Results 1 to 10 of about 90,199 (336)

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 ...
Gianluca Calcagni
openalex   +5 more sources

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

Observational exclusion of a consistent loop quantum cosmology scenario [PDF]

, 2016
It is often argued that inflation erases all the information about what took place before it started. Quantum gravity, relevant in the Planck era, seems therefore mostly impossible to probe with cosmological observations.
Boris Bolliet, Aurélien Barrau, Julien Grain, Susanne Schander   +3 more
openalex   +5 more sources

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
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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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The DESI Survey Validation: Results from Visual Inspection of Bright Galaxies, Luminous Red Galaxies, and Emission-line Galaxies

The Astrophysical Journal, 2023
The Dark Energy Spectroscopic Instrument (DESI) Survey has obtained a set of spectroscopic measurements of galaxies to validate the final survey design and target selections.
Ting-Wen Lan, R. Tojeiro, E. Armengaud, J. Xavier Prochaska, T. M. Davis, David M. Alexander, A. Raichoor, Rongpu Zhou, Christophe Yèche, C. Balland, S. BenZvi, A. Berti, R. Canning, A. Carr, H. Chittenden, S. Cole, M.-C. Cousinou, K. Dawson, Biprateep Dey, K. Douglass, A. Edge, S. Escoffier, A. Glanville, S. Gontcho A Gontcho, J. Guy, C. Hahn, C. Howlett, Ho Seong Hwang, L. Jiang, A. Kovács, M. Mezcua, S. Moore, S. Nadathur, M. Oh, D. Parkinson, A. Rocher, A. J. Ross, V. Ruhlmann-Kleider, C. G. Sabiu, K. Said, C. Saulder, D. Sierra-Porta, B. Weiner, J. Yu, P. Zarrouk, Y. Zhang, H. Zou, S. Ahlen, S. Bailey, D. Brooks, A. P. Cooper, A. de la Macorra, A. Dey, G. Dhungana, P. Doel, S. Eftekharzadeh, K. Fanning, A. Font-Ribera, L. Garrison, E. Gaztañaga, R. Kehoe, T. Kisner, A. Kremin, M. Landriau, L. Le Guillou, Michael E. Levi, C. Magneville, Aaron M. Meisner, R. Miquel, J. Moustakas, Adam D. Myers, Jeffrey A. Newman, J. D. Nie, N. Palanque-Delabrouille, W. J. Percival, C. Poppett, F. Prada, M. Schubnell, Gregory Tarlé, B. A. Weaver, K. Zhang, Zhimin Zhou   +81 more
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Observational constraints on soft dark energy and soft dark matter: Challenging ΛCDM cosmology

Nuclear Physics B, 2023
Soft cosmology is an extension of standard cosmology allowing for a scale-dependent equation-of-state (EoS) parameter in the dark sectors, which is one of the properties of soft materials in condensed-matter physics, that may arise either intrinsically ...
Emmanuel N. Saridakis, Weiqiang Yang, Supriya Pan, Fotios K. Anagnostopoulos, Spyros Basilakos   +4 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
core   +3 more sources