To become a theoretical physicist ... you need to have a passionate love affair with the universe.

In physics, one of the most exciting areas is in nanotech. With computers exhausting the power of silicon, Silicon Valley could become a Rust Belt, unless we can find replacements, such as quantum computers and molecular computers. To be a leader in any field, one has to have a great imagination. Sure, we have to know the basics and fundamentals. But beyond that, we have to let our imagination soar.

Physics is often stranger than science fiction, and I think science fiction takes its cues from physics: higher dimensions, wormholes, the warping of space and time, stuff like that.

The energy necessary to create a wormhole or to wrap time into nuts is incredible. It's not for us. It's maybe for our descendants who have mastered the energy of this technology. So if one day, somebody knocks on your door and claims to be your great great great great granddaughter, don't slam the door.

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.

We're headed for what is called Type 1 Civilization, planetary civilization. Type 2 would be stellar civilization, like Star Trek. Type 3 Civilization would be galactic, like Star Wars. We are Type 0. We get our energy from dead plants, oil and coal. But the question is: Will we make it? Will we make the transition from Type 0 to Type 1? It's not clear.

Global warming is controversial, of course, but the controversy is mainly over whether human activity is driving it.