Davy Stump asked:
What would a substance at absolute zero look like?
Dave - I see no particular reason why it would look any different to how it would appear at any other temperature (below melting point). If its staying at absolute zero, especially if you can look at it and you’re shining light on it, then it’s not absorbing very much energy, because as soon as you shine some light on it, and if any of the light was absorbed, then its going to get hotter than absolute zero. But I’ve seen very, very cold substances down to sort of minus 270-odd and they look pretty much like other substances.
Chris - Wouldn’t the pure act of looking at them, visualizing them, wouldn’t that put some energy and so it couldn’t be at absolute zero anyway?
Dave - Yes. Essentially, if you’re shining light on them, you’re going to give them energy and you’re going to heat them up. And that said, it could be transparent, so the only one thing you could look at and keep at absolute zero will be transparent but it’s not to say that all things at absolute zero are transparent. Not that you can ever get there!
Davy Stump asked the Naked Scientists: While watching a show on space, I had a question. What would an object taken to Absolute Zero (0° K) look like? Would it be black, shiny, white, or what? Thank you, David Stump What do you think? Davy Stump , Thu, 27th Aug 2009
it depends on if light gives things it hits energy. i think it must. but that means it's no longer at absolute zero. so we couldn't actually observe things at absolute zero. i am not sure about this, though.
I don't think you can talk in terms of 0K but, at a very low temperature, there doesn't seem any reason why the surface charges couldn't be moved. That would produce reflection, if the energy gap was appropriate.. lyner, Thu, 27th Aug 2009
At a zero temperature all emanations will stop. As we only can define subatomic particles by probability and those are what makes what we call matter we better look at a subatomic particle first.
You can't get to 0K but you can get arbitrarilly close.
It is a interesting question BC.
Which part of "You can't get to 0K" didn't you understand?
You cannot observe it because it cannot exist, and if it did the light needed to see it's colour would give it energy so it wouldn't be 0K anymore.
I'm betting 0K would turn the universe to scrambled eggs, which might explain why the closer we get to absolute zero the harder it is to get there. ...lets split up..., Fri, 4th Dec 2009
I prefer my scrambled eggs hot anyway !! neilep, Fri, 4th Dec 2009
What is there to discuss?
if your talking about getting to "absolute zero" then, no, its not possible. we have attained -273 Celsius or -459.4 Fahrenheit. which is pretty close to -273.15 Celsius/-459.67 Fahrenheit (the supposed number of absolute zero). but it is impossible to remove all the heat from an object. something colder must exist to transfer the heat to, but since absolute zero is as cold as it gets it is unattainable. ..., Wed, 10th Feb 2010