I think a colony in space will take much longer than sci fiction writers think. It costs $10,000 to put a pound of anything into near earth orbit. That is your weight in gold. It costs about $100,000 a pound to put you on the moon. And it costs $1,000,000 a pound to put you on Mars.

A hydrogen bomb, for me, was puny compared to the Big Bang - the creation of the universe. That's what I really wanted to work on - the nature of the universe itself, and that's what I do for a living.

We should explore new ways to drive down the cost of space travel. instead of costly booster rockets, maybe we should think of laser/microwave driven rockets, or space elevators. Until then, the cost of space exploration will limit our ability to explore the universe.

Language and emotions are too easily misread. For example, laughing can mean many things: laughing with you or at you. Does that laugh reflect joy, anger, or that s/he's about to fire you? Too many jobs require complex feelings, pattern recognition, common sense, and the human touch.

I'm not a science fiction writer, I'm a physicist. These are scientists who are making the future in their laboratories.

We are slowly isolating the genes involved with the aging process. We do not have the fountain of youth, but I think, in the coming decades, we will unravel the aging process at the genetic level.

"Did God have a mother?" Children, when told that God made the heavens and the earth, innocently ask whether God had a mother. This deceptively simple question has stumped the elders of the church and embarrassed the finest theologians, precipitating some of the thorniest theological debates over the centuries. All the great religions have elaborate mythologies surrounding the divine act of Creation, but none of them adequately confronts the logical paradoxes inherent in the question that even children ask.