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Observational test of quantum cosmology [PDF]

Physical Review D, 2000
15 pages RevTex, including two postscript figure files. Revised to extend range of Coleman De Luccia theories considered and to include models with a cosmological ...
Steven Gratton, Thomas Hertog, Neil Turok   +2 more
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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   +3 more sources

Supernovae - a tool for observational cosmology [PDF]

Proceedings of XII Multifrequency Behaviour of High Energy Cosmic Sources Workshop — PoS(MULTIF2017), 2018
Type Ia Supernovae (SNe) are excellent distance indicators in the Universe. Observations of distant SNe~Ia led to the discovery of the accelerating expansion of the Universe. The most recent analysis of SNe Ia indicates that considering a flat $\Lambda$CDM cosmology, the contribution of dark energy in the total density of the Universe is $\sim$70 ...
M. V. Pruzhinskaya, P.-F. Léget
openalex   +2 more sources

Observations in quantum cosmology

Classical and Quantum Gravity, 2023
AbstractIn this review, we focus on whether a canonical quantization of general relativity can produce testable predictions for cosmology. In particular, we examine how this approach can be used to model the evolution of primordial perturbations.
Leonardo Chataignier, Claus Kiefer, Paulo Moniz   +2 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

Revisiting geodesic observers in cosmology [PDF]

The European Physical Journal C, 2021
AbstractGeodesic observers in cosmology are revisited. The coordinates based on freely falling observers introduced by Gautreau in de Sitter and Einstein-de Sitter spaces (and, previously, by Gautreau and Hoffmann in Schwarzschild space) are extended to general FLRW universes.
Geneviève Vachon, Robert Vanderwee, Valerio Faraoni   +2 more
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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
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Observational Cosmology [PDF]

Proceedings of European Physical Society Conference on High Energy Physics — PoS(EPS-HEP2019), 2020
Despite the title, I am afraid that I will not be able to really do justice to the broad topic I was given to review. But I will show the current striking level of precise consistency between the CMB and LSS data \textit{within the \LCDM\ theoretical framework} (with the acronyms CMB and LSS standing for Cosmic Microwave Background and Large Scale ...
openaire   +2 more sources

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
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Low-Redshift Observational Constraints on Dark Energy Cosmologies [PDF]

Iranian Journal of Astronomy and Astrophysics, 2023
Applying the Markov chain Monte Carlo algorithm and using low-redshift observational data, we put cosmological constraints on dark energy cosmologies. Our main aim is to show the influence of each data sample on the procedure of constraining.
Mohammad Malekjani
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