Photons emerging from a wormhole, illustration, Theorists postulate that photons could pass through a black hole into a structure known as a wormhole, and come out the other side. This hypothetical method of travel would shorten a journey that would take years even if travelling at or near the speed of light. The concept of curved spacetime, and using wormholes to travel to distant parts of the universe, follow from Einstein's General Theory of Relativity.