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Observational Cosmology in Macroscopic Gravity [PDF]

Journal of Cosmology and Astroparticle Physics, 2012
We discuss the construction of cosmological models within the framework of Macroscopic Gravity (MG), which is a theory that models the effects of averaging the geometry of space-time on large scales.
Alan Coley, D.L. Wiltshire, D.L. Wiltshire, G.F.R. Ellis, K. Bolejko, R.J. van den Hoogen, R.M. Zalaletdinov, R.M. Zalaletdinov, Robert van den Hoogen, See special focus section in CQG on inhomogeneous cosmological models, T. Buchert, Timothy Clifton   +11 more
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Observational constraints on Rastall's cosmology [PDF]

The European Physical Journal C, 2013
Rastall's theory is a modification of General Relativity, based on the non-conservation of the stress-energy tensor. The latter is encoded in a parameter $\gamma$ such that $\gamma = 1$ restores the usual $\nabla_\nu T^{\mu\nu} = 0$ law.
A. Felice De, A. M. Velasquez-Toribio, A.G. Riess, A.Y. Kamenshchik, C. E. M. Batista, C.-P. Ma, C.E.M. Batista, D. Bertacca, G. Bertone, J.C. Fabris, J.C. Fabris, J.C. Fabris, J.C. Fabris, Júlio C. Fabris, M. Capone, M. Hicken, M. Li, M.H. Daouda, N.D. Birrell, O.F. Piattella, O.F. Piattella, O.F. Piattella, Oliver F. Piattella, P. Rastall, P. Rastall, R. Colistete, R.R. Caldwell, T. Clifton, V. Gorini, W. Zimdahl, W. Zimdahl, W. Zimdahl, W.S. Hipolito-Ricaldi   +32 more
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Observational constraints on Horava-Lifshitz cosmology [PDF]

Journal of Cosmology and Astroparticle Physics, 2009
We use observational data from Type Ia Supernovae (SNIa), Baryon Acoustic Oscillations (BAO), and Cosmic Microwave Background (CMB), along with requirements of Big Bang Nucleosynthesis (BBN), to constrain the cosmological scenarios governed by Horava ...
A. Castillo, A. Ghodsi, A. Ghodsi, A. Papazoglou, A. Wang, A. Wang, A. Wang, B. Chen, B. Chen, B. Chen, C. Appignani, C. Bogdanos, C. Charmousis, C. Clarkson, C. Germani, C. Pallis, C.G. Boehmer, C.M. Will, D. Blas, D. Capasso, D. Momeni, D. Orlando, D.J. Eisenstein, E. Kiritsis, E.L. Wright, E.N. Saridakis, E.O. Colgain, Emmanuel N Saridakis, F.-W. Shu, G. Barenboim, G. Calcagni, G. Leon, H. Nastase, H.W. Lee, I. Cho, J. Alexandre, J. Chen, J. Kluson, J. Kluson, J.M. Virey, K. Ichikawa, K. Ichikawa, K. Koyama, L. Iorio, L. Iorio, M. Botta-Cantcheff, M. Li, M. Minamitsuji, M.-I. Park, M.-I. Park, M.-I. Park, M.-I. Park, M.R. Setare, N. Varghese, P. Hořava, P. Hořava, P. Wu, R. Lazkoz, R.-G. Cai, R.-G. Cai, R.B. Mann, S. Carloni, S. Koh, S. Mukohyama, Sourish Dutta, Supernova Cosmology Project collaboration, T. Harko, T. Kobayashi, T. Nishioka, T. Suyama, T.P. Sotiriou, U.H. Danielsson, W. Hu, W.J. Percival ., WMAP collaboration, X. Gao, X. Gao, Y. Wang, Y.-F. Cai, Y.S. Myung, Y.S. Myung   +80 more
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Sample Variance in Cosmological Observations with a Narrow Field of View

The Astrophysical Journal, 2023
Surveys with a narrow field of view can play an important role in probing cosmology, but inferences from these surveys suffer from large sample variance, arising from random fluctuations around the cosmic mean.
Peter Espenshade, Jaiyul Yoo
doaj   +1 more source

The DESI Survey Validation: Results from Visual Inspection of the Quasar Survey Spectra

