If God doesn’t exist, why did the concept of his existence become almost universal? —Basanta Borah, BASEL, SWITZERLANDI don’t claim that God doesn’t exist. God is the name people give to the reason we are here. But I think that reason is the laws of physics rather than someone with whom one can have a personal relationship. An impersonal God. Does the universe end? If so, what is beyond it? —Paul Pearson, HULL, ENGLANDObservations indicate that the universe is expanding at an ever increasing rate. It will expand forever, getting emptier and darker. Although the universe doesn’t have an end, it had a beginning in the Big Bang. One might ask what is before that, but the answer is that there is nowhere before the Big Bang, just as there is nowhere south of the South Pole. Do you think our civilization will survive long enough to make the leap to deeper space? —Harvey Bethea, STONE MOUNTAIN, GA.I think we have a good chance of surviving long enough to colonize the solar system. However, there is nowhere else in the solar system as suitable as the Earth, so it is not clear if we would survive if the Earth was made unfit for habitation. To ensure our long-term survival, we need to reach the stars. That will take much longer. Let’s hope we can last until then. If you could talk to Albert Einstein, what would you say? —Ju Huang, STAMFORD, CONN.I would ask him why he didn’t believe in black holes. The field equations of his theory of relativity imply that a large star or cloud of gas would collapse in on itself and form a black hole. Einstein was aware of this but somehow managed to convince himself that something like an explosion would always occur to throw off mass and prevent the formation of a black hole. What if there was no explosion?Which scientific discovery or advance would you like to see in your lifetime? —Luca Zanzi, ALLSTON, MASS.I would like nuclear fusion to become a practical power source. It would provide an inexhaustible supply of energy, without pollution or global warming.
