Less than 0 kelvin? Meaning of temperature

Ki Man

due to the definition of temperature, its impossible to have negative movement, so by soemhow going below 0 Kelvin would actually be going warmer

JPRitchie

Zero point motion is predicted to persist to 0K. This energy cannot be radiated or lost any other way because there are no lower vibrational states available. But, the remaining motion occurs on a scale that is relatively small with respect to atomic sizes. The time-averaged atomic position remains fixed. The Lewis and Randall definition of 0K is that the entropy also be 0 and the substance be in a pure, perfect, crystalline state. As you get close to 0K, unpaired electron spin or nuclear spin can complicate matters, because mixtures of spin states can be obtained in the absence of a perturbing applied field.
-Jim

.ultimate

If you say all the EM radiations carry energy. How can the energy 'dissapper'? Isnt that violation of Enery-Mass equivalence


All matter is supposed to be made of same material. And What do you mean by 'nature' in atomic terms.


Well, this is purely hypothetical. X-rays are not absorbed by skin neither by bones. I recently postulated the reason for reflection of light

Size of wavelength of Visible radiation = of order of [tex]10^{-7}[/tex]
and size of whole atom = [tex]10^{-10}[/tex]
Size of nucleas = [tex]10^{-15}[/tex]
Empty space = [tex]10^(-5}[/tex]

Hence the EM wave will not penetrate through the atom, and the photon will be reflected as such.

You can apply tjhis to the above scenario, X-rays can penetrate through the skin cells but not bonemarrow.



Fine that Heat is considered to be molecular Kinetic Energy, But how can it be 'lost' as radiations?

Zzzz. (sleeping)

ZapperZ

Read again what I said. I said the "light disappear". The FACT that I then said that it has been turned into heat means that the energy in that light has been converted in another form of energy, which is heat.

Then you must have not read the FAQ that I have written and asked you to read. Consider the following: Graphite and Diamond are both made up of carbon atoms. Yet, they can't be any more dissimilar. That alone is enough to show you why what you wrote isn't complete.

Careful with your speculative post and re-read the PF guidelines that you have agreed to.

Furthermore, you missed the point. I was debunking your idea that the higher the energy of em radiation, the most that energy will be absorbed. X-ray has a higher energy per photon than visible light, yet it isn't absorbed by skins the way visible light is.

Eh? Please read the FAQ!

This is getting convoluted. I suggest you understand one part at a time before delving into another, and certainly before asking about "negative temperatures".

Zz.

throng

Just a thought. - space is a positive energy form +Ey plus a negitive energy form -Ey (y being qty) thus expressed Ey-Ey. It's not the some as zero. Conceptually it's different.

Quantum geeks have done experiments to support this "negative energy" or "antimatter" (same thing by definition) and concluded it is actually "positive energy" (matter)

If energy can't be created or destroyed and doesn't have geometric origins (time and place) It follows that it can exist independently of space and time. Defying any absolute zero of time space or temperature.

My muse is,

Is this "positive" energy outside added to equal "positive" energy inside (our universe) a possible explanation for why Vacuum has no temperature as opposed to 0 temperature?

xavier_r

Yes, I think the same...

pally

I suggest you go learn some maths first too, how can the empty space inside an atom be greater that the size of the atom itself?....

anyway...

from what I've read about this...
as a system approaches zero kelvin, the atoms rearrange themselves to form a perfectly crystalline structure, however due to the spin of nuclei this alternte incidences occur in structure, in which there are certain outcomes.
negative energy doesn't exist in boundless energy systems, only those with two energy states or less, where by having increased the energy so much the system can have no more, and therefore adding energy removes energy from the system.