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Lies, Damned Lies, and Quantum Statistics

Posted by samzenpus on from the do-the-math dept.

quax writes "Getting a scientific paper published that goes against the grain of conventional wisdom was never easy. Especially when it seems to contain an obvious glaring mistake. Fortunately despite already being some kind of pop celebrity with no shortage of fan mail, Einstein still opened letters he received from strangers. And this is how a trivial, fateful counting mistake was able to change the course of physics forever."

17 of 53 comments (clear)

  1. uhuh by Anonymous Coward · · Score: 5, Funny

    Dear theoretical physicists,

    Admit that most of your fields have become a branch of overpriced mathematics and stop boring us with your tales of 100 years ago.

    1. Re:uhuh by mister2au · · Score: 4, Interesting

      or are the physicists the abstract artists of the science world while the mathematicians are the boring paint suppliers?

      just saying ...

    2. Re:uhuh by RatherBeAnonymous · · Score: 4, Informative

      Physicists don't think that mathematics and physics are the same thing.

      When I was a physics undergrad in the mid-90's I was advised against going into the Mathematical Physics program by one of my PHD physics professors. He told me, and I'm paraphrasing, that mathematical physicists rarely make groundbreaking discoveries. He claimed the field is hampered by trying to get the math right, and that there are equations that, while being technically incorrect, are useful in general even though they fall apart in edge cases, and that many mathematical physicists find using such equations distasteful. I dropped out of physics a long time ago so I don't have my own opinion on the quality of mathematical physicists as researchers.

  2. But in the year 2012... by Anonymous Coward · · Score: 5, Funny

    ...due to a 500 internal server error and a useless summary that is written to bait and not inform, we won't learn what that mistake was and how it changed the course of physics forever.

    1. Re:But in the year 2012... by stms · · Score: 4, Informative

      Always check Google's cache.

    2. Re:But in the year 2012... by Alkonaut · · Score: 5, Funny

      I think slashdotters observing the state of the server has changed the state of it.

    3. Re:But in the year 2012... by Razgorov+Prikazka · · Score: 4, Funny

      Shooting servers through one of two small slits is enough I guess...

      --
      rm -rf --no-preserve-root / ...and let /dev/null sort them out...
    4. Re:But in the year 2012... by Anonymous Coward · · Score: 4, Informative

      Lies, Damned Lies, and Quantum Statistics?
      Posted on August 4, 2012 by Henning Dekant

      Statistics has a bad reputation, and has had for a long time, as demonstrated by Mark Twain's famous quote that I paraphrased to use as the title of this blog post.

      Of course physics is supposed to be above the fudging of statistical numbers to make a point. Well, on second thought, theoretical physics should be above fudging (in the experimental branch, things are not so clear cut).

      Statistical physics is strictly about employing all mathematically sound methods to deal with uncertainty. This program turned out to be incredibly powerful, and gave a sound foundation to the thermodynamic laws. The latter were empirically derived previously, but only really started to make sense once statistical mechanics came into its own, and temperature was understood to be due to the Brownian motion. Incidentally, this was also the field that first attracted a young Einstein's attention. Among all his other accomplishments, his paper on the matter that finally settled the debate if atoms were for real or just a useful model is often overlooked. (It is mindboggling that within a short span 0f just 40 years ('05-'45) science went from completely accepting the reality of atoms, to splitting them and unleashing nuclear destruction).

      Having early on cut his teeth on statistical mechanics, it shouldn't come as a surprise that Einstein's last great contribution to physics went back to this field. And it all started with fudging the numbers, in a far remote place, one that Einstein had probably never even heard of.

      In the capital of Bangladesh, a brilliant but entirely unknown scholar named Satyendra Nath Bose made a mistake when trying to demonstrate to his students that the contemporary theory of radiation was inadequate and contradicted experimental evidence. It was a trivial mistake, simply a matter of not counting correctly. What added insult to injury, it lead to a result that was in accordance with the the correct electromagnetic radiation spectrum. A lesser person may have just erased the blackboard and dismissed the class, but Bose realized that there was some deeper truth lurking beneath the seemingly trivial oversight.

      What Bose stumbled upon was a new way of counting quantum particles. Conventionally, if you have two particles that can only take on two states, you can model them as you would the probabilities for a coin toss. Lets say you toss two coins at the same time; the following table shows the possible outcomes:
      Coin 1
      Head Tail
      Coin 2 Head HH HT
      Tail TH TT

      It is immediate obvious that if you throw to coins the combination head-head will have a likelihood of 25%. But if you have the kind of "quantum coins" that Bose stumbled upon then nature behaves rather different. Nature does not distinguish between the states tails-head and head-tails i.e. the two states marked green in the table. Rather it just treats these two states as one and the same.

      In the quantum domain nature plays the ultimate shell game. If these shells were bosons the universe would not allow you to notice if they switch places.

