# What happens to the electrons at absolute zero? **URL:** \ **Category:** Factual Questions\ **Created:** [December 18, 2002, 11:15pm UTC](https://boards.straightdope.com/t/what-happens-to-the-electrons-at-absolute-zero/143679 "2002-12-18T23:15:42Z")\ **Posts on this page:** 18\ **Page:** 1
**Author:** ![Alietta](https://avatars.discourse-cdn.com/v4/letter/a/ecb155/32.png) [@Alietta](https://boards.straightdope.com/u/Alietta)\ **Post date:** [December 18, 2002, 11:15pm UTC](https://boards.straightdope.com/t/what-happens-to-the-electrons-at-absolute-zero/143679/1 "2002-12-18T23:15:42Z")
If the electrons compeltey stop at K = 0 then where do they go? Are they frozen in space? Do they fall to the ground? My chemistry teacher could not explain this. ---
**Author:** ![MC\_Master\_of\_Ceremonies](https://avatars.discourse-cdn.com/v4/letter/m/bb73d2/32.png) [@MC\_Master\_of\_Ceremonies](https://boards.straightdope.com/u/MC_Master_of_Ceremonies)\ **Post date:** [December 18, 2002, 11:29pm UTC](https://boards.straightdope.com/t/what-happens-to-the-electrons-at-absolute-zero/143679/2 "2002-12-18T23:29:54Z")
Well, electrons at absolute zero must have no kinetic energy, so they would not move at all (if the were being acted upon by gravity then gravitational p.e. would convert to k.e., raising their temps) But of course absolute zero isn’t obtainable as it violates the third law of thermodynamics and not to mention the fact that too-well defined temps cannot exist in quantum physics. ---
**Author:** ![TheBrahmanator](https://avatars.discourse-cdn.com/v4/letter/t/9de0a6/32.png) [@TheBrahmanator](https://boards.straightdope.com/u/TheBrahmanator)\ **Post date:** [December 18, 2002, 11:32pm UTC](https://boards.straightdope.com/t/what-happens-to-the-electrons-at-absolute-zero/143679/3 "2002-12-18T23:32:04Z")
Wait till he explains quantum chemistry… The electrons effectively exist in fields of probability called orbitals, not really a given point in space, as weird as that sounds. Heat isn’t reflected in the motion of the electrons, but the movements of the atoms and molecules taken as complete units. As far as I know, the electron continues in its orbital while the entire atom taken as a whole has stopped moving. ---
**Author:** ![MC\_Master\_of\_Ceremonies](https://avatars.discourse-cdn.com/v4/letter/m/bb73d2/32.png) [@MC\_Master\_of\_Ceremonies](https://boards.straightdope.com/u/MC_Master_of_Ceremonies)\ **Post date:** [December 18, 2002, 11:38pm UTC](https://boards.straightdope.com/t/what-happens-to-the-electrons-at-absolute-zero/143679/4 "2002-12-18T23:38:13Z")
as an addition to my first post: Frozen is the wrong word though, as it implies an absolute postion. I’m not sure if your correct Brahamantor, because electric fields are impossible at absolute zero 😕 ---
**Author:** ![SandyHook](https://avatars.discourse-cdn.com/v4/letter/s/dec6dc/32.png) [@SandyHook](https://boards.straightdope.com/u/SandyHook)\ **Post date:** [December 18, 2002, 11:41pm UTC](https://boards.straightdope.com/t/what-happens-to-the-electrons-at-absolute-zero/143679/5 "2002-12-18T23:41:14Z")
> [@](#): > > If the electrons compeltey stop at K = 0 I’m not sure that’s true. IIRC, 0 degrees Kelvin is where molecular motion is at a minimum. There is some residual activity left that, evidently, cannot be reduced further in any circumstances. ---
**Author:** ![MC\_Master\_of\_Ceremonies](https://avatars.discourse-cdn.com/v4/letter/m/bb73d2/32.png) [@MC\_Master\_of\_Ceremonies](https://boards.straightdope.com/u/MC_Master_of_Ceremonies)\ **Post date:** [December 18, 2002, 11:42pm UTC](https://boards.straightdope.com/t/what-happens-to-the-electrons-at-absolute-zero/143679/6 "2002-12-18T23:42:40Z")
Thinking about it more at absolute zero it would have a completely defined speed, so it’s position could not be defined. ---
**Author:** ![TheBrahmanator](https://avatars.discourse-cdn.com/v4/letter/t/9de0a6/32.png) [@TheBrahmanator](https://boards.straightdope.com/u/TheBrahmanator)\ **Post date:** [December 18, 2002, 11:57pm UTC](https://boards.straightdope.com/t/what-happens-to-the-electrons-at-absolute-zero/143679/7 "2002-12-18T23:57:14Z")
I thought heat was molecular motion, not atomic? If electrons and protons have definite charges and heat meant a change in the speed of the electrons, then I’d think atoms could only exist at one temperature–any colder, and the electrons would collapse into the nuclues, while any faster and they’d escape orbit and radiate off from the atom. Unless temperature changes the radii of the orbitals? But I don’t think it does, under “normal” conditions. ---
**Author:** ![MC\_Master\_of\_Ceremonies](https://avatars.discourse-cdn.com/v4/letter/m/bb73d2/32.png) [@MC\_Master\_of\_Ceremonies](https://boards.straightdope.com/u/MC_Master_of_Ceremonies)\ **Post date:** [December 19, 2002, 12:09am UTC](https://boards.straightdope.com/t/what-happens-to-the-electrons-at-absolute-zero/143679/8 "2002-12-19T00:09:13Z")
Well, heat does effect the electrons (combustion for example), but your probably right as I thik my treatment of the electron is wrong. But electrons at absolute zero cannot occupy the higher energy levels and therfore cannot be conducted and fall into the valence band. Anyway, I think I’ve confused myself now ---
**Author:** ![DarrenS](https://avatars.discourse-cdn.com/v4/letter/d/977dab/32.png) [@DarrenS](https://boards.straightdope.com/u/DarrenS)\ **Post date:** [December 19, 2002, 1:50am UTC](https://boards.straightdope.com/t/what-happens-to-the-electrons-at-absolute-zero/143679/9 "2002-12-19T01:50:23Z")
Since absolute zero is unattainable, isn’t this rather like asking what happens to a space craft that accelerates to the speed of light? ---
**Author:** ![andy\_fl](https://avatars.discourse-cdn.com/v4/letter/a/49beb7/32.png) [@andy\_fl](https://boards.straightdope.com/u/andy_fl)\ **Post date:** [December 19, 2002, 1:59am UTC](https://boards.straightdope.com/t/what-happens-to-the-electrons-at-absolute-zero/143679/10 "2002-12-19T01:59:34Z")
I think the question is full of misconceptions as are some of the replies. Temperature is a **Macroscopic** phenomenon, not a microscopic one. There is nothing like temeperature of an atom or electron. Temperature can be thought as the average rms energy of the molecules hitting the walls or the thermometer you put in it. ---
**Author:** ![andy\_fl](https://avatars.discourse-cdn.com/v4/letter/a/49beb7/32.png) [@andy\_fl](https://boards.straightdope.com/u/andy_fl)\ **Post date:** [December 19, 2002, 2:00am UTC](https://boards.straightdope.com/t/what-happens-to-the-electrons-at-absolute-zero/143679/11 "2002-12-19T02:00:39Z")
> [@](#): > > \*Originally posted by andy\_fl \* > \*\*Temperature is a **Macroscopic** phenomenon … \*\* i meant Macroscopic property :smack: ---
**Author:** ![MC\_Master\_of\_Ceremonies](https://avatars.discourse-cdn.com/v4/letter/m/bb73d2/32.png) [@MC\_Master\_of\_Ceremonies](https://boards.straightdope.com/u/MC_Master_of_Ceremonies)\ **Post date:** [December 19, 2002, 2:04am UTC](https://boards.straightdope.com/t/what-happens-to-the-electrons-at-absolute-zero/143679/12 "2002-12-19T02:04:22Z")
Scientists still measue temperatures on a microscopic scale, most of the experiments involved in creating temp.'s near absolute zero only involve a comparitvely small number of molecules. ---
**Author:** ![zigaretten](https://avatars.discourse-cdn.com/v4/letter/z/91b2a8/32.png) [@zigaretten](https://boards.straightdope.com/u/zigaretten)\ **Post date:** [December 19, 2002, 2:15am UTC](https://boards.straightdope.com/t/what-happens-to-the-electrons-at-absolute-zero/143679/13 "2002-12-19T02:15:54Z")
For the OP: [this site](http://newton.dep.anl.gov/askasci/phy00/phy00423.htm) Quote: Even at absolute zero there is motion. It is just that all the matter is in its lowest vibrational state and therefore cannot lose energy to its environment. …even at absolute zero, some motion is necessary (zero-point energy) by Heisenberg’s Uncertainty Principle. Since the uncertainty in a particle’s position times the uncertainty in its momentum must be greater than Planck’s constant, if a particle is constrained in its position at all, it’s momentum must have some uncertainty, which means it cannot be zero. For example, **electrons in atoms must still move in their orbits**. ---
**Author:** ![KarlGauss](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/karlgauss/32/3713_2.png) [@KarlGauss](https://boards.straightdope.com/u/KarlGauss)\ **Post date:** [December 19, 2002, 3:07am UTC](https://boards.straightdope.com/t/what-happens-to-the-electrons-at-absolute-zero/143679/14 "2002-12-19T03:07:22Z")
> [@](#): > > \*Originally posted by andy\_fl \* > \*\*i meant Macroscopic property :smack: \*\* Not that I know anything about physics, but if it is strictly the case that temperature is a macroscopic property, then why are entities such as “[high temperature protons](http://faculty.erau.edu/ericksol/courses/sp300/ch3/solar_rad_ch3.html)” referred to in the [study of the solar wind](http://www-istp.gsfc.nasa.gov/scripts/sw-cat/catalog_categonew.html)? There are also many references to “high temperature electrons”, but I won’t bother to list any sites/cites. In these contexts, what does a “high temperature proton/electron” mean? Is it just imprecise jargon? N.B. [I asked a similar question a while back](http://boards.straightdope.com/sdmb/showthread.php?s=&threadid=32642&highlight=high+and+temperature) but I’m not sure it was ever answered satisfactorily (IMO) ---
