# What is the coldest possible temperature?
**URL:** https://boards.straightdope.com/t/what-is-the-coldest-possible-temperature/200825
**Category:** Factual Questions
**Created:** [September 10, 2003, 7:37pm UTC](https://boards.straightdope.com/t/what-is-the-coldest-possible-temperature/200825 "2003-09-10T19:37:34Z")
**Posts on this page:** 8
**Page:** 3
### Author:  [@filmore](https://boards.straightdope.com/u/filmore)
#### Post date: [September 12, 2003, 2:24pm UTC](https://boards.straightdope.com/t/what-is-the-coldest-possible-temperature/200825/41 "2003-09-12T14:24:29Z")
> [@](#):
>
> \*Originally posted by Whack-a-Mole \*
> \*\*That makes sense on the face of it but remember that temperature is an indicator of motion. To go cold all you want to do is slow down the object (or atoms in that object) that you are trying to cool. \*\*
I hope people are still reading this thread because here’s something I’ve always wondered about Bose-Einstein Condensate: How does the atom know it’s stopped? It’s only stopped relative to the table top on which the experiment is being peformed. It’s still rotating around the earth rotating around the sun and so on. If I was on an airplane zooming over the “stopped” atom, would I be able to observe the Bose-Einstein Condensate since the atom was not stopped relative to me? Or if the experiment was being performed on a moving train, would an observer standing still outside the train be able to observe the condensate?
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### Author:  [@Hampshire](https://boards.straightdope.com/u/Hampshire)
#### Post date: [September 12, 2003, 2:30pm UTC](https://boards.straightdope.com/t/what-is-the-coldest-possible-temperature/200825/42 "2003-09-12T14:30:23Z")
If you’ve never seen anything colder than absolute zero you haven’t met my ex-wife.
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### Author:  [@flonks](https://boards.straightdope.com/u/flonks)
#### Post date: [September 12, 2003, 3:33pm UTC](https://boards.straightdope.com/t/what-is-the-coldest-possible-temperature/200825/43 "2003-09-12T15:33:18Z")
> [@](#):
>
> \*Originally posted by friedo \*
> \*\*Not that puny, since it’s absolutely correct. Energy wants to move from a source to a sink. You can’t create cold, though you can move heat from one place to another. In order to move heat, you need something cold to warm up. \*\*
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### Author:  [@MC\_Master\_of\_Ceremonies](https://boards.straightdope.com/u/MC_Master_of_Ceremonies)
#### Post date: [September 13, 2003, 12:15am UTC](https://boards.straightdope.com/t/what-is-the-coldest-possible-temperature/200825/44 "2003-09-13T00:15:22Z")
> [@](#):
>
> \*Originally posted by Hampshire \*
> \*\*If you’ve never seen anything colder than absolute zero you haven’t met my ex-wife. \*\*
Your ex-wife is easy, what the F— you complaning about?
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### Author:  [@culov](https://boards.straightdope.com/u/culov)
#### Post date: [September 13, 2003, 6:43am UTC](https://boards.straightdope.com/t/what-is-the-coldest-possible-temperature/200825/45 "2003-09-13T06:43:55Z")
[http://www.rednova.com/news/stories/2/2003/09/12/story001.html](http://www.rednova.com/news/stories/2/2003/09/12/story001.html)
heres another link…
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### Author:  [@carrielikewhoa](https://boards.straightdope.com/u/carrielikewhoa)
#### Post date: [September 13, 2003, 6:54am UTC](https://boards.straightdope.com/t/what-is-the-coldest-possible-temperature/200825/46 "2003-09-13T06:54:49Z")
Of COURSE it’s possible to reach absolute zero–just stop by your local movie theatre!
/bad joke
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### Author:  [@Napier](https://boards.straightdope.com/u/Napier)
#### Post date: [September 14, 2003, 11:34am UTC](https://boards.straightdope.com/t/what-is-the-coldest-possible-temperature/200825/47 "2003-09-14T11:34:00Z")
There is a sense in which parts of a system can get to temperatures below 0 K. That is, you can have two kinds of particles in a system, say electrons (the so-called “electron gas”) and nuclei (the part with practically all the mass) in a metal, and the two subsystems can have different temperatures. Then you have an average for the whole thing. It is important because other properties such as the diffusivity can be different for the two subsystems. There are situations where one of the subsystems can have a negative temperature.
Reference, IIRC: “Temperatures Very Low and Very High”, forget author, published by Dover.
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### Author:  [@eburacum45](https://boards.straightdope.com/u/eburacum45)
#### Post date: [September 14, 2003, 11:57am UTC](https://boards.straightdope.com/t/what-is-the-coldest-possible-temperature/200825/48 "2003-09-14T11:57:34Z")
Here is a link to some stuff about Bose-Einstein Condensates;
[http://www.colorado.edu/physics/2000/bec/index.html](http://www.colorado.edu/physics/2000/bec/index.html)
some interesting educational games to play concerned with low temperature physics
Having lost this link somebody kindly retrieved it for me…
Thank you!
* * *
SF worldbuilding at
[http://www.orionsarm.com/main.html](http://www.orionsarm.com/main.html)
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