# Does bacteria exist in sub-absolute zero temperatures? **URL:** \ **Category:** Factual Questions\ **Created:** [November 27, 2016, 4:10pm UTC](https://boards.straightdope.com/t/does-bacteria-exist-in-sub-absolute-zero-temperatures/773167 "2016-11-27T16:10:02Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![davidmich](https://avatars.discourse-cdn.com/v4/letter/d/e56c9b/32.png) [@davidmich](https://boards.straightdope.com/u/davidmich)\ **Post date:** [November 27, 2016, 4:10pm UTC](https://boards.straightdope.com/t/does-bacteria-exist-in-sub-absolute-zero-temperatures/773167/1 "2016-11-27T16:10:02Z")
Hi Does bacteria exist in sub-absolute zero temperatures? I have looked but have found no websites with any mention of it. I look forward to your feedback ---
**Author:** ![running\_coach](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/running_coach/32/15836_2.png) [@running\_coach](https://boards.straightdope.com/u/running_coach)\ **Post date:** [November 27, 2016, 4:13pm UTC](https://boards.straightdope.com/t/does-bacteria-exist-in-sub-absolute-zero-temperatures/773167/2 "2016-11-27T16:13:07Z")
Absolute zero means you can’t go any lower. ---
**Author:** ![Terminus\_Est](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/terminus_est/32/3087_2.png) [@Terminus\_Est](https://boards.straightdope.com/u/Terminus_Est)\ **Post date:** [November 27, 2016, 4:14pm UTC](https://boards.straightdope.com/t/does-bacteria-exist-in-sub-absolute-zero-temperatures/773167/3 "2016-11-27T16:14:47Z")
Absolute zero is the coldest temperature that can ever be, characterized by the complete absence of all molecular and atomic motion. So, no, there are no bacteria that exist in sub-absolute zero temperatures because nothing can be colder than absolute zero. Maybe you are thinking of some other temperature? Below freezing, perhaps? ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [November 27, 2016, 4:19pm UTC](https://boards.straightdope.com/t/does-bacteria-exist-in-sub-absolute-zero-temperatures/773167/4 "2016-11-27T16:19:05Z")
ETA: double-ninja’d. Shoulda refreshed. There is no such thing as sub-absolute zero temperatures. That’s a meaningless concept. Give us some more context on what you think you read and perhaps we can tease out the rest of what you’re looking for. ---
**Author:** ![davidmich](https://avatars.discourse-cdn.com/v4/letter/d/e56c9b/32.png) [@davidmich](https://boards.straightdope.com/u/davidmich)\ **Post date:** [November 27, 2016, 4:26pm UTC](https://boards.straightdope.com/t/does-bacteria-exist-in-sub-absolute-zero-temperatures/773167/5 "2016-11-27T16:26:31Z")
> [@LSLGuy](#): > > ETA: double-ninja’d. Shoulda refreshed. > > There is no such thing as sub-absolute zero temperatures. That’s a meaningless concept. > > Give us some more context on what you think you read and perhaps we can tease out the rest of what you’re looking for. > **[Quantum Gas Goes below Absolute Zero](https://www.scientificamerican.com/article/quantum-gas-goes-below-absolute-zero/)** > > Ultracold atoms pave way for negative-Kelvin materials > **[MIT team achieves coldest temperature ever](https://news.mit.edu/2003/cooling)** ---
**Author:** ![davidmich](https://avatars.discourse-cdn.com/v4/letter/d/e56c9b/32.png) [@davidmich](https://boards.straightdope.com/u/davidmich)\ **Post date:** [November 27, 2016, 4:27pm UTC](https://boards.straightdope.com/t/does-bacteria-exist-in-sub-absolute-zero-temperatures/773167/6 "2016-11-27T16:27:37Z")
> [@davidmich](#): > > [Quantum Gas Goes below Absolute Zero | Scientific American](https://www.scientificamerican.com/article/quantum-gas-goes-below-absolute-zero/) > [MIT team achieves coldest temperature ever | MIT News | Massachusetts Institute of Technology](http://news.mit.edu/2003/cooling) > **[Quantum Gas Temperature Goes Below Absolute Zero](https://scitechdaily.com/quantum-gas-temperature-goes-below-absolute-zero/)** > > Physicists have been able to create an atomic gas that can attain a temperature below absolute zero, -273.15˚C (-459.67˚F). They were able to create this gas using negative-Kelvin materials and new quantum devices. The scientists published their... ---
