Short stories by Larry Niven
Listing 3 stories.
In a universe where time travel has become the norm, an inexplicable suicide epidemic afflicts the people who successfully ventured to the past, leaving a grisly detective with a confounding mystery to solve.
A couple of Angelenos realize in the middle of the night that the world is ending, decide to enjoy their last night together.
After being sentenced to death row, a man must seek help from his cellmates