The Big Rip, conceptual computer illustration. The Big Rip is a theory of the end of the universe. The theory is that if the 'dark energy' that drives the expansion of the universe has a certain value, then the expansion of the fabric of the universe expands at an ever-increasing rate. This would eventually lead to first galaxies being torn apart (left), then structures such as nebulae (centre), then planets such as Earth (upper right), and eventually atoms and subatomic particles themselves. If the theory is correct, the universe will end in around 20 billion years.