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1. Originally Posted by King-Of-Despair
Does space have energy? It doesn't have mass at all, so it has no Kinetic Energy, and hence reaches absolute zero right? Are people saying that you can only apply temperature when/where there is mass?

*is yet to read most of ygolo's refered post which probably contains the answer*
While vacuum has no intrinsic energy, there is a small amount of electromagnetic radiation present almost uniformly throughout the universe, and I think it's something like 2 kelvin. Vacuum won't transfer it's absolute zero temperature to you...because there's nothing there. Your temperature in that vacuum is going to be determined by the amount of light energy on you at the time. Like Halla said, "sunny sides" of planets can be 200 degrees and then the dark sides are -200 degrees because there's no atmosphere to hold the sun energy.

2. Originally Posted by JocktheMotie
While vacuum has no intrinsic energy, there is a small amount of electromagnetic radiation present almost uniformly throughout the universe, and I think it's something like 2 kelvin. Vacuum won't transfer it's absolute zero temperature to you...because there's nothing there. Your temperature in that vacuum is going to be determined by the amount of light energy on you at the time. Like Halla said, "sunny sides" of planets can be 200 degrees and then the dark sides are -200 degrees because there's no atmosphere to hold the sun energy.
That makes sense, temperature is really just a classification then. Thanks Jock

3. Thermal energy is kinetic energy but on a small scale. Something with zero thermal energy essentially has not kinetic energy so would be still. (simplified but serves a theoretical purpose)

The first problem with that is relativity. There is no evidence for the existence of absolute motion, so for something to be absolutely still seems impossible/not worth speculating on past emotional reasons.

For something to be still in a particular frame of reference has it's own problem. Notably that a single particle is always absolutely still in reference to itself, so presumably something being still to just a select few frames of reference causes nothing special to happen.

Then there's the uncertainty principle. Something with zero energy would have zero momentum, if it's momentum can be measured with such certainty, it's location is infinitely unknown, meaning it exists everywhere/doesn't exist anywhere or something trippy like that. The fact that it exists in a probabilistic sense alone is already trippy enough for me.

There's a whole list of other complications regarding absolute zero. A lot of which are to do with what happens at the smallest scales ever measured, where energy and such start behaving unusually. Someone has already mentioned how energy is not required for motion, but classical temperature does align more with motion than energy, but could go either way.

4. Absolute zero only means no vibration in an atom or particle, or whotever.

If yeu bump something into it, the laws of motion and thermodynamics still apply... it would just bump into it and one would gain some vibration, the other would loose some. It's not like it's some mass plague that would wipe everything out.

Yeu're thinking grey goo, which's a totally different scenario.

5. Given it can be anywhere in the universe when you get to absolute zero, you'd have trouble not bumping it into stuff on the way.

6. What happens at absolute zero? - physics-math - 17 February 2010 - New Scientist

New Scientist article on it, easy to read and not a terrible summary.

7. I found this thread kind of interesting, well certain responses anyway.

I think it is best just to consider Absolute Zero to be a mathematical place-holder, rather than a real physical state.

Originally Posted by Katsuni
Absolute zero only means no vibration in an atom or particle, or whotever.
Which seems impossible to me - matter without inherent angular momentum?

Actually, even approaching zero, things get somewhat strange. I wish I understood it better.
http://en.wikipedia.org/wiki/Bose-einstein_condensate

8. If you can imagine it, its possible. alot of things are beyound are capabliities, including ability see right now.

9. Why can't you just grab a particle and stop it from moving?

10. Because in order to see it, you have to interact with it, with makes it "move."

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