Built on Facts

You’re all familiar with Dr. Isis, also of ScienceBlogs? She likes cute things. She likes science. Despite the fact that I’m a so-square-I’m-practically-cubic reactionary, I like both of those things too. But when physicists try to make their physics cute it’s a cringe-worthy disaster waiting to happen.

In the mail today was a flier from the city municipal water supply. It contained information about the various tested properties of the city water, including contaminant levels and that sort of thing. Among the properties listed was:

Diluted Conductance: 882 μmhos/cm

*Cringe* What they’re measuring is electrical conductance, which is the inverse of electrical resistance. An object with high resistance will have low conductance and vice versa. The unit of resistance is the ohm, named after a guy named Ohm. And so some physicist decided it would be cute to call the unit for conductance the mho. Because it’s ohm backwards.

Ok, ok. It’s not too bad, even if it’s a little more of a groaner pun than I like. And I like puns. There’s also always the official non-pun name of the unit of conductance: the siemens, named after a guy named (guess what!) Siemens. But there’s worse out there.

There’s a unit of cross-sectional area used in nuclear physics equal to a trillionth of a trillionth of a square centimeter. It’s roughly the cross-section of a heavy atomic nucleus, and it’s used to discuss interactions with incoming particles. You could say in some ways it’s a measure of how easy it is to hit a nucleus with a projectile like a neutron. A big nucleus is as easy to hit as the broad side of a barn. And the unit is called the barn, for exactly that reason. I have no evidence, but I blame Feynman anyway.

Then the 70s came along and apparently a bunch of physicists were hitting the acid pretty hard when they named the quarks. “Quark” is itself pretty bonkers, coming as it does from a novel that may or may not actually have anything so bourgeois as “characters” or “a plot”. The first two quarks were named the “up” quark and “down” quark. This is just acceptable. The next two quarks were named the “charm” and “strange” quarks. Really that’s right up there with naming your children Dweezil and Moon Unit. There was an abortive attempt to name the next two quarks “truth” and “beauty” but I like to think the earth opened and swallowed whoever proposed that and their graduate students got the message and renamed them to the marginally more sedate “top” and “bottom” quarks. These days the quarks are often just referred to by letters: t quarks and such.

There’s probably more but I’m too deranged by these to remember them. At least physics didn’t produce the worst offender in the Horrible Named Things In Science category. I’m pretty sure biology did.

UPDATE: Lots of good discussion in the comments, including the fact that the guy who named that worst offender was Francis Crick, a physicist by training. I also forgot to mention the penguin diagrams of particle physcs. You think I was joking that people would have to be on something to come up with this stuff, but accoring to the guy who made this one up he was using “some illegal substance” at the time.


  1. #1 Bill
    July 6, 2009

    Which is why everyone’s favorite unit of force is a Barn-yard-atmosphere.

  2. #2 Thony C.
    July 6, 2009

    Today is the 155 anniversary of Ohm’s death!

  3. #3 bsci
    July 6, 2009

    I’m not sure you can pin Francis Crick’s naming choices on biologist. He was a physicist.

  4. #4 Uncle Al
    July 6, 2009

    Bullvalene – the first organic molecule designed not to have a static structure. Folks doubted the possibility between the discussion and the synthesis. There is a proud tradition of organic trivial names being cute (cyclone, tickle-4, arsole, dimsyl). 1,3,5-trihydroxybenzene, 1,3,5-cyclohexanetrione, and phloroglucinