65 ms·

Absolute Zero

249 points by jqm 12y ago

quarterwave 12y ago
A discussion of the Third Law and the Nernst unattainability principle can be found in: http://benthamscience.com/open/totherj/articles/V006/1TOTHERJ.pdf http://benthamscience.com/open/totherj/articles/V006/1TOTHER...
Jun8 12y ago
I didn't knwo about this site, a true find: the writing and witticisms are fantastic, e.g. "As [sic] unspecified assistant with quick reflexes reversed the helium valve, but he turned it either the wrong way or too far, because instead of halting the flow of helium, he caused it all to be vented into the laboratory. Dewar's notes do not indicate whether a high-pitched apology was offered." (Although some proofreading would have been useful.)
- jqm 12y ago
  It's a great site. This is one of my favorite articles on it. http://www.damninteresting.com/nineteen-seventy-three/ http://www.damninteresting.com/nineteen-seventy-three/ Summary: A guy tries to build a networked central economic planning computer system.... in 1973.
- ars 12y ago
  "All that remained to liquefy was hydrogen--an odorless, colorless gas which tends to turn into a universe if left alone for a prolonged period."
  - chad_oliver 12y ago
    Also: "A chunk of helium ice would behave as a single, solid, oversized, and stupefyingly slippery atom, which may be capable of passing ghost-like through certain materials. But that's another matter altogether."
    - jkn 12y ago
      And Onnes hastened to make observations with the small container of -271°C fluid before it all evaporated away. He found it had a lower surface tension than any previously observed liquid, and just 1/8th the density of water. The modest amount of the stuff he had been able to collect behaved very curiously in general, flowing with strange characteristics and evading easy observation as if enveloped in an SEP field.
      - fahadkhan 12y ago
        Excellent I glossed over this one as I didn't know what SEP was. I maybe wrong but if it http://www.acronymfinder.com/Someone-Else's-Problem-(SEP).html http://www.acronymfinder.com/Someone-Else's-Problem-(SEP).ht... its brilliant.
        mattzito 12y ago
        It's a Hitchhiker's Guide to the Galaxy reference: http://hitchhikers.wikia.com/wiki/Somebody_Else's_Problem_field http://hitchhikers.wikia.com/wiki/Somebody_Else's_Problem_fi...
    - qq66 12y ago
      Also: "he hesitated to go Dutch on the byline."
  - clebio 12y ago
    This, indeed. I came back to paste the same. Also, "...and Dewar clearly shared (rather than reciprocated) this admiration."
- NamTaf 12y ago
  DamnInteresting is just as the name suggests. It's a fantastic site and I'm sure it's cost myself / my employer a few dollars in its time :)
coldcode 12y ago
Now this is real hard nosed science, rarely done today. I spent 6 years studying chemistry and decided to switch to programming because computers seemed unlikely to explode in my face. But I miss messing with liquid gases at cold temperatures.
- joshcanhelp 12y ago
  I'm also a chem -> programming convert. The explosions I didn't mind; it was the impossibly long production cycles that got me. After a year of work, I shelved a whole book of research notes with not so much as a mention. These days, when I'm ready to move on, I push to Github and try something new.
  - ghshephard 12y ago
    "it was the impossibly long production cycles that got me. After a year of work, I shelved a whole book of research notes with not so much as a mention. " It's funny that I have zero difficulty understanding you when you say you, "push to Github and try something new" - but I'm trying to grok what you mean when you say, "long production cycles that got to me" and "shelved a whole book of research notes with no so much as a mention" - What was happening when you were working in Chemistry?
    - clebio 12y ago
      No idea why the downvotes, I don't think they're warranted. This seems an honest question. IANAC (chemist), but could guess at the answer -- imaging trying to assemble the physical apparatus in that article: it might take weeks or months (Onnes had a battery of assistants helping him...) just to get the hardware in place, let alone orchestrate the cascade of liquids and gases that eventually produces a tiny vial of the objective. It would be something akin to building AWS from Arduinos, step-by-step, say.
      - ghshephard 12y ago
        When I read "long production cycles" - I was wondering if the OP was talking about the time that the chemical reactions took, or whether they were talking about how long it takes to write up research results - without getting any formal acknowledgment (such as in a published paper in a journal) of your results.
Monkeyget 12y ago
In Our Time episode regarding absolute zero : http://www.bbc.co.uk/programmes/b01r113g http://www.bbc.co.uk/programmes/b01r113g
- riffraff 12y ago
  bbc also appears to have a related documentary http://www.bbc.co.uk/programmes/b007v5rl/episodes/guide http://www.bbc.co.uk/programmes/b007v5rl/episodes/guide
- elemeno 12y ago
