Via Mihai Patrascu, a paper that was accepted at STOC about communicating with aliens … here.

Excerpt:

Consider the following scenario: Alice, an extraterrestrial, decides to initiate contact with a terrestrial
named Bob by means of a radio wave transmission. How should he respond to her? Will he
ever be able to understand her message? In this paper we explore such scenarios by framing the
underlying questions computationally.