Ernest Lawrence
It's the theoretical physicists - Albert Einstein, Robert Oppenheimer, Stephen Hawking - that get all the praise and adulation - at least amongst the general population
Of course, some people have to do the actual work. And if you consider 70 hours a week wrestling with huge bulky apparatus doing work, then Ernest Orlando Lawrence certainly did at some work.
In any case, it was Ernest who moved science from Science to Big Science. That, of course, means Expensive Science. On the other hand, without Big - and Expensive - Science - you wouldn't be sending messages to your friends in Hamburg, Germany faster than to your mother in East Orange.
So if you want to learn a bit more about the Importance of (Being) Ernest - just click here.