**Author:** ![lazybratsche](https://avatars.discourse-cdn.com/v4/letter/l/ba8739/32.png) [@lazybratsche](https://boards.straightdope.com/u/lazybratsche)\ **Post date:** [November 27, 2016, 4:37pm UTC](https://boards.straightdope.com/t/does-bacteria-exist-in-sub-absolute-zero-temperatures/773167/7 "2016-11-27T16:37:52Z")
The actual sub-zero temperatures in those references was in a tiny quantity of atoms, in an artificial and precisely controlled laser trap apparatus. There’s certainly no bacteria in the cloud of laser-trapped atoms. If there is any on the inside of the apparatus, it’ll be above absolute zero. But I’d hazard a guess that this sort of equipment is cleaned thoroughly enough to be sterile. ---
**Author:** ![davidmich](https://avatars.discourse-cdn.com/v4/letter/d/e56c9b/32.png) [@davidmich](https://boards.straightdope.com/u/davidmich)\ **Post date:** [November 27, 2016, 4:52pm UTC](https://boards.straightdope.com/t/does-bacteria-exist-in-sub-absolute-zero-temperatures/773167/8 "2016-11-27T16:52:48Z")
> [@lazybratsche](#): > > The actual sub-zero temperatures in those references was in a tiny quantity of atoms, in an artificial and precisely controlled laser trap apparatus. There’s certainly no bacteria in the cloud of laser-trapped atoms. If there is any on the inside of the apparatus, it’ll be above absolute zero. But I’d hazard a guess that this sort of equipment is cleaned thoroughly enough to be sterile. Thanks lazybratsche. I had seen this wikipedia article(see below) and thought perhaps given the info on new research on sub-absolute zero temperatures that there were some possibility of bacteria at those temperatures (below absolute zero, -273.15˚C.) > **[Quantum Gas Temperature Goes Below Absolute Zero](https://scitechdaily.com/quantum-gas-temperature-goes-below-absolute-zero/)** > > Physicists have been able to create an atomic gas that can attain a temperature below absolute zero, -273.15˚C (-459.67˚F). They were able to create this gas using negative-Kelvin materials and new quantum devices. The scientists published their... > **[Tardigrade](https://webcache.googleusercontent.com/search?q=cache:kKIV-7PXs1UJ:https:%2F%2Fen.wikipedia.org%2Fwiki%2FTardigrade%2B&cd=10&hl=zh-TW&ct=clnk&gl=hk)** > > Tardigrades (/ˈtɑːrdɪɡreɪdz/), known colloquially as water bears or moss piglets, are a phylum of eight-legged segmented micro-animals. They were first described by the German zoologist Johann August Ephraim Goeze in 1773, who called them Kleiner Wasserbär ('little water bear'). In 1777, the Italian biologist Lazzaro Spallanzani named them Tardigrada (/tɑːrˈdɪɡrədə/), which means "slow steppers". > They have been found in diverse regions of Earth's biosphere – mountaintops, the deep sea, tropica... “Tardigrades are notable for being the most resilient animal: they can survive extreme conditions that would be rapidly fatal to nearly all other known life forms. They can withstand temperature ranges from 1 K (−458 °F; −272 °C) (close to absolute zero) to about 420 K (300 °F; 150 °C),[7] pressures about six times greater than those found in the deepest ocean trenches, ionizing radiation at doses hundreds of times higher than the lethal dose for a human, and the vacuum of outer space.[8] They can go without food or water for more than 30 years, drying out to the point where they are 3% or less water, only to rehydrate, forage, and reproduce.[3][9][10][11]” ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [November 27, 2016, 6:24pm UTC](https://boards.straightdope.com/t/does-bacteria-exist-in-sub-absolute-zero-temperatures/773167/9 "2016-11-27T18:24:30Z")