  In Our Time is a fantastic source of interesting topics, especially since all it's past episodes are available for free on the BBC's website. With over 640 episodes it shouldn't be too hard to find something of interest! For those not familiar with the show, the format is simple. A topic is picked for each week and it consists of the host, Melvyn Bragg, and three experts on that topic. The experts are then left to discuss the topic for 45 minutes with the host only interjecting to ask questions and steer the conversation. It's very much the pinnacle of listening to smart people talk about things that they're interested in. Recent episodes have covered topics as diverse as The Talmud, Photosynthesis, States of Matter, Spartacus and Early Chinese History. A list of episiodes can be found here - http://www.bbc.co.uk/programmes/b006qykl/episodes/player http://www.bbc.co.uk/programmes/b006qykl/episodes/player - and there's links on the site to download all the episodes since 2011.
pistle 12y ago
"ambiguous smears of quantum probabilities" Oh phlogiston.
cottonseed 12y ago
There was a good NOVA episode, Aboslute Zero, on the race for cold: https://www.youtube.com/watch?v=y2jSv8PDDwA https://www.youtube.com/watch?v=y2jSv8PDDwA
shaan7 12y ago
That was awesome :)
DrStalker 12y ago
It's worth pointing out that it's possible to get below absolute zero: http://www.mpg.de/6776082/negative_absolute_temperature http://www.mpg.de/6776082/negative_absolute_temperature It's a bit of a definitional thing; once you get that cold measuring how fast atomes move is less useful than looking at enthalpy and entropy and the way atoms give or receive energy. from http://en.wikipedia.org/wiki/Absolute_zero http://en.wikipedia.org/wiki/Absolute_zero > It is commonly thought of as the lowest temperature possible, but it is not the lowest enthalpy state possible
- ars 12y ago
  That's a terrible article you've linked to. And it's not really a negative temperature anyway, it's more of a notational thing, not an actual negative temperature.
  - madaxe_again 12y ago
    Potato potato... Negative temperature means that entropy decreases when you add energy to a system, typically because you're approaching a local maxima for the energy state it's in. Bose Einstein Condensates are a nice example of this behaviour.... and it's as "real" a negative temperature as you can have.
- gus_massa 12y ago
  A negative temperature is hotter than a positive temperature. Actually, it’s easier to imagine that you can’t go “bellow” zero to reach a negative temperature. You must go “over” infinity and appear at the negative side of the numbers. (If there is a mathematician nearby and begins to cry, just say that you must change the topology and use $\bar{\R}^{*}$.)
rcthompson 12y ago
My friend had himself cooled to absolute zero once. He was 0K. (Source: The internet)
Angostura 12y ago
Beautifully written, informative and witty. I did not know about the cascade of gasses method before now.
Stratoscope 12y ago
I've complained about changing titles in the past, but here's a case where the submitted title ("Absolute Zero") doesn't hold a candle to the original title: ABSOLUTE ZERO IS 0K Much, much better. 0K?
- MichaelApproved 12y ago
  I agree. I didn't pay attention to the title until I read your comment and missed this great subtly. For those that missed it, the title uses zero for the letter "O" in OK/0K. As in "zero Kelvin."
- pbhjpbhj 12y ago
  Punnery and funny titles are probably contrary to HN ethos? In any case the thrust of the article appears to be the race to be the first to produce liquid helium; that could easily have been incorporated if the HN editor wanted to make the title better. Personally I'd favour an editorial subtitle for cases where the HN editors deem the title to be less useful.
crash78 12y ago
What technique would they have used to measure the temperatures?
davidw 12y ago
> If one physically scoops up a portion of the superatom, the elevated portion acquires more gravitational potential energy than the rest, and since this is not a sustainable equilibrium for the superfluid, it will flow up and out of its container to pull itself all back into one place Is this actually doable/observable?
- haxiomic 12y ago
  It is! See this this clip http://youtu.be/2Z6UJbwxBZI http://youtu.be/2Z6UJbwxBZI
Someone 12y ago
"The municipality of Leiden has made objections as to my working with condensed gases and has not been content with asking that additional means of precaution are taken, but is gone so far to claim in August last that my cryogenic laboratory be removed from the city!" Kamerlingh Onnes' laboratory was built in the space that was created in 1806 when over 15,000 kg of gunpowder stored in a ship exploded, killing 151 people and destroying over 200 houses (http://www.pieterskerk.com/en/explore/19e-eeuw/1807/ http://www.pieterskerk.com/en/explore/19e-eeuw/1807/ That must have made the Leiden city council more cautious when hearing about potential explosions in this laboratory.
nicholassmith 12y ago
This is fascinating, I really enjoy the turn of the century science stories that come up. Big egos, big risks, fantastic results.
kbart 12y ago
Very well written and interesting article. I'm still laughing at this: "his London lab was rattled by yet another minor explosion which deprived yet another lab assistant (James Heath) of yet another eye."
- mkmk 12y ago
  There's also this fantastic subtle pun: "A chunk of helium ice would behave as a single, solid, oversized, and stupefyingly slippery atom, which may be capable of passing ghost-like through certain materials. But that's another matter altogether."
pdevr 12y ago
The site has a lot of other articles that are darn interesting.
deleted 12y ago
[deleted]

