Contrary to some's (i.e., mine) beliefs, the baseball world did not pause these last two weeks while I went on vacation and navigated a move. It's a shocking thing to learn that one is not the center of the universe. That said, you can expect a few quick looks at some interesting goings-on from the last two weeks over the next couple of days. The first is a piece of brilliance making its way around the internet this morning from the genius minds of xkcd (who you might remember from "The Problem with Sabermetricians")…
Randall Munroe, the artist behind xkcd, applied his mathematical mind to the one question we've all wondered: What would happen if you tried to hit a baseball pitched at 90% the speed of light?

As you might imagine, the answer to the question is something much more fascinating than "It arrives in the catcher's mitt really, really fast":
The constant fusion at the front of the ball pushes back on it, slowing it down, as if the ball were a rocket flying tail-first while firing its engines. Unfortunately, the ball is going so fast that even the tremendous force from this ongoing thermonuclear explosion barely slows it down at all. It does, however, start to eat away at the surface, blasting tiny particulate fragments of the ball in all directions. These fragments are going so fast that when they hit air molecules, they trigger two or three more rounds of fusion.
After about 70 nanoseconds the ball arrives at home plate. The batter hasn't even seen the pitcher let go of the ball, since the light carrying that information arrives at about the same time the ball does. Collisions with the air have eaten the ball away almost completely, and it is now a bullet-shaped cloud of expanding plasma (mainly carbon, oxygen, hydrogen, and nitrogen) ramming into the air and triggering more fusion as it goes. The shell of x-rays hits the batter first, and a handful of nanoseconds later the debris cloud hits.

It goes on from there and is worth a read, even if you don't like math. Some really outlandish things happen at the extremes of physics which would make a baseball game quite interesting. The rule 6.08(b) interpretation is a nice touch.
For those who did read it (and are scientifically-minded), I have a question. All of the effects that Randall describes in his scenario seem to be based on the ball colliding with air molecules. What would happen if this "fastball" were tossed in a vacuum? Would we finally be able to see the near-lightspeed baseball game we've all been dreaming about since we were kids? If so, I know one person who might have a leg-up over the rest of us: Satoshi Furukawa.
Thank you for reading
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By the way, if the hitter could swing at a relativistic speed too, a further by-product would be the promotion of a certain Mariners prospect still in rookie ball.
Now I wish I could throw you another hypothetical... like what would happen if the batter could swing the bat at exactly the same speed the ball was traveling, in a vacuum? Would the fusion still take place, or would the matching momentums change it somehow? What if the bat touched the ball for only a split second?
Sorry. I just like throwing out hypotheticals.
Classic.