      This means, rather than four possible outcomes in the quantum world, we only have three, and the probability for them is evenly spread, i.e. assigning a one-third chance to our heads-heads quantum coin toss.

      Bose found out the hard way that if you try to publish something that completely goes against the conventional wisdom, and you have to go through a peer review process, your chances of having your paper accepted are almost nil (some things never change).

      That's where Einstein came into the picture. Bose penned a very respectful letter to Einstein, who at the time was already the most famous scie

    5. Re:But in the year 2012... by Anonymous Coward · · Score: 5, Funny

      Describing Einstein as the Lady Gaga of Science is probably why the article is now 403 forbidden.

    6. Re:But in the year 2012... by Trepidity · · Score: 2

      You can get a better explanation from the usual source anyway.

      --
      10 PRINT CHR$(205.5+RND(1)); : GOTO 10
    7. Re:But in the year 2012... by ColdWetDog · · Score: 5, Funny

      Describing Einstein as the Lady Gaga of Science is probably why the article is now 403 forbidden.

      Dunno.

      Bad hair - check
      Bushy eyebrows - check
      Toneless whistling - check
      Incomprehensible 'lyrics' - check

      You have to admit, there are certain similarities.

      I would not be surprised to learn that Lady Gaga smokes a pipe.

      --
      Faster! Faster! Faster would be better!
  3. Re:What is this? by bryonak · · Score: 4, Interesting

    You didn't miss much, here's the cached article

    In my opinion it's a lousy written piece with half of the sentences being there for the sole purpose of filling white space.

  4. Re:Bose-Einstein Statistics by mister2au · · Score: 5, Funny

    not really sure why this is news

    I blame it on relativistic time dilation ...

    to an observer in travelling at Slashdot speed this appears to have just occurred, whilst to a stationary observer 87 years appear to have passed ...

    this dilation seems to apply uniformly across most observed Slashdot articles (albiet with yet-to-be-explained time loops as well!)

  5. Summary of the article in a Haiku by tstrunk · · Score: 2

    Science did not know
    Identical Particles
    Exist. Bose did.

    There's not much more content. Bose introduced the concept of identical particles. This lead to Bose and Fermi statistics and new insight in physics.
    Plus: Bose had trouble publishing it.

  6. Lies, Damned Lies by ygslash · · Score: 3, Informative

    ...as demonstrated by Mark Twain's famous quote that I paraphrased to use as the title of this blog post.

    Sorry, that's a damned lie.

    Mark Twain attributed the quote to Disraeli, not to himself. But even that attribution is now considered inaccurate, as described by The University of York Department of Mathematics and on this Wikipedia page.

  7. bogus slashdot summary by bcrowell · · Score: 3, Insightful

    The slashdot summary is completely garbled. It contains this sentence: "Especially when it seems to contain an obvious glaring mistake." There is nothing like this in the article. The mistake described in the article is a mistake that Bose made during a lecture, which happened to lead to a calculation that described how nature actually works. By the time Bose wrote his paper, there was not "an obvious glaring mistake." It was now presented as a scientific hypothesis, intentionally formed, about how nature actually works.

    --
    Find free books.
    1. Re:bogus slashdot summary by quax · · Score: 2

      1) Did he actually make a mistake in his lecture?

      2) Did he realize this was a mistake? When?

      3) Was there a mistake in his paper and research?

      1) When he lectured on the suspect he wanted to demonstrate how the know statistical physics did not produce the Planck law but rather the ultraviolet catastrophe. Hence he wanted to demonstrate that the theory at the time was faulty. But he made a "mistake" along the way and out popped Planck's law.

      The "mistake" was the way that you count the states available to a photon. I.e. as illustrated in the coin toss example nature doesn't count photons as distinguishable particles like coins. Nature counts head-tail and tail-head as only one state.

      This is obviously wrong in the macroscopic domain. Bose realized that this "mistake" must actually correctly reflect how nature accounts for states in the quantum domain.

      2) During or shortly after his lecture Bose must have realized that his "mistake" must actually reflect the correct statistics for photons.

      3) We now know that Bose's static is entirely correct for Bosons, but at the time all particles were imagined to exhibit the same statistic as macroscopic particles. I.e. they were thought to be always properly distinguishable. But it turns out you cannot put "labels" on Bosons, not even theoretically. I.e. if you have two identical Lego pieces and you exchange them between two identical Lego projects, you may not be able to immediately tell the difference, but you know that a real change occurred and you could make this explicit by labeling and keeping track of the Lego bricks. At the quantum domain there is no equivalence to this, in a quantum "Lego" project (e.g, a Bose-Einstein condensate) nature will not make a difference, not even in principle, if you exchange two identical particles that are in the same quantum state. Actually, even the concept of such an exchange loses all meaning.