249 points by jqm 12y ago

A discussion of the Third Law and the Nernst unattainability principle can be found in: http://benthamscience.com/open/totherj/articles/V006/1TOTHERJ.pdf http://benthamscience.com/open/totherj/articles/V006/1TOTHER...

Jun8 12y ago

I didn't knwo about this site, a true find: the writing and witticisms are fantastic, e.g. "As [sic] unspecified assistant with quick reflexes reversed the helium valve, but he turned it either the wrong way or too far, because instead of halting the flow of helium, he caused it all to be vented into the laboratory. Dewar's notes do not indicate whether a high-pitched apology was offered." (Although some proofreading would have been useful.)

jqm 12y ago
It's a great site. This is one of my favorite articles on it. http://www.damninteresting.com/nineteen-seventy-three/ http://www.damninteresting.com/nineteen-seventy-three/ Summary: A guy tries to build a networked central economic planning computer system.... in 1973.
ars 12y ago
"All that remained to liquefy was hydrogen--an odorless, colorless gas which tends to turn into a universe if left alone for a prolonged period."
- chad_oliver 12y ago
  Also: "A chunk of helium ice would behave as a single, solid, oversized, and stupefyingly slippery atom, which may be capable of passing ghost-like through certain materials. But that's another matter altogether."
  - jkn 12y ago
    And Onnes hastened to make observations with the small container of -271°C fluid before it all evaporated away. He found it had a lower surface tension than any previously observed liquid, and just 1/8th the density of water. The modest amount of the stuff he had been able to collect behaved very curiously in general, flowing with strange characteristics and evading easy observation as if enveloped in an SEP field.
    - fahadkhan 12y ago
      Excellent I glossed over this one as I didn't know what SEP was. I maybe wrong but if it http://www.acronymfinder.com/Someone-Else's-Problem-(SEP).html http://www.acronymfinder.com/Someone-Else's-Problem-(SEP).ht... its brilliant.
      - mattzito 12y ago
        It's a Hitchhiker's Guide to the Galaxy reference: http://hitchhikers.wikia.com/wiki/Somebody_Else's_Problem_field http://hitchhikers.wikia.com/wiki/Somebody_Else's_Problem_fi...
  - qq66 12y ago
    Also: "he hesitated to go Dutch on the byline."
- clebio 12y ago
  This, indeed. I came back to paste the same. Also, "...and Dewar clearly shared (rather than reciprocated) this admiration."
NamTaf 12y ago
DamnInteresting is just as the name suggests. It's a fantastic site and I'm sure it's cost myself / my employer a few dollars in its time :)

