I've used some What If? questions before as subjects to natter about, but I had never gone all the way back to the first edition of the page in 2012. It seems relevant as we approach the beginning of baseball season.
A questioner wonders what would happen if you tried to hit a baseball thrown at 90% of the speed of light. The short answer is that you wouldn't -- if the ball could somehow be accelerated to that speed within an atmosphere its collision with the atoms of air in front of it would create a massive release of energy that would be the next best thing to an atom bomb going off.
And if it happened in Yankee Stadium during a Yankees-Dodgers series, well, it might just turn into the best thing period.