For the famous British theoretical physicist Professor Stephen Hawking, alien life was real and warned us not to make contact. According to Professor Hawking, human contact with aliens would bring doom to the human race living on Earth. Hawking began expressing his concern about how aliens could destroy the human race in 2010. According to Hawking, in a universe with 100 billion galaxies, with each containing hundreds of millions of stars, it was unlikely that Earth was the only place where intelligent life had evolved. He had rationalized that there was a high probability that several species of intelligent life, many of which were more advanced than us, existed somewhere other than Earth.

His reasoning was that, mathematically, given the vast number of galaxies, the probability of the existence of aliens was perfectly rational.

Professor Hawking believed that humanity would be shocked by a contact with aliens. Hawking postulated that it was possible that some of the aliens might have depleted all their resources, and were looking for resource-rich planets to subjugate in order to supply their needs, thus making contact with them very dangerous. He also suggested that alien life could exist in many parts of the universe, not just in the Milky Way, many of which were in search of resources. He imagined that they might exist in massive ships, becoming nomads, looking to plunder whatever planets they could reach. He compared alien contact to the contact made by Europeans with the people of the New World, with an outcome similar to when Christopher Columbus first landed in America, which didn't turn out very well for the indigenous cultures.

Professor Stephen Hawking served as the director of research at the Centre for Theoretical Cosmology within the University of Cambridge. His scientific works included collaboration with Roger Penrose on gravitational singularity theorems in the framework of general relativity, and the theoretical prediction that black holes emit radiation, commonly referred to as Hawking radiation. Hawking was the first to set forth a theory of cosmology explained by a union of the general theory of relativity and quantum mechanics. He was a vigorous supporter of the interpretation that the effects of gravitational waves on space and time caused them to be distorted.