Marek Abramowicz (University of Gothenburg, Sweden)
Title: How to search for a signal from alien civilizations?
Summary: I argue that sufficiently advanced alien civilizations would construct a very special type of transmitter, with unique properties that I describe, to signal their presence to the whole Galaxy.
Nishanth Gudapati (CSMA Fellow, Harvard)
Title: Gravitational Lensing for Stationary Spacetimes: A Finsler Geometry Approach
Abstract: A goal of the mathematical studies of gravitational lensing is to establish a relation between observables using geometric and topological information of the optical metric. In the work of Gibbons-Werner (2008), such a relation is established between the deflection angle of observation and the Gauss curvature of the optical metric of a static spacetime. Subsequently, this result was extended to a relation between the deflection angle and the geometric mass of the static spacetime. In view of the fact that the corresponding optical geometry of static spacetimes is Riemannian, the Gauss-Bonnet theorem was used in a fundamental way. In contrast with static spacetimes, the optical metric for stationary spacetimes is of Randers-Finsler type. In this talk we shall discuss some results on Finsler geometry approach for gravitational lensing in stationary spacetimes. Joint with Marcus Werner (Kyoto University).