SMuK 2021 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

GR: Fachverband Gravitation und Relativitätstheorie

GR 2: Classical GR-1

GR 2.1: Invited Talk

Tuesday, August 31, 2021, 11:00–11:45, H6

The Sagnac effect in General Relativity — •Jörg Frauendiener — University of Otago, Dunedin, New Zealand

The Sagnac effect can be described as the difference in travel time between two photons traveling along the same path in opposite directions. In this talk we explore the consequences of this characterisation in the context of General Relativity. We derive a general expression for this time difference in an arbitrary space-time for arbitrary paths. In general, this formula is not very useful since it involves solving a differential equation along the path. However, we also present special cases where a closed form expression for the time difference can be given. We discuss the effect in a small neighbourhood of an arbitrarily moving observer in their arbitrarily rotating reference frame. Time permitting we may also discuss the special case of stationary space-times and point out the relationship between the Sagnac effect and Fizeau's ``aether-drag'' experiment.