Measuring constancy of the speed of light by cosmological rulers and chronometers

The speed of light is one of the most fundamental physical constants entering variety of physical laws (e.g. Maxwell equations, relativistic equations, etc.). Nowadays, it is fixed by BIPM (Bureau International des Poids et Mesures) to be constant and reads 299792458 km/s. However, its constancy is questioned by the theories which allow it to vary (beginning from the one proposed by Einstein himself). In my talk I will present basic ideas of the varying speed of light cosmologies, its formulation, benefits and problems and relate them to the theories of varying fine structure constants. Then, I will discuss new tests (redshift drift and especially the angular diameter distance maximum related to Baryon Acoustic Oscillations) which may allow measuring timely and spatial change of the speed of light by using the future missions such as Euclid, SKA (Square Kilometer Array) or others.

Serdecznie zapraszamy,

E. Czuchry, E. Infeld, W. Piechocki, A. Pollo