Timeline for Why is absolute zero unattainable?
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| Dec 5, 2017 at 7:38 | history | edited | paracetamol | CC BY-SA 3.0 |
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| Mar 16, 2017 at 12:52 | history | protected | orthocresol | ||
| Mar 16, 2017 at 0:31 | answer | added | ParaH2 | timeline score: 5 | |
| Dec 28, 2016 at 16:39 | history | edited | paracetamol | CC BY-SA 3.0 |
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| Dec 20, 2016 at 15:28 | history | edited | paracetamol | CC BY-SA 3.0 |
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| Dec 15, 2016 at 14:33 | history | edited | paracetamol | CC BY-SA 3.0 |
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| S Dec 4, 2016 at 19:20 | history | bounty ended | paracetamol | ||
| S Dec 4, 2016 at 19:20 | history | notice removed | paracetamol | ||
| Nov 30, 2016 at 6:05 | history | edited | paracetamol | CC BY-SA 3.0 |
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| S Nov 30, 2016 at 5:24 | history | bounty started | paracetamol | ||
| S Nov 30, 2016 at 5:24 | history | notice added | paracetamol | Authoritative reference needed | |
| Nov 28, 2016 at 13:31 | history | edited | paracetamol | CC BY-SA 3.0 |
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| Nov 21, 2016 at 12:53 | history | edited | paracetamol | CC BY-SA 3.0 |
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| Oct 26, 2016 at 16:02 | history | edited | paracetamol | CC BY-SA 3.0 |
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| Oct 25, 2016 at 22:02 | answer | added | Li Zhi | timeline score: -2 | |
| Oct 25, 2016 at 19:17 | history | edited | paracetamol | CC BY-SA 3.0 |
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| Oct 20, 2016 at 8:08 | comment | added | porphyrin | I think that what I wrote is correct in the context of the question but not complete in a general sense. The average energy, translation, vibration, rotation is $<E>=k_BT/2$ for each 'squared' energy term with $k_B$ being Boltzmann's constant. This assumes that a Boltzmann distribution applies, i.e. that each energy level has a smaller population than the one immediately below it in energy and that the number of levels is infinite. A population inversion as in the laser or in nuclear spin pulsed NMR experiments is then described as having a negative temperature but just for those levels. | |
| Oct 19, 2016 at 16:09 | history | edited | paracetamol | CC BY-SA 3.0 |
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| Oct 15, 2016 at 23:05 | comment | added | The Vee | @porphyrin Temperature is not a measure of motional energy. All it is is a ratio between dU and dS at constant V and N. That's how it can be negative in many exotic systems and (effectively) in some that have become quite familiar, for example. You can perfectly have motion at $T=0$. A harmonic oscillator does. | |
| Oct 15, 2016 at 11:46 | answer | added | yeoman | timeline score: 12 | |
| Oct 14, 2016 at 14:38 | vote | accept | paracetamol | ||
| Oct 14, 2016 at 14:37 | vote | accept | paracetamol | ||
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| Oct 14, 2016 at 13:08 | answer | added | Andrei | timeline score: 9 | |
| Oct 14, 2016 at 10:17 | answer | added | Isobutane | timeline score: 18 | |
| Oct 14, 2016 at 6:55 | answer | added | MariusM | timeline score: 8 | |
| Oct 14, 2016 at 0:28 | history | tweeted | twitter.com/StackChemistry/status/786725312952492033 | ||
| Oct 13, 2016 at 22:26 | history | edited | orthocresol | CC BY-SA 3.0 |
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| Oct 13, 2016 at 21:58 | answer | added | Ivan Neretin | timeline score: 173 | |
| Oct 13, 2016 at 21:13 | comment | added | porphyrin | Both explanations are wrong. (a) It is quite possible nowadays to obtain temperatures in the milli-kelvin range. This is done to remove thermal noise on very sensitive instruments. (b) very briefly, temperature is a measure of motional energy, molecule still have what is called zero-point vibrational energy at zero K, and crystals have lattice motion (phonons) that also have zero point energies, so it is not true that the total energy is zero at zero K. Atoms still have the same electronic energy as at room temperature. | |
| Oct 13, 2016 at 21:07 | answer | added | Cort Ammon | timeline score: 78 | |
| Oct 13, 2016 at 18:54 | comment | added | Jon Custer | Since systems can only approach it logarithmically, one would have to seriously question if it is physically possible. | |
| Oct 13, 2016 at 18:20 | history | edited | paracetamol | CC BY-SA 3.0 |
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| Oct 13, 2016 at 18:18 | comment | added | Ivan Neretin | Both are utter nonsense. Absolute zero is physically possible (not that we can attain it, though). | |
| Oct 13, 2016 at 18:04 | history | asked | paracetamol | CC BY-SA 3.0 |