PHYSICAL EVIDENCE
Many scientists have tried to find more physical, hard evidence for the multiverse’s existence. For example, if a neighbouring universe happened to be close to ours long ago, it may have collided with our universe, creating a detectable imprint. That imprint could be in the form of distortions in the cosmic microwave background – the light left over from when the universe was a million times smaller than it is today – or in strange galaxy properties in the direction of the collision. But so far all the searches have come up empty, so the multiverse remains hypothetical.