Model-independent determination of the cosmic expansion rate

• Verfasst von: Mignone, Claudia [VerfasserIn]
• Verfasst von: Bartelmann, Matthias [VerfasserIn]
• Titel: Model-independent determination of the cosmic expansion rate
• Titelzusatz: I. application to type-Ia supernovae
• Verf.angabe: Claudia Mignone, and Matthias Bartelmann
• E-Jahr: 2017
• Jahr: April 27, 2017
• Umfang: 9 S.
• Fussnoten: Gesehen am 25.09.2017
• Titel Quelle: Enthalten in: De.arxiv.org
• Ort Quelle: [S.l.] : Arxiv.org, 1991
• Jahr Quelle: 2017
• Band/Heft Quelle: (2017) Artikel-Nummer 0711.0370, 9 Seiten
• Datenträger: Online-Ressource
• Sprache: eng
• Sach-SW: Astrophysics
• K10plus-PPN: 1563774364

Abstract

Aims: In view of the substantial uncertainties regarding the possible dynamics of the dark energy, we aim at constraining the expansion rate of the universe without reference to a specific Friedmann model and its parameters. Methods: We show that cosmological observables integrating over the cosmic expansion rate can be converted into a Volterra integral equation which is known to have a unique solution in terms of a Neumann series. Expanding observables such as the luminosity distances to type-Ia supernovae into a series of orthonormal functions, the integral equation can be solved and the cosmic expansion rate recovered within the limits allowed by the accuracy of the data. Results: We demonstrate the performance of the method applying it to synthetic data sets of increasing complexity, and to the first-year SNLS data. In particular, we show that the method is capable of reproducing a hypothetical expansion function containing a sudden transition.