When you drive your car, E = mc2 is at work. As the engine burns gasoline to produce energy in the form of motion, it does so by converting some of the gasoline's mass into energy, in accord with Einstein's formula.

Understanding requires insight. Insight must be anchored.

Einstein comes along and says, space and time can warp and curve, that's what gravity is. Now string theory comes along and says, yes, gravity, quantum mechanics, electromagnetism - all together in one package, but only if the universe has more dimensions than the ones that we see.

Science is the greatest of all adventure stories, one that's been unfolding for thousands of years as we have sought to understand ourselves and our surroundings.

...quantum mechanics—the physics of our world—requires that you hold such pedestrian complaints in abeyance.

I can assure you that no string theorist would be interested in working on string theory if it were somehow permanently beyond testability. That would no longer be doing science.

So many galaxies, so many planets out there in the universe circling so many stars... it just feels like there's a very good chance that there is another Earth-like planet out there that is able to support some kind of life similar to what we're familiar with.