Hello physics forum crew, I would like some help coming up with one of those "is this possible" type questions. Basically, I'm writing a sci-fi story that is has the strict limitation that all technology must be feasible within the laws of physics as we currently know them. However, there is some leeway as you can assume that man has advanced our technology for many thousands of years and might find a way to use old physics any new ways. Anyways, the question is this: can a "heat destroyer" be made? As I define it, this device takes simply converts heat into some other form of energy, either EM or perhaps electricity. Of course, this can already be done in many ways today, but what we're talking about is a matter of degree. The amount of power it generates is not important, nor is the efficiency, but the important part is it can do so "infinitely" i.e. you turn the device on and it brings itself to near absolute zero, I suppose a somewhat higher minimum cap is ok. Another limitation is, other than the heat, it can't be fed any other energy, except maybe for some control or other higher level stuff, but the key here is it's not like you have to feed this thing a huge amount of energy for it to work, it just "eats" the heat. My only lead is the carnot's work, perhaps the formula making clear that close delta T's make for very little work. But it it specifically talks about work and efficiency. I can't find a way to use the limit to definity rule out such a device. Any input is much appreciated. Thanks!