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Observational constraints on undulant cosmologies [PDF]
Journal of Cosmology and Astroparticle Physics, 2006 19 pages, 12 figures in 19 files, uses iopart.cls, iopart10.clo; added ...
Barenboim, Gabriela +2 more
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Space and observers in cosmology [PDF]
Astronomy & Astrophysics, 2001 I provide a prescription to define space, at a given moment, for an arbitrary observer in an arbitrary (sufficiently regular) curved space-time. This prescription, based on synchronicity (simultaneity) arguments, defines a foliation of space-time, which corresponds to a family of canonically associated observers.
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Observational aspects of an inhomogeneous cosmology [PDF]
Proceedings of VIII International Workshop on the Dark Side of the Universe — PoS(DSU 2012), 2013 One of the biggest mysteries in cosmology is Dark Energy, which is required to explain the accelerated expansion of the universe within the standard model. But maybe one can explain the observations without introducing new physics, by simply taking one step back and re-examining one of the basic concepts of cosmology, homogeneity. In standard cosmology,
Christoph Saulder +2 more
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Dark Matter and Galaxy Formation: Challenges for the Next Decade [PDF]
, 2004 The origin of the galaxies represents an important focus of current cosmological research, both observational and theoretical. Its resolution involves a comprehensive understanding of star formation, galaxy dynamics, the cosmology of the very early ...
Silk, Joseph
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Highly Accreting Supermassive Black Holes as Eddington Standard Candles
Physical Sciences Forum, 2023 Supermassive black holes accreting matter at very high, perhaps even super-Eddington rates appear in the sky as a special class of luminous active galactic nuclei.
Paola Marziani
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Temporal and Spectral Variability of OJ 287 before the April–June 2020 Outburst
Galaxies, 2020 We present the results of a temporal and spectral study of the BL Lacertae object OJ 287 in optical, UV, and X-ray bands with observations performed by Swift satellite during September 2019–March 2020.
Nibedita Kalita +2 more
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Observational Constraints on Cosmological Superstrings [PDF]
Theoretical Physics, 2017 From theoretical point of view and not being in contradiction with current observational data, the cosmic strings should have fundamentally different origin and are characterized by wide range of energies. The paper is devoted to search for possible cosmological observational tests on superstring theory, among them to identification of observational ...
O. S. Sazhina, Alfiia I. Mukhaeva
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4 Observational Cosmology [PDF]
, 2004 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 physicists, with emphasis upon the possible systematic uncertainties in the observations and their interpretation ...
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The current status of observational cosmology [PDF]
, 2004 Observational cosmology has indeed made very rapid progress in recent years. The ability to quantify the universe has largely improved due to observational constraints coming from structure formation.
A A Starobinsky +42 more
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Observational Cosmology with Artificial Neural Networks
Universe, 2022 In cosmology, the analysis of observational evidence is very important when testing theoretical models of the Universe. Artificial neural networks are powerful and versatile computational tools for data modelling and have recently been considered in the ...
Juan de Dios Rojas Olvera +2 more
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