**Author:** ![zigaretten](https://avatars.discourse-cdn.com/v4/letter/z/91b2a8/32.png) [@zigaretten](https://boards.straightdope.com/u/zigaretten)\ **Post date:** [December 19, 2002, 6:50am UTC](https://boards.straightdope.com/t/what-happens-to-the-electrons-at-absolute-zero/143679/15 "2002-12-19T06:50:58Z")
> [@](#): > > \*Originally posted by KarlGauss \* > Not that I know anything about physics, but if it is strictly the case that temperature is a macroscopic property, then why are entities such as “[high temperature protons](http://faculty.erau.edu/ericksol/courses/sp300/ch3/solar_rad_ch3.html)” referred to in the [study of the solar wind](http://www-istp.gsfc.nasa.gov/scripts/sw-cat/catalog_categonew.html)? Both the sun and the solar wind are gases (or more precisely plasmas) made up of many protons and electrons. In other words, they are macroscopic systems. In the above sites the references to “high temperature protons” seem to me to simply be shorthand for “protons which are elements of this high temperature macroscopic system. In a similar vein, I could refer to the properties of “a liquid molecule” even though it takes more than one molecule to form a liquid. I think that in this case the problem is just semantics. > [@](#): > > N.B. [I asked a similar question a while back](http://boards.straightdope.com/sdmb/showthread.php?s=&threadid=32642&highlight=high+and+temperature) but I’m not sure it was ever answered satisfactorily (IMO) I can’t give you a definite answer to this one without seeing the article to which you refer (and even then I don’t know if I could give you an answer, but what the heck) however…… Astronomers are weird. They like to deal with something they define as a “virial temperature.” This is based on a “virial energy” which is based on assumptions about the relationship between the total, potential and kinetic energies which I, quite frankly, don’t really understand. But, as can be seen at [this site](http://nedwww.ipac.caltech.edu/level5/March01/Rees/Rees3.html) they are in the habit of assigning a temperature to individual protons based on the assumption that each proton will be at the “virial temperature” (which you will recall is still actually an average value for a macroscopic system). > [@](#): > > ……calculated on the **assumption that the ions at each radius are at the virial temperature** [i.e. kTi = mp c2 (r / rg)-1]. This assumption is self-consistent because bremsstrahlung cooling and electron-ion coupling are indeed ineffective…… > > and > > …The proton temperature is taken as the virial temperature… I suspect that your article may have used similar assumptions with respect to some similar virial temperature. ---
**Author:** ![KarlGauss](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/karlgauss/32/3713_2.png) [@KarlGauss](https://boards.straightdope.com/u/KarlGauss)\ **Post date:** [December 19, 2002, 9:02pm UTC](https://boards.straightdope.com/t/what-happens-to-the-electrons-at-absolute-zero/143679/16 "2002-12-19T21:02:06Z")
Many thanks, **zigaretten** , for your detailed and helpful response. I think I am beginning to see that a lot of the problem is semantic (and, of course, other stuff that I don’t understand). ---
**Author:** ![GusNSpot](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gusnspot/32/436_2.png) [@GusNSpot](https://boards.straightdope.com/u/GusNSpot)\ **Post date:** [December 19, 2002, 9:18pm UTC](https://boards.straightdope.com/t/what-happens-to-the-electrons-at-absolute-zero/143679/17 "2002-12-19T21:18:00Z")
And of course just making the observation … ::: flee ::; ---
**Author:** ![chukhung](https://avatars.discourse-cdn.com/v4/letter/c/e79b87/32.png) [@chukhung](https://boards.straightdope.com/u/chukhung)\ **Post date:** [December 19, 2002, 10:53pm UTC](https://boards.straightdope.com/t/what-happens-to-the-electrons-at-absolute-zero/143679/18 "2002-12-19T22:53:04Z")
> [@](#): > > \*Originally posted by Alietta \* > \*\*If the electrons compeltey stop at K = 0 then where do they go? Are they frozen in space? Do they fall to the ground? My chemistry teacher could not explain this. \*\* You may want to do some research on “Bose-Einstein Condensate”. From this site, [http://www.nist.gov/public\_affairs/releases/cornellbose.htm](http://www.nist.gov/public_affairs/releases/cornellbose.htm) > [@](#): > > Predicted in 1924 by Albert Einstein, who built on the work of Satyendra Nath Bose, the condensation occurs when individual atoms meld into a “superatom” behaving as a single entity at just a few hundred billionths of a degree above absolute zero. I leave if for the physicists to further explain the remarkable properties of this form of matter.