But if there is a God, you go to heaven and live for eternity in bliss (of which we will assume to have a value of infinity ∞).
LOL. Nice try but I see what you did thar.
Try this proof again with statistical assumptions that make more sense and you will get results that you would not agree with:
Total number of possible beliefs about death and the afterlife = N
P(A) = Probability that god and heaven exists as christians believe = 1 / N
Thus the probability that god and heaven exists as christians believe is NOT true = 1 - P(A) = (N-1)/N
Assuming there is no limit (infinite) to the number of beliefs about the after life and each belief is equally likely to occur, then probability that you would die and go to heaven as christians believe would be P(A) = lim 1/x (as x->inifinity) = 0. The probability that this is false is 1 - P(A) = lim(x-1)/x (as x->infinity) = 1. So if you are looking at this probabilistically, christians, or any other single religion with a specific belief about the death and after life is %100 likely to be wrong as long as there is an infinite number of different possible beliefs.