Cosmography beyond standard candles and rulers
نویسندگان
چکیده
منابع مشابه
Reconstructing Cosmological Matter Perturbations using Standard Candles and Rulers
For a large class of dark energy (DE) models, for which the effective gravitational constant is a constant and there is no direct exchange of energy between DE and dark matter (DM), knowledge of the expansion history suffices to reconstruct the growth factor of linearized density perturbations in the non-relativistic matter component on scales much smaller than the Hubble distance. In this pape...
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We measure the length of the baryon acoustic oscillation (BAO) feature, and the expansion rate of the recent Universe, from low-redshift data only, almost model independently. We make only the following minimal assumptions: homogeneity and isotropy, a metric theory of gravity, a smooth expansion history, and the existence of standard candles (supernovæ) and a standard BAO ruler. The rest is det...
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To illustrate the standard candle property of gamma-ray pulsars (and also to thereby confirm the recent first-principle calculation of pulsar gamma-ray emission), we “measure”, via the lightcurve fitting, three distances and one moment of inertia of some weak pulsars. We are not sure what the three distances are good for, but the measurement of the moment of inertia must be of interest for nucl...
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ژورنال
عنوان ژورنال: Physical Review D
سال: 2012
ISSN: 1550-7998,1550-2368
DOI: 10.1103/physrevd.85.043520