Wormholes. Computer artwork of two wormholes (white tunnels) connecting different bubble universes. These are thought to have formed in the early universe during the inflationary period of the Big Bang, the expansion of all the matter in the universe from an infinitely compact state 13.7 billion years ago. Conditions known as a false vacuum created a repulsive force that caused an incredibly rapid expansion, much faster than the ordinary expansion observed today. Since this expansion is faster than the speed of light, areas of inflation would form bubbles that would be completely isolated from each other. Wormholes are tunnels between points in space-time. They might allow travel between the bubble universes.