Yakov Lvovich Alpert (Russian: Яков Львович Альперт; March 1, 1911 – October 5, 2010) was a Russian-born American physicist whose principal field of research was space plasma physics.

In 1928 he obtained an excellent grade in the entrance examination for the Ukrainian Polytechnic Institute, but because his father, a commercial traveler, was considered not to be a worker, he was refused admission; instead, he took employment as a carpenter.

He was able to get a job as a technician at the Radio Institute of the Ministry of Communications in 1931, and from that time he remained in his chosen field of physics.

It was organized by Victor Brailovsky, and the other participants included Alexander Lerner, Yuri Orlov, and Anatoly Sharansky; though not himself a candidate for emigration, Andrei Sakharov often attended the seminar and supported the refuseniks until his exile to Gorky in 1980.

Alpert's main scientific interests at the FIAN and the IZMIRAN were Between 1936 and 2001, he had 8 books published in Russian and 11 in English (9 original monographs, 3 second editions), the last one being his autobiography.