exotic matter

Wormholes: theoretical tunnels through spacetime. Einstein-Rosen bridges, exotic matter, traversability, ER=EPR, and time travel paradoxes explained.

A wormhole — a shortcut through spacetime connecting two distant points — would revolutionize physics, transportation, and our place in the universe. But the physics suggests it would also be unstable, possibly lethal, and almost certainly a one-way trip.