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Detecting Signals. SETI scientists are sometimes criticized for using “old technology” in their search for signals. Perhaps extraterrestrials have moved beyond radio and light signaling and are using something much more sophisticated. Discuss (a) the advantages of radio and light for interstellar communication and (b) any reasonable alternatives you can think of. There is always the possibility that “new physics” will provide faster or more efficient methods for signaling. Do you think this is a reason to limit current SETI efforts?
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