Red mercury is a discredited substance, most likely a hoax perpetrated by con artists who sought to take advantage of gullible buyers on the black market for arms. These con artists described it as a substance used in the creation of nuclear weapons; because of the secrecy surrounding nuclear weapons development, it is difficult to disprove their claims completely. However, all samples of alleged "red mercury" analyzed in the public literature have proven to be well-known, common substances of no interest to weapons makers.

Samuel Theodore Cohen was an American physicist who is generally credited as the father of the neutron bomb.