What precisely is meant by “sub-absolute-zero” in those articles is a very subtle technical point, but suffice to say that they don’t mean the same thing by “temperature” that laymen do. ---
**Author:** ![TSBG](https://avatars.discourse-cdn.com/v4/letter/t/77aa72/32.png) [@TSBG](https://boards.straightdope.com/u/TSBG)\ **Post date:** [November 27, 2016, 6:35pm UTC](https://boards.straightdope.com/t/does-bacteria-exist-in-sub-absolute-zero-temperatures/773167/10 "2016-11-27T18:35:11Z")
I’m no scientist, but from what I understand of the behavior of the atoms described in the SciAm article, a theoretical bacterium subjected to the same conditions couldn’t survive. Seems as though if it were even possible the thing would be torn apart as its component atoms reconfigure themselves. ---
**Author:** ![davidmich](https://avatars.discourse-cdn.com/v4/letter/d/e56c9b/32.png) [@davidmich](https://boards.straightdope.com/u/davidmich)\ **Post date:** [November 27, 2016, 7:50pm UTC](https://boards.straightdope.com/t/does-bacteria-exist-in-sub-absolute-zero-temperatures/773167/11 "2016-11-27T19:50:32Z")
> [@Chronos](#): > > What precisely is meant by “sub-absolute-zero” in those articles is a very subtle technical point, but suffice to say that they don’t mean the same thing by “temperature” that laymen do. Thank you Chronos. Can you perhaps explain the misunderstanding laymen have on this point? ---
**Author:** ![Riemann](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/riemann/32/3133_2.png) [@Riemann](https://boards.straightdope.com/u/Riemann)\ **Post date:** [November 27, 2016, 7:54pm UTC](https://boards.straightdope.com/t/does-bacteria-exist-in-sub-absolute-zero-temperatures/773167/12 "2016-11-27T19:54:05Z")
> [@davidmich](#): > > Thank you Chronos. Can you perhaps explain the misunderstanding laymen have on this point? > **[PhysicsCentral](https://physicscentral.com/explore/action/negative-temperature.cfm)** > > Learn about public engagement activities from the American Physical Society I found the above as a starting point, but I’m hoping Chronos can give us some better intuition. It seems to rest on the technical thermodynamic definition of temperature that’s based on entropy. ETA: there’s a Wiki too > **[Negative temperature](https://en.wikipedia.org/wiki/Negative_temperature)** > > Certain systems can achieve negative thermodynamic temperature; that is, their temperature can be expressed as a negative quantity on the Kelvin or Rankine scales. This should be distinguished from temperatures expressed as negative numbers on non-thermodynamic Celsius or Fahrenheit scales, which are nevertheless higher than absolute zero. A system with a truly negative temperature on the Kelvin scale is hotter than any system with a positive temperature. If a negative-temperature system and a... ---
**Author:** ![davidmich](https://avatars.discourse-cdn.com/v4/letter/d/e56c9b/32.png) [@davidmich](https://boards.straightdope.com/u/davidmich)\ **Post date:** [November 27, 2016, 7:57pm UTC](https://boards.straightdope.com/t/does-bacteria-exist-in-sub-absolute-zero-temperatures/773167/13 "2016-11-27T19:57:50Z")
> [@davidmich](#): > > Thank you Chronos. Can you perhaps explain the misunderstanding laymen have on this point? The concept of absolute zero/sub-absolute zero seems to be a theoretical value only, not a physically achievable one. So I guess I misunderstood that point. Would that be correct? ---
