[mcrowder]

I'm not meaning to reopen that debate, as it "spun" out of control...

But ask your physicist friend to calculate the amount of spin needed to make the very best curveball curve such that it ends 3 feet sideways from where it would have ended had it not curved, given an initial V of 85 mph. Increase the velocity of the ball to 100 for a fastball, using the same spin.

He/she will quickly and easily be able to prove that even if a pitcher could put the same amount of backspin on a ball that a curveball pitchers puts in sidespin, 100 mph will not be enough to increase the Bernouli force enough to curve the ball upward enough to counteract gravity (which, on a 100 mph fastball, lowers the ball by about 6 feet).

However, use the same spin, and let our pitcher throw it 135 mph (actually fractions more) - the Bernouli Force curving the ball upward will now equal the gravity force curving it downward. Given the same spin, anything in excess of 135 mph will be able to curve upward more than gravity curves it downward, at least until the point that wind resistance lowers the ball's velocity to below 135 mph.

To put to rest the "impossible" faction's argument, consider a wiffleball, or even a solid plastic ball - obviously it can rise, right? Anyone remember TracBall? The white styrofoam one was easy to make rise, the yellow plastic not as easy, but still possible. The denser the object, the faster the spin must be to make it counteract gravity (even if briefly), and the faster it must be thrown.

ANY object, even a solid lead ball, if thrown with enough speed and enough spin, can curve upward to counteract gravity's force. The heavier, the more spin and speed needed.

Baseball's speed, given an equal spin to a MLB pitcher's curve ball, lands at around 135mph.

(Any nonsense about lift can be disproved easily if I have to).