[QUOTE=retina;460026]Hmm, degassing a vacuum. An interesting idea.[/QUOTE]

But of course. Vacuums suck. In fact, they suck in so much air in that they would float away like balloons unless you degass them periodically.

That's why strong speaker magnates hate them: their one weird trick is that they suck up all the hot air the magnates emit. As they say, power abhors a vacuum.

[QUOTE=GP2;460028]But of course. Vacuums suck. In fact, they suck in so much air in that they would float away like balloons unless you degass them periodically.[/QUOTE]Curious. I would have thought vacuums were already in the lightest possible state. Show how much I know.

[QUOTE=GP2;460028]But of course. Vacuums suck. In fact, they suck in so much air in that they would float away like balloons unless you degass them periodically.[/QUOTE]

I very much appreciate the humour. But technically vacuums don't suck, they produce a pressure differential. They produce a low-pressure space which the ambient pressure fills.

It's much like a refrigerator or a freezer. It is impossible to create cold; all you can do is move heat.

[QUOTE=chalsall;460076]It is impossible to create cold ...[/QUOTE]Mr [url=https://en.wikipedia.org/wiki/Boyle%27s_law]Boyle[/url] might want to have a word with you.

[QUOTE=retina;460077]Mr [url=https://en.wikipedia.org/wiki/Boyle%27s_law]Boyle[/url] might want to have a word with you.[/QUOTE]

And the [URL="https://en.wikipedia.org/wiki/Second_law_of_thermodynamics"]Second law of thermodynamics[/URL] might want to have a word with you. :smile:

[QUOTE=chalsall;460078]And the [URL="https://en.wikipedia.org/wiki/Second_law_of_thermodynamics"]Second law of thermodynamics[/URL] might want to have a word with you. :smile:[/QUOTE]

TBH, it is easy to create cold (just thik to your fridge). What's really hard is to do it efficiently.

[QUOTE=retina;460029]Curious. I would have thought [strike]vacuums[/strike] [b]vacua[/b] were already in the lightest possible state. Show how much I know.[/QUOTE]FTFY. HTH. HAND.

[QUOTE=ET_;460079]TBH, it is easy to create cold (just thik to your fridge). What's really hard is to do it efficiently.[/QUOTE]

With all due respect, your fridge is not creating cold. It is moving heat from the inside of the compartment to the outside (most likely to the back or the bottom). The warm air then needs to be sent outside.

If you don't believe me, open your fridge door and let it run for 24 hours in an enclosed space. Trust me that not only will all your food be ruined, but your space will be warmer.

It saddens me a little bit how little most people understand basic physics.

[QUOTE=chalsall;460084]With all due respect, your fridge is not creating cold. It is moving heat from the inside of the compartment to the outside (most likely to the back or the bottom). The warm air then needs to be sent outside.

If you don't believe me, open your fridge door and let it run for 24 hours in an enclosed space. Trust me that not only will all your food be ruined, but your space will be warmer.

It saddens me a little bit how little most people understand basic physics.[/QUOTE]

Moving heat away is not creating cold, in your words.
Fine.
How do you call the action of temperature lowering, if not "creating cold"?
Maybe I have a linguistic issue here... :smile:

BTW, I am less than a nerd in Physics, but the second law of Thermodynamics talk about [I]isolated systems[/I], something we were not dealing about here.

[QUOTE=ET_;460085]How do you call the action of temperature lowering, if not "creating cold"? Maybe I have a linguistic issue here... :smile:.[/QUOTE]

It's known as "doing work". Yes, you can create temperatures lower than ambient, but it requires energy to do so. Edit: Said spent energy results in greater entropy, which must be sent somewhere.

[QUOTE=ET_;460085]BTW, I am less than a nerd in Physics, but the second law of Thermodynamics talk about [I]isolated systems[/I], something we were not dealing about here.[/QUOTE]

At the end of the day, we are. The Universe is a closed system.

Even the rotational momentum should equal zero.

[QUOTE=chalsall;460089][QUOTE=ET_;460085]BTW, I am less than a nerd in Physics, but the second law of Thermodynamics talk about [I]isolated systems[/I], something we were not dealing about here.[/QUOTE]

At the end of the day, we are. The Universe is a closed system.[/QUOTE]

I don't think so, at least not in the sense that energy is conserved,
[url]http://www.preposterousuniverse.com/blog/2010/02/22/energy-is-not-conserved/[/url]
unless you take the point of view that the expansion of the universe does negative work
[url]https://medium.com/starts-with-a-bang/is-energy-conserved-in-a-universe-with-dark-energy-a26572cc6853[/url]