**Author:** ![Riemann](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/riemann/32/3133_2.png) [@Riemann](https://boards.straightdope.com/u/Riemann)\ **Post date:** [November 27, 2016, 8:08pm UTC](https://boards.straightdope.com/t/does-bacteria-exist-in-sub-absolute-zero-temperatures/773167/14 "2016-11-27T20:08:57Z")
There are certainly interesting related questions, though. A good definition of “life” is a machine to harness energy flow in order to maintain low entropy. [QUOTE=Boltzmann] The general struggle for existence of animate beings is not a struggle for raw materials – these, for organisms, are air, water and soil, all abundantly available – nor for energy which exists in plenty in any body in the form of heat, but a struggle for [negative] entropy, which becomes available through the transition of energy from the hot sun to the cold earth. [/QUOTE] > **[Entropy and life](https://en.wikipedia.org/wiki/Entropy_and_life)** > > Research concerning the relationship between the thermodynamic quantity entropy and both the origin and evolution of life began around the turn of the 20th century. In 1910 American historian Henry Adams printed and distributed to university libraries and history professors the small volume A Letter to American Teachers of History proposing a theory of history based on the second law of thermodynamics and on the principle of entropy. > The 1944 book What is Life? by Nobel-laureate physicist Erwin... ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [November 27, 2016, 9:26pm UTC](https://boards.straightdope.com/t/does-bacteria-exist-in-sub-absolute-zero-temperatures/773167/15 "2016-11-27T21:26:49Z")
I wouldn’t actually say that lay folks have a misconception about temperature. Rather, there’s a concept called “temperature” which is familiar to lay people, and which is a perfectly valid and useful concept. Under this concept, there is in fact a lowest possible temperature, which can never actually be reached but only approached, and this concept of temperature is applicable to questions like asking whether an organism can survive in an environment at that temperature. But then physicists started noticing that there are other phenomena which are not exactly the same thing as classical “temperature” (for one thing, some of these other phenomena are allowed to have negative or even infinite values), but which are very closely analogous to it in a wide variety of ways. They’re so closely analogous, in fact, that it makes sense to call them by the same name. But they still occur in different contexts, sufficiently different that one can’t (for example) speak of bacteria or tardigrades being in such an environment. It’s sort of like the distinction between hardware and software: One can speak of software having a “bug” in it, but it is _not_ the same kind of bug that Grace Hopper found short-circuiting a relay. A literal fleshy moth cannot live inside a computer program. It’s not that the program is an inhospitable environment; it’s that it’s the wrong context entirely. ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [November 27, 2016, 10:01pm UTC](https://boards.straightdope.com/t/does-bacteria-exist-in-sub-absolute-zero-temperatures/773167/16 "2016-11-27T22:01:36Z")
> [@Riemann](#): > > … > ETA: there’s a Wiki too > [Negative temperature - Wikipedia](https://en.wikipedia.org/wiki/Negative_temperature) Great link. Thank you. I hadn’t read about this stuff before. That page set me off on a nice dozen-page Wikigrination. I love a day when I learn totally new stuff. If only I could remember more of the details tomorrow. ---
**Author:** ![rbroome](https://avatars.discourse-cdn.com/v4/letter/r/838e76/32.png) [@rbroome](https://boards.straightdope.com/u/rbroome)\ **Post date:** [November 28, 2016, 1:36am UTC](https://boards.straightdope.com/t/does-bacteria-exist-in-sub-absolute-zero-temperatures/773167/17 "2016-11-28T01:36:32Z")
For an interesting discussion of negative absolute temperatures, Sixty Symbols has a good video: [![](https://img.youtube.com/vi/yTeBUpR17Rw/hqdefault.jpg "Negative Temperatures are HOT - Sixty Symbols") ](https://www.youtube.com/watch?v=yTeBUpR17Rw) ---
