Trillions of years into the future, when all stars are gone...all parts of the cosmos will cool to the same temperature as the ever-cooling background. At that time, space travel will no longer provide refuge because even Hell will have frozen over. We may then declare that the universe has died-not with a bang, but with a whimper.

Some memories are best absorbed through your eyes in real time, even if you have no record of it later. Because then you can access that memory and how you felt in that moment. If you're looking at your cellphone screen, taking a video of something that is otherwise unforgettable, watching it later will not recover the emotion you would have had, had you witnessed it directly.

I want to encourage people to not think in terms of gifts, but think in terms of, wow. You work hard to succeed at that, because that's exactly what I do.

Even with all our technology and the inventions that make modern life so much easier than it once was, it takes just one big natural disaster to wipe all that away and remind us that, here on Earth, we're still at the mercy of nature.

Italy valued cathedrals while Spain valued explorers. So worldwide, five times as many people speak Spanish than Italian.

God displayed a sense of humor when he configured the region between our legs an entertainment complex built around a sewage system.

There are street artists. Street musicians. Street actors. But there are no street physicists. A little known secret is that a physicist is one of the most employable people in the marketplace - a physicist is a trained problem solver.