There may be many Big Bangs that happened at various and far-flung locations, each creating its own swelling, spatial expanse, each creating a universe - our universe being the result of only one of those Big Bangs.

The pinpoints of starlight we see with the naked eye are photons that have been streaming toward us for a few years or a few thousand.

The number of e-mails and letters that I get from choreographers, from sculptors, from composers who are being inspired by science is huge.

To tell you the truth, I've never met anybody who can envision more than three dimensions. There are some who claim they can, and maybe they can; it's hard to say.

...things are the way they are in our universe because if they weren't, we wouldn't be here to notice.

My best teachers were not the ones who knew all the answers, but those who were deeply excited by questions they couldn't answer.

I was holding [my four-year-old daughter] and I said, 'Sophia, I love you more than anything in the universe.' And she turned to me and said, 'Daddy, universe or multiverse?'