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Observational Cosmology with Artificial Neural Networks [PDF]
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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Machine learning for observational cosmology [PDF]
Reports on Progress in Physics, 2023 Abstract An array of large observational programs using ground-based and space-borne telescopes is planned in the next decade. The forthcoming wide-field sky surveys are expected to deliver a sheer volume of data exceeding an exabyte.
, Takahiro Nishimichi, Kana Moriwaki
exaly +5 more sources
Observational constraints on the fractal cosmology [PDF]
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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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
openaire +2 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
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Predicting cosmological observables with PyCosmo
Astronomy and Computing, 2021 Astronomy and Computing ...
Federica Tarsitano +9 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 +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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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.
openaire +2 more sources
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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