, planets, Sun and stars. This mass-energy source contradicts…

Astrophysics · Physics 2007-05-23 Maurice Dubin , Robert K. Soberman

It is commonly stated that we have entered the era of precision cosmology in which a number of important observations have reached a degree of precision, and a level of agreement with theory, that is comparable with many Earth-based physics…

General Physics · Physics 2011-10-31 Marie-Noëlle Célérier

Gamma-Ray Bursts (GRBs) are the brightest sources in the universe, emit mostly in the hard X-ray energy band and have been detected at redshifts up to ~8.1. Thus, they are in principle very powerful probes for cosmology. I shortly review…

Cosmology and Nongalactic Astrophysics · Physics 2009-08-11 L. Amati

Mankind has not yet explained dark matter, the accelerating expansion of the Universe, the 'knee' and 'ankle' of the cosmic ray energy spectrum graph, the low star formation rates of low surface brightness (LSB) dwarf galaxies, the ignition…

Astrophysics · Physics 2007-05-23 Jerome Drexler

Modelling techniques for the propagation of light pollution in the atmosphere allow the computation of maps of artificial night sky brightness in any direction of the sky, involving a large number of details from satellite data. Cinzano et…

Instrumentation and Methods for Astrophysics · Physics 2020-07-02 Pierantonio Cinzano , Fabio Falchi

We describe the use of partially overlapping galaxies to provide direct measurements of the effective absorption in galaxy disks, independent of assumptions about internal disk structure. The non-overlapping parts of the galaxies and…

Astrophysics · Physics 2007-05-23 Raymond E. White , William C. Keel , Christopher J. Conselice

I discuss the classical cosmological tests-- angular size-redshift, flux-redshift, and galaxy number counts-- in the light of the cosmology prescribed by the intepretation of CMB anisotropies. The discussion is somewhat of a primer for…

Astrophysics · Physics 2015-06-24 R. H. Sanders

There are many theories that have resided these last fifty years within the hazy mist we have been calling the Standard Model (SM) of elementary particles. An attempt is made here to construct a coherent description of the SM today, because…

History and Philosophy of Physics · Physics 2019-11-25 James D. Wells

Forecasting optical turbulence in the Earth's atmosphere has been an ambitious challenge for the astronomical scientific community for several decades. While earlier research primarily focused on whether it was possible to predict optical…

Instrumentation and Methods for Astrophysics · Physics 2025-10-27 Elena Masciadri , Alessio Turchi , Camilo Weinberger , Marlene De Sepibus , Luca Fini

We use large-scale cosmological simulations to estimate the mass-to-light ratio of galaxy systems as a function of scale, and compare the results with observations of galaxies, groups, clusters, and superclusters of galaxies. We find…

Astrophysics · Physics 2016-08-15 N. A. Bahcall , R. Cen , R. Davé , J. P. Ostriker , Q. Yu

We demonstrate a new technique to search for dark compact objects. When dark matter comprising a dark compact object interacts with photons, the compact object can disperse light traveling though it. As these objects pass between Earth and…

High Energy Physics - Phenomenology · Physics 2025-04-09 Joseph Bramante , Melissa D. Diamond , J. Leo Kim

Galaxies represent the visible fabric of the Universe and there has been considerable progress recently in both observational and theoretical studies. The underlying goal is to understand the present-day diversity of galaxy forms, masses…

Astrophysics · Physics 2007-05-23 Richard S Ellis

The "new standard cosmology", based on the theory of inflation, has very impressive observational support. I review some outstanding problems of the new cosmology and the global view of the universe -- the multiverse -- that it suggests. I…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Alexander Vilenkin

The universe is composed of ordinary matter (for example, stars, planets, ourselves), dark matter and dark energy. The estimated percentage of dark matter is about $27\%$ of the entire universe, while $5\%$ is ordinary matter and the…

Popular Physics · Physics 2023-06-05 Alessandra Celletti

Prior to the 1990s, speculations about the occurrence of planets around other stars were based only on planet formation theory, observations of circumstellar disks, and the knowledge that at least one seemingly ordinary star had managed to…

Earth and Planetary Astrophysics · Physics 2018-09-26 Joshua N. Winn

The discovery of the accelerating universe indicates strongly the presence of a scalar field which is not only expected to solve today's version of the cosmological constant problem, or the fine-tuning and the coincidence problems, but also…

General Relativity and Quantum Cosmology · Physics 2010-02-24 Yasunori Fujii , Kensuke Homma

I review the constraints imposed by the observed extragalactic background light (EBL) on the history of the stellar birthrate in galaxies. At faint magnitudes, the logarithmic slope of the galaxy counts is flatter than 0.4 in all seven…

Astrophysics · Physics 2009-10-31 Piero Madau