Originally posted by wolram
energy "is" energy it is inconsiquential to say if you are clever enough to extract it, if energy exists in a system then the system must be ENERGETIC therfor energy is availiable, with respect your replyies are nonsence.
if you go back to the greek, energy means "the ability to do work"
ergon is work-----energon is a kind of "inner work content" that a thing or place might have.
but in reality energy is not quite that simple because
energy can vary as to how available it is. some energy you just
cannot get at to make do work.
this can seem paradoxical to anyone who happens not to have taken a one-week course in thermodynamics (in freshman year they spend a week or so on saying why you can't get work out of heat unless you have reservoirs at two different temperatures)
Room temp is 300 kelvin (absolute is the only scale that works for this)
You can't make the heat in a room turn wheels unless you have a colder place-----like maybe outdoors is 280 kelvin, where you can put the cooling coils and dump the waste heat. If you do have a colder place, then you can run some kind of power device, some engine, on the difference.
You take in heat from the room at 300, extract some of it to turn the wheel, and dump the rest outside.
Or like, maybe the air on Mars is 230. That is very cold but it still has energy in it. However you wouldn't be able to run an engine with that energy unless you had an even colder place to put the cooling coils and dump the waste heat.
So yes the vacuum has energy in it, but how can you run an engine if there is no place colder?
that is not just a rhetorical question. maybe thermodynamics is wrong and loonies are right! anything can happen!
Maybe you can find a machine that will run on the vacuum energy. The idea causes peals of insane laughter but really
the theories we all believe do not have to be right forever.
However I personally choose to believe in thermodynamics.