"Extempore" (alternate title "The Beach Where Time Began") is a science fiction short story by American writer Damon Knight.
It first appeared in the August 1956 issue of Infinity Science Fiction and has been reprinted twice, in Far Out (1961) and The Best of Damon Knight (1976).
[1] Albert Rossi, a New York dishwasher, learns to travel through time.
By an effort of will he manages to stop at a "scarlet beach with its golden laughing people".
But he is now frozen in time forever and appears to the beachcombers as a rock-hard, immobile statue.