except you can't subtract something from infinity
it's like trying to find the square root of a negative number
Yes you can. Any operation done to infinity (with the exception of multiplication with zero) will result in infinity.
And you can find the square root of negative numbers, as long as you don't limit yourself to real numbers. (trust me, I've done nothing else than this kind of stuff for the past year :P)
Ontopic: Progress will probably come to a halt untill christmas, due to exams and stuff.