coldcode 12y ago

Now this is real hard nosed science, rarely done today. I spent 6 years studying chemistry and decided to switch to programming because computers seemed unlikely to explode in my face. But I miss messing with liquid gases at cold temperatures.

joshcanhelp 12y ago
I'm also a chem -> programming convert. The explosions I didn't mind; it was the impossibly long production cycles that got me. After a year of work, I shelved a whole book of research notes with not so much as a mention. These days, when I'm ready to move on, I push to Github and try something new.
- ghshephard 12y ago
  "it was the impossibly long production cycles that got me. After a year of work, I shelved a whole book of research notes with not so much as a mention. " It's funny that I have zero difficulty understanding you when you say you, "push to Github and try something new" - but I'm trying to grok what you mean when you say, "long production cycles that got to me" and "shelved a whole book of research notes with no so much as a mention" - What was happening when you were working in Chemistry?
  - clebio 12y ago
    No idea why the downvotes, I don't think they're warranted. This seems an honest question. IANAC (chemist), but could guess at the answer -- imaging trying to assemble the physical apparatus in that article: it might take weeks or months (Onnes had a battery of assistants helping him...) just to get the hardware in place, let alone orchestrate the cascade of liquids and gases that eventually produces a tiny vial of the objective. It would be something akin to building AWS from Arduinos, step-by-step, say.
    - ghshephard 12y ago
      When I read "long production cycles" - I was wondering if the OP was talking about the time that the chemical reactions took, or whether they were talking about how long it takes to write up research results - without getting any formal acknowledgment (such as in a published paper in a journal) of your results.

Monkeyget 12y ago

In Our Time episode regarding absolute zero : http://www.bbc.co.uk/programmes/b01r113g http://www.bbc.co.uk/programmes/b01r113g

riffraff 12y ago
bbc also appears to have a related documentary http://www.bbc.co.uk/programmes/b007v5rl/episodes/guide http://www.bbc.co.uk/programmes/b007v5rl/episodes/guide
elemeno 12y ago
In Our Time is a fantastic source of interesting topics, especially since all it's past episodes are available for free on the BBC's website. With over 640 episodes it shouldn't be too hard to find something of interest! For those not familiar with the show, the format is simple. A topic is picked for each week and it consists of the host, Melvyn Bragg, and three experts on that topic. The experts are then left to discuss the topic for 45 minutes with the host only interjecting to ask questions and steer the conversation. It's very much the pinnacle of listening to smart people talk about things that they're interested in. Recent episodes have covered topics as diverse as The Talmud, Photosynthesis, States of Matter, Spartacus and Early Chinese History. A list of episiodes can be found here - http://www.bbc.co.uk/programmes/b006qykl/episodes/player http://www.bbc.co.uk/programmes/b006qykl/episodes/player - and there's links on the site to download all the episodes since 2011.

pistle 12y ago

"ambiguous smears of quantum probabilities" Oh phlogiston.

cottonseed 12y ago

There was a good NOVA episode, Aboslute Zero, on the race for cold: https://www.youtube.com/watch?v=y2jSv8PDDwA https://www.youtube.com/watch?v=y2jSv8PDDwA

shaan7 12y ago

That was awesome :)

