Paul Horowitz (born 1942) is an American physicist and electrical engineer, known primarily for his work in electronics design, as well as for his role in the search for extraterrestrial intelligence (see SETI).

His interest in practical electronics has led to a handful of inventions, including an automated voting machine and an acoustic mechanism for landmine detection, and an electronic Morse Code/Baudot code keyboard using a diode matrix and 66 TTL integrated circuits for Amateur Radio use.

Harvard biologist Ernst Mayr has sharply criticized Horowitz for wasting the resources of the university and the efforts of graduate students on such an endeavour.

Carl Sagan provided a strong rebuttal to Mayr's criticism,[2] and pointed out that many eminent biologists and biochemists had endorsed SETI with the statement: We are unanimous in our conviction that the only significant test of the existence of extraterrestrial intelligence is an experimental one.

Horowitz and Sagan reported that, in the course of project META, they had detected 37 signals "which survived all our cuts" and cannot be positively identified.