Stephen Hawking Big Answers

“Is there any point in hosting a party for time travelers? Would you hope anyone would turn up?

In 2009 I held a party for time travelers in my college, Gonville and Caius in Cambridge, for a film about time travel. To ensure that only genuine time travelers came, I didn’t send out the invitation until after the party. On the day of the party, I sat in college, hoping but no one came. I was disappointed, but not surprised, because I had shown that if general relativity is correct and energy density is positive, time travel is not possible. I would have been delighted if one of my assumptions had turned out to be wrong.”

«I think we are acting with reckless indifference to our future on planet Earth. At the moment, we have nowhere else to go, but in the long run the human race shouldn’t have all its eggs in one basket, or on one planet. I just hope we can avoid dropping the basket before we learn how to escape from Earth. But we are, by nature, explorers. Motivated by curiosity. This is a uniquely human quality. It is this driven curiosity that sent explorers to prove the Earth is not flat and it is the same instinct that sends us to the stars at the speed of thought, urging us to go there in reality. And whenever we make a great new leap, such as the Moon landings, we elevate humanity, bring people and nations together, usher in new discoveries «and new technologies. To leave Earth demands a concerted global approach—everyone should join in. We need to rekindle the excitement of the early days of space travel in the 1960s. The technology is almost within our grasp. It is time to explore other solar systems. Spreading out may be the only thing that saves us from ourselves. I am convinced that humans need to leave Earth. If we stay, we risk being annihilated.»

NB: no passamento do homem que me fez interessar por estes temas. Foi Avô do meu amigo Diogo Azul e deu-me explicações de Físico-Química no oitavo ano (depois de um 2 na pauta do primeiro período).