DrStalker 12y ago

It's worth pointing out that it's possible to get below absolute zero: http://www.mpg.de/6776082/negative_absolute_temperature http://www.mpg.de/6776082/negative_absolute_temperature It's a bit of a definitional thing; once you get that cold measuring how fast atomes move is less useful than looking at enthalpy and entropy and the way atoms give or receive energy. from http://en.wikipedia.org/wiki/Absolute_zero http://en.wikipedia.org/wiki/Absolute_zero > It is commonly thought of as the lowest temperature possible, but it is not the lowest enthalpy state possible

ars 12y ago
That's a terrible article you've linked to. And it's not really a negative temperature anyway, it's more of a notational thing, not an actual negative temperature.
- madaxe_again 12y ago
  Potato potato... Negative temperature means that entropy decreases when you add energy to a system, typically because you're approaching a local maxima for the energy state it's in. Bose Einstein Condensates are a nice example of this behaviour.... and it's as "real" a negative temperature as you can have.
gus_massa 12y ago
A negative temperature is hotter than a positive temperature. Actually, it’s easier to imagine that you can’t go “bellow” zero to reach a negative temperature. You must go “over” infinity and appear at the negative side of the numbers. (If there is a mathematician nearby and begins to cry, just say that you must change the topology and use $\bar{\R}^{*}$.)

rcthompson 12y ago

My friend had himself cooled to absolute zero once. He was 0K. (Source: The internet)

Angostura 12y ago

Beautifully written, informative and witty. I did not know about the cascade of gasses method before now.

Stratoscope 12y ago

I've complained about changing titles in the past, but here's a case where the submitted title ("Absolute Zero") doesn't hold a candle to the original title: ABSOLUTE ZERO IS 0K Much, much better. 0K?

MichaelApproved 12y ago
I agree. I didn't pay attention to the title until I read your comment and missed this great subtly. For those that missed it, the title uses zero for the letter "O" in OK/0K. As in "zero Kelvin."
pbhjpbhj 12y ago
Punnery and funny titles are probably contrary to HN ethos? In any case the thrust of the article appears to be the race to be the first to produce liquid helium; that could easily have been incorporated if the HN editor wanted to make the title better. Personally I'd favour an editorial subtitle for cases where the HN editors deem the title to be less useful.

crash78 12y ago

What technique would they have used to measure the temperatures?

davidw 12y ago

> If one physically scoops up a portion of the superatom, the elevated portion acquires more gravitational potential energy than the rest, and since this is not a sustainable equilibrium for the superfluid, it will flow up and out of its container to pull itself all back into one place Is this actually doable/observable?

haxiomic 12y ago
It is! See this this clip http://youtu.be/2Z6UJbwxBZI http://youtu.be/2Z6UJbwxBZI

Someone 12y ago

"The municipality of Leiden has made objections as to my working with condensed gases and has not been content with asking that additional means of precaution are taken, but is gone so far to claim in August last that my cryogenic laboratory be removed from the city!" Kamerlingh Onnes' laboratory was built in the space that was created in 1806 when over 15,000 kg of gunpowder stored in a ship exploded, killing 151 people and destroying over 200 houses (http://www.pieterskerk.com/en/explore/19e-eeuw/1807/ http://www.pieterskerk.com/en/explore/19e-eeuw/1807/ That must have made the Leiden city council more cautious when hearing about potential explosions in this laboratory.

nicholassmith 12y ago

This is fascinating, I really enjoy the turn of the century science stories that come up. Big egos, big risks, fantastic results.

kbart 12y ago

Very well written and interesting article. I'm still laughing at this: "his London lab was rattled by yet another minor explosion which deprived yet another lab assistant (James Heath) of yet another eye."

mkmk 12y ago
There's also this fantastic subtle pun: "A chunk of helium ice would behave as a single, solid, oversized, and stupefyingly slippery atom, which may be capable of passing ghost-like through certain materials. But that's another matter altogether."

pdevr 12y ago

The site has a lot of other articles that are darn interesting.

deleted 12y ago

[deleted]