The Astronomical Journal, 2023
A key component of the Dark Energy Spectroscopic Instrument (DESI) survey validation (SV) is a detailed visual inspection (VI) of the optical spectroscopic data to quantify key survey metrics. In this paper we present results from VI of the quasar survey
David M. Alexander, Tamara M. Davis, E. Chaussidon, V. A. Fawcett, Alma X. Gonzalez-Morales, Ting-Wen Lan, Christophe Yèche, S. Ahlen, J. N. Aguilar, E. Armengaud, S. Bailey, D. Brooks, Z. Cai, R. Canning, A. Carr, S. Chabanier, Marie-Claude Cousinou, K. Dawson, A. de la Macorra, A. Dey, Biprateep Dey, G. Dhungana, A. C. Edge, S. Eftekharzadeh, K. Fanning, James Farr, A. Font-Ribera, J. Garcia-Bellido, Lehman Garrison, E. Gaztañaga, Satya Gontcho A Gontcho, C. Gordon, Stefany Guadalupe Medellin Gonzalez, J. Guy, Hiram K. Herrera-Alcantar, L. Jiang, S. Juneau, N. G. Karaçaylı, R. Kehoe, T. Kisner, A. Kovács, M. Landriau, Michael E. Levi, C. Magneville, P. Martini, Aaron M. Meisner, M. Mezcua, R. Miquel, P. Montero Camacho, J. Moustakas, Andrea Muñoz-Gutiérrez, Adam D. Myers, S. Nadathur, L. Napolitano, J. D. Nie, N. Palanque-Delabrouille, Z. Pan, W. J. Percival, I. Pérez-Ràfols, C. Poppett, F. Prada, César Ramírez-Pérez, C. Ravoux, D. J. Rosario, M. Schubnell, Gregory Tarlé, M. Walther, B. Weiner, S. Youles, Zhimin Zhou, H. Zou, Siwei Zou   +71 more
doaj   +1 more source

Performance of the Quasar Spectral Templates for the Dark Energy Spectroscopic Instrument

The Astronomical Journal, 2023
Millions of quasar spectra will be collected by the Dark Energy Spectroscopic Instrument (DESI), leading to a fourfold increase in the number of known quasars.
Allyson Brodzeller, Kyle Dawson, Stephen Bailey, Jiaxi Yu, A. J. Ross, A. Bault, S. Filbert, J. Aguilar, S. Ahlen, David M. Alexander, E. Armengaud, A. Berti, D. Brooks, E. Chaussidon, A. de la Macorra, P. Doel, K. Fanning, V. A. Fawcett, A. Font-Ribera, S. Gontcho A Gontcho, J. Guy, K. Honscheid, S. Juneau, R. Kehoe, T. Kisner, Anthony Kremin, Ting-Wen Lan, M. Landriau, Michael E. Levi, C. Magneville, Paul Martini, Aaron M. Meisner, R. Miquel, J. Moustakas, N. Palanque-Delabrouille, W. J. Percival, F. Prada, C. Ravoux, Graziano Rossi, C. Saulder, M. Siudek, Gregory Tarlé, B. A. Weaver, S. Youles, Zheng Zheng, Rongpu Zhou, Zhimin Zhou   +46 more
doaj   +1 more source

Observational constraints on the fractal cosmology

European Physical Journal C: Particles and Fields, 2022
In this paper, we explore a fractal model of the universe proposed by Calcagni (J High Energy Phys 03:120, 2010) for a power-counting renormalizable field theory living in a fractal spacetime.
Mahnaz Asghari, Ahmad Sheykhi
doaj   +1 more source

Reionization and Cosmology with 21 cm Fluctuations [PDF]

, 2009
Measurement of the spatial distribution of neutral hydrogen via the redshifted 21 cm line promises to revolutionize our knowledge of the epoch of reionization and the first galaxies, and may provide a powerful new tool for observational cosmology from ...
J. Stuart B. Wyithe, Miguel F. Morales, Rohlfs K, Röttgering HJA, Taylor GB   +4 more
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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 ...
openaire   +4 more sources

Observational effects from quantum cosmology [PDF]

, 2013
The status of quantum cosmologies as testable models of the early universe is assessed in the context of inflation. While traditional Wheeler-DeWitt quantization is unable to produce sizable effects in the cosmic microwave background, the more recent ...
Calcagni, Gianluca
core   +3 more sources