A tachyonic [tak-ee-on-ik] antitelephone is a hypothetical device in theoretical physics that could be used to send signals into one’s own past. Albert Einstein in 1907 presented a thought experiment of how faster-than-light signals can lead to a paradox of causality, which was described by Einstein and Arnold Sommerfeld in 1910 as a means ‘to telegraph into the past.’ The same thought experiment was described by physicist Richard Chace Tolman in 1917; thus, it is also known as Tolman’s paradox.
A device capable of ‘telegraphing into the past’ was later also called a ‘tachyonic antitelephone’ by science fiction writer and astrophysicist Gregory Benford. According to current understanding of physics, no such faster-than-light transfer of information is actually possible.
read more »
The Daily Omnivore 