So what is ? It's energy in the form of moving particles or waves, emitted by an atom or another body as it changes from one energy state to another.… - Suzie Sheehy

Suddenly, nothing else mattered. I wanted to know... about gravity and particles and and relativity. About stars and atoms and light and energy. Above all, I wanted to know how it was all connected and how I was connected to it. ...[I]t mattered to me as a human ...if I managed it even a little bit, I'd not have wasted this little blip of time as a conscious being. I decided to become a physicist.

[S]ometimes some of our craziest ideas, and I've been through some pretty crazy ideas of things that you could do with a particle accelerator here... [S]ometimes they turn out to be surprisingly good ones if you do them in the right way, and these machines are not just useful for particle physics. They're useful for all sorts of other things like cancer treatment, like killing bacteria in food, and other things I haven't discussed like carbon dating, and imaging down to the atomic scale, and all sorts of other things...

So you can actually put your head in the beam of an accelerator and survive it. And he's not the only one to have done it.