The Cepheid galactic internet

Abstract

We propose that a sufficiently advanced civilisation may employ Cepheid variable stars as beacons to transmit all-call information throughout the galaxy and beyond. They might employ a pulsed neutrino beam to trigger the expansion of a Cepheid at an earlier than normal time, generating a binary signature of normal period or artificially shortened period. One can construct many scenarios wherein it would be desirable for such a civilisation of star ticklers to transmit data to anyone else within viewing range. The beauty of employing Cepheids is that these stars can be seen from afar (we monitor them out through the Virgo cluster), and any developing technological society would seem to be likely to closely observe them as distance markers. Records exist of Cepheids for well over 100 years. We propose that these (and other regularly variable types of stars) be searched for signs of phase modulation (in the regime of short pulse duration) and patterns, which could be indicative of intentional signalling.

Keywords:

• Cepheids
• phase modulation
• patterns
• intentional signalling

Acknowledgements

We thank many colleagues for discussions of these ideas, in particular Freeman Dyson, Ralph Becker-Szendy, Walt Simmons, and Xerxes Tata. We would like to acknowledge support by the U.S.D.O.E. under Grant DE-FG02-04ER41291 at the University of Hawaii, the N.S.F. under Grant 04-56556 at the University of California at Santa Barbara.