**Author:** ![Exapno\_Mapcase](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/exapno_mapcase/32/1051_2.png) [@Exapno\_Mapcase](https://boards.straightdope.com/u/Exapno_Mapcase)\ **Post date:** [November 28, 2016, 2:01am UTC](https://boards.straightdope.com/t/does-bacteria-exist-in-sub-absolute-zero-temperatures/773167/18 "2016-11-28T02:01:35Z")
> [@davidmich](#): > > [Tardigrade - Wikipedia](https://webcache.googleusercontent.com/search?q=cache:kKIV-7PXs1UJ:https://en.wikipedia.org/wiki/Tardigrade+&cd=10&hl=zh-TW&ct=clnk&gl=hk) > > "Tardigrades are notable for being the most resilient animal: they can survive extreme conditions that would be rapidly fatal to nearly all other known life forms. They can withstand temperature ranges from 1 K (−458 °F; −272 °C) (close to absolute zero) to about 420 K (300 °F; 150 °C),[7] … This may be part of the confusion. I can’t believe that any lifeform could survive at a temperature that liquefies helium. I know there is a footnote to a _Wired_ article, but since I have a long-standing suspicion that everything _Wired_ publishes is wrong, I tried to confirm that temperature. I couldn’t. [Smithsonian](http://www.smithsonianmag.com/science-nature/how-does-the-tiny-waterbear-survive-in-outer-space-30891298/) magazine says this: > [@](#): > > Some tardigrades, though, live on the wild side. Scientists have found the tiny creatures surviving in boiling hot springs and buried under layers of ice on Himalayan mountaintops. Experiments have shown that they can survive being frozen at -328 degrees Fahrenheit… A link in that quote goes to [Survival of Tardigrades in Extreme Environments: A Model Animal for Astrobiology](http://link.springer.com/chapter/10.1007%2F978-94-007-1896-8_12). The abstract gives no numbers, unfortunately, but it’s a true scientific article. Other sites also cite that temperature, which is -200 °C, hugely warmer than absolute zero. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [November 28, 2016, 2:19am UTC](https://boards.straightdope.com/t/does-bacteria-exist-in-sub-absolute-zero-temperatures/773167/19 "2016-11-28T02:19:54Z")
> [@](#): > > This may be part of the confusion. I can’t believe that any lifeform could survive at a temperature that liquefies helium. Actually, that I can believe. There are two main dangers to an organism from cold temperatures: That once the metabolic processes stop, they won’t start up again, and that ice crystals forming when they freeze will burst cells. By -200 C, you’re already well past both of those problems, and if the organism has survived to that point, it’s hard to see what harm any lower temperature could do. As for why they didn’t test lower temperatures, I note that -200 C is (rounded) the boiling point of nitrogen, and hence a temperature easily and cheaply achieved by a lab even with no cryo equipment, but anything colder requires something more exotic. So the simplest possibility is that they did the coldest test they could easily do, and didn’t have enough interest in pushing the limits to test anything colder. ---
**Author:** ![davidmich](https://avatars.discourse-cdn.com/v4/letter/d/e56c9b/32.png) [@davidmich](https://boards.straightdope.com/u/davidmich)\ **Post date:** [November 28, 2016, 2:40am UTC](https://boards.straightdope.com/t/does-bacteria-exist-in-sub-absolute-zero-temperatures/773167/20 "2016-11-28T02:40:34Z")
> [@Riemann](#): > > There are certainly interesting related questions, though. A good definition of “life” is a machine to harness energy flow in order to maintain low entropy. > > [Entropy and life - Wikipedia](https://en.wikipedia.org/wiki/Entropy_and_life) Fascinating stuff! Thanks Riemann. [Next page](https://boards.straightdope.com/t/does-bacteria-exist-in-sub-absolute-zero-temperatures/773167.md?page=2)