Results 1 to 10 of about 2,376 (273)
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
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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 +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 +46 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
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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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, 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 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 +81 more
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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 ...
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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 +4 more
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Observations in quantum cosmology
Classical and Quantum Gravity, 2023 Abstract In 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. This program of quantum geometrodynamics, first advocated by John Wheeler and Bryce DeWitt,
Leonardo Chataignier +2 more
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