Schelling Points and the Planck Frequency Comb

PSETI Seminar

Jason Wright
October 8, 2020

Abstract:
In SETI, when searching for "beacons"—transmissions intended for us and meant to get our attention—one must guess the appropriate frequency to search by considering what frequencies would be universally obvious to other species. This is a well known concept in game theory, where such solutions to a non-communicative cooperative game (such as a mutual search) are called "Schelling points." It is noteworthy, therefore, that when developing his eponymous units, Planck called them "natural" because they "remain meaningful for all times and also for extraterrestrial and non-human cultures."
I discuss how one might apply Planck's suggestion in the context of Schelling points in SETI with a "Planck Frequency Comb," constructed by multiplying the Planck energy by integer powers of the fine structure constant. This comb includes a small number of frequencies in regions of the electromagnetic spectrum where laser and radio SETI typically operates.
I will discuss the search implications of this line of reasoning, including the possibility of multi-modal communication, the anthropocentrism and arbitrariness of the comb, and the utility of "magic frequencies" in an era of broadband high resolution radio spectroscopy.