As Heinz Pagels has said, The challenge to our civilization which has come from our knowledge of the cosmic energies that fuels the stars, the movement of light and electrons through matter, the intricate molecular order which is the biological basis of life, must be met by the creation of a moral and political order which will accommodate these forces or we shall be destroyed. It will try our deepest resources of reason and compassion.

Some advice: keep the flame of curiosity and wonderment alive, even when studying for boring exams. That is the well from which we scientists draw our nourishment and energy. And also, learn the math. Math is the language of nature, so we have to learn this language.

A soul might very well exist, but we, as physicists, try to measure and quantify everything. So far, no one has been able to create an experiment to do this for the soul. Efforts have been made to weigh the body after death, but each time we find no evidence of a soul. So a soul may very well exist, but it is not a testable theory.

To understand the difficulty of predicting the next 100 years, we have to appreciate the difficulty that the people of 1900 had in predicting the world of 2000.

So often, science fiction helps to get young people interested in science. That's why I don't mind talking about science fiction. It has a real role to play: to seize the imagination.

Today's clunky smart glasses will be replaced by smart contact lenses. We'll command them by voice, blinking, or even thinking, to interact visually in 3-D with the Internet.

Once confined to fantasy and science fiction, time travel is now simply an engineering problem.