Results 81 to 90 of about 3,180,538 (237)
Revisiting the Hubble Constant, Sound Horizon, and Cosmography from Late-time Universe Observations
The Astrophysical JournalThe Hubble tension has become one of the central problems in cosmology. In this work, we determine the Hubble constant H _0 and sound horizon r _d by using the combination of baryon acoustic oscillations (BAOs) from DESI surveys, time-delay lensed ...
Zhiwei Yang, Tonghua Liu, Xiaolei Li
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New Observational H(z) Data from Full-spectrum Fitting of Cosmic Chronometers in the LEGA-C Survey
The Astrophysical Journal Supplement Series, 2023 In this work, we perform a full-spectrum fitting of 350 massive and passive galaxies selected as cosmic chronometers from the LEGA-C ESO public survey to derive their stellar ages, metallicities, and star formation histories.
Kang Jiao +3 more
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Observational cosmology using characteristic numerical relativity [PDF]
, 2010 The characteristic formalism in numerical relativity, which has been developed to study gravitational waves, and the observer metric approach in observational cosmology both make use of coordinate systems based on null cones.
P. J. V. D. Walt, N. Bishop
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Observational constraints on loop quantum cosmology. [PDF]
Physical Review Letters, 2011 In the inflationary scenario of loop quantum cosmology in the presence of inverse-volume corrections, we give analytic formulas for the power spectra of scalar and tensor perturbations convenient to compare with observations.
M. Bojowald, G. Calcagni, S. Tsujikawa
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Light-cone observations and cosmological models: implications for inhomogeneous models mimicking dark energy [PDF]
arXiv, 2009 Cosmological observables are used to construct cosmological models. Since cosmological observations are limited to the light cone, a fixed number of observables (even measured to arbitrary accuracy) may not uniquely determine a cosmological model without additional assumptions or considerations.
arxiv
The Astrophysical Journal, 2023 In this paper, using the latest Pantheon+ sample of Type Ia supernovae, baryon acoustic oscillation measurements, and observational Hubble data, we carry out a joint constraint on the Hubble constant H _0 , the spatial curvature Ω _K , and the sound ...
Kaituo Zhang +4 more
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Observational constraints on Hubble constant and deceleration parameter in power-law cosmology [PDF]
, 2011 In this paper, we show that the expansion history of the Universe in power-law cosmology essentially depends on two crucial parameters, namely the Hubble constant $H_{0}$ and deceleration parameter $q$.
Suresh Kumar
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Observational test of inflation in loop quantum cosmology [PDF]
, 2011 We study in detail the power spectra of scalar and tensor perturbations generated during inflation in loop quantum cosmology (LQC). After clarifying in a novel quantitative way how inverse-volume corrections arise in inhomogeneous set- tings, we show ...
M. Bojowald, G. Calcagni, S. Tsujikawa
semanticscholar +1 more source
Cosmological models: Theory and observations [PDF]
Advances in Space Research, 2003 7 pages, invited talk at 33rd COSPAR Scientific Assembly (Warsaw, Poland, 16-23 July 2000), cospar.sty is ...
openaire +3 more sources
The Astrophysical Journal LettersDetermining the cosmic curvature (Ω _K ) independent of cosmological models plays a key role in revealing the background physics of our Universe. In this Letter, we propose an improved method to measure the cosmic curvature using the observations of ...
Tonghua Liu +4 more
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