Let's be clear. I didn't state that the laws of physics might change, just our understanding and knowledge of them. It's entirely possible that there is something we don't know about the nature of this that makes it possible. There have been theories that were declared true in the past that have been proven not so universally true. This is not a 2+2, A is A situation. There are plenty of options and things that can be done to deal with generated heat, just because today's level of technology is so inefficient that it puts out a LOT of heat really fast doesn't mean things will always be this way... as evidenced by the fact that I have a calculator that can do more calculations faster than supercomputers of the 1970s. Those would cook a person, my calculator will not generate enough heat to do this before you have much bigger concerns like food, air and water.
But more efficiency is not 100 percent efficiency. What you were talking about before was perpetual motion, the generation of energy with
zero cumulative loss. That's not just difficult, that's simply impossible. Entropy is absolutely fundamental to the universe as we know it. Everyone who knows anything about physics knows that perpetual motion is not just an engineering problem but a fundamental absurdity that can never be achieved.
If you were only saying that power systems could be made efficient enough that heat buildup would be reduced and a cloak could function for, say, a few hours with, say, an energy output only marginally above local background radiation, that's something I can accept. But you seemed to be saying it would be possible for
all waste energy to be recovered, and that's when you cross the line from plausible futurism to pure Did Not Do the Research.
Yes, there are things we don't know yet about how physics works, but it's wrong to assume that means that any given physical law can be thrown out altogether. New understandings
add to our knowledge, but the things we knew before still remain valid. Newton's laws were only an approximation of Einstein's laws, but everything they say is still entirely true within the range of conditions in which they were defined. If something is proven to be true, then new knowledge won't suddenly make it untrue.
Then there is of course a matter of simply MASKING the heat rather than actually holding it in. Who says the heat's not still there, it's just not detectable by the other ship's sensors? Why does a cloak necessarily HAVE to hold it all in? It could still be radiating into space but the cloaking technology somehow affects sensors such that they can't detect it, it's like saying a cloaking device is actually making the ship actually vanish, when we know that's not the case. Makes sense since cloaking and sensor technology within Trek has been in a race since the beginning.
Okay, if a cloaking device is merely a way of hacking the enemy's sensors, that's actually credible. Pure electronic countermeasures, nothing implausible about that. But if the enemy knew that were how it worked, then surely they'd use a range of different sensor techniques and would run them on isolated, shielded computer systems so they couldn't all be hacked simultaneously or at all by external signals. Or they could use sensors that don't have any computer components at all between the detector and a purely mechanical readout device. For instance, use a film camera with a type of film that's chemically receptive to infrared light. How do you "jam" a piece of film?
The bottom line is, while there are limited options for stealth in space, there is no literal, perfect invisibility. There will always be
some emissions given off by any ship, and therefore there will always be the theoretical possibility of detection.