The Universe Doesn't Allow Perfection.

I Have Experimental Evidence That Time Travel Is Not Possible.

Working With My Father [stephen Hawking ] Is A Great Thrill - He Has The Amazing Ability To Hold Enormous Amounts Of Information In His Head.

[question: What Do You Think Was The Most Important Physics Idea To Emerge This Year?] We Won't Know For A Few Years.

The Doctor Who Diagnosed Me With Als, Or Motor Neuron Disease, Told Me That It Would Kill Me In Two Or Three Years.

I Would Like Nuclear Fusion To Become A Practical Power Source. It Would Provide An Inexhaustible Supply Of Energy, Without Pollution Or Global Warming.