title: Measuring the speed of light with baryon acoustic oscillations.
abstract: In this Letter, we describe a new method to use baryon acoustic oscillations (BAO) to derive a constraint on the possible variation of the speed of light. The method relies on the fact that there is a simple relation between the angular diameter distance (D(A)) maximum and the Hubble function (H) evaluated at the same maximum-condition redshift, which includes speed of light c. We note the close analogy of the BAO probe with a laboratory experiment: here we have D(A) which plays the role of a standard (cosmological) ruler, and H^{-1}, with the dimension of time, as a (cosmological) clock. We evaluate if current or future missions such as Euclid can be sensitive enough to detect any variation of c.
authors: Institute of Physics, University of Szczecin, Wielkopolska 15, 70-451 Szczecin, Poland.
authors: Vincenzo
authors: V
authors: Salzano
authors: Institute of Physics, University of Szczecin, Wielkopolska 15, 70-451 Szczecin, Poland.|Copernicus Center for Interdisciplinary Studies, Sławkowska 17, 31-016 Kraków, Poland.
authors: Mariusz P
authors: MP
authors: Dąbrowski
authors: Fisika Teorikoaren eta Zientziaren Historia Saila, Zientzia eta Teknologia Fakultatea, Euskal Herriko Unibertsitatea, 644 Posta Kutxatila, 48080 Bilbao, Spain.
authors: Ruth
authors: R
authors: Lazkoz