A paradox in itself, pigeons chase cat, but a new hypothesis suggests that two pigeons can share one pigeonhole. From Physicsworld.com:
… Jeff Tollaksen of Chapman University in California and colleagues in Israel, Italy and the UK have proposed an equally bizarre scenario dubbed the “quantum-pigeonhole effect”. The paradox begins with the observation that when you put three pigeons in two pigeonholes, there will always be at least two pigeons in the same hole. But according to the team’s quantum analysis, it is possible for none of the pigeons to share a hole.
“It’s one of those things that seem to be impossible,” says Tollaksen. But it is a direct consequence of quantum mechanics and, he adds, “It really has immense implications.”
This idea is spooky and moves us into realms only dreamt of in science fiction.
Full story at: Pardoxical Pigeons