The river of time may fork into rivers, in which case you have a parallel reality and so then you can become a time traveler and not have to worry about causing a time paradox.

In the 1950s, we had all these B-grade science-fiction movies. The point was to scare the public and get them to buy popcorn. No attempt was made to create movies that were somewhat inherent to the truth.

I think Newton would be the greatest scientist who ever lived.

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

The media, of course, loves to make claims about the fountain of youth. Don't believe it. No one has it. But we're getting close.

I agree, along with Carl Sagan, that we should eventually become a two planet species. Life is too precious to place on a single planet.

The best theory comes from string theory, which states that dark matter is nothing but a higher vibration of the string. We are, in some sense, the lowest octave of a vibrating string.