Physics ruins everything
Let's list some things ruined by physics.
All dogs go to heaven, but heaven is finitely large and the number of dogs that will ever die has no hard limit. Which means eventually heaven will become massive enough to collapse into a black hole.
heaven is finitely large
Is it though? Or is it just the number of people who go there finite?
Few religions are definite about the size of Heaven, but on the planet Earth the Book of Revelation (ch. XXI, v.16) gives it as a cube 12,000 furlongs on a side. This is somewhat less than 500,000,000,000,000,000,000 cubic feet. Even allowing that the Heavenly Host and other essential services take up at least two thirds of this space, this leaves about one million cubic feet of space for each human occupant- assuming that every creature that could be called ‘human’ is allowed in, and the the human race eventually totals a thousand times the numbers of humans alive up until now. This is such a generous amount of space that it suggests that room has also been provided for some alien races or - a happy thought - that pets are allowed.
Terry Pratchett, the Last Hero
And then on the other hand, there's hell.
By the ideal gas laws, the temperature and pressure of a container vary both based on the amount of mass contained within a unit of volume. In order to reason about it, then, one must assume that souls contain some mass, and that some number of souls are being consigned to hell at some rate. (Given the number of religions that comprise a minority of the world's population but teach that everyone else is going to hell, point #2 can be taken for granted. Let us assume point #1 is also accurate, for the purposes of this discussion.)
Therefore, hell is slowly, steadily being filled with souls. The only remaining question, then, is whether or not hell is expanding, and if so, is it expanding at a rate proportionate to the influx of souls, or faster, or slower?
If it is expanding faster, then the temperature inside will continue to drop until hell freezes over. If slower or not at all, on the other hand, the pressure inside will continue to build until all hell breaks loose!
All dogs go to heaven, but heaven is finitely large and the number of dogs that will ever die has no hard limit.
Physics says no.
ZOMG! PHYSICS RUINED THE OP!