Thermodynamics of Hell

You sometimes see amusing explanations using science to demonstrate that heaven is actually hotter than hell, or that hell is endothermic or exothermic.  (Don't let those words put you off reading further!)

But what about the concept of the eternal existence of hell?  Is it even a possibility that eternal torment can be maintained?

The second law of thermodynamics seems to suggest that it is not possible. It uses mathematics to describe the way that hot things cool down and that the universe will end its days uniformly cold and lifeless. 

Of course maybe hell is not in this universe but in one where our laws of physics do not operate.  And just in case you get too excited about this, bear in mind that it might take trillions of years to ensure that hell is cold enough to be comfortable.

So that leaves us with one of the usual quandaries. 

Even if hell exists in some non-physical sense, what kind of merciful god would sentence someone to torment for a mere trillion years just because of the sins that they committed during an adult lifetime of a few decades?

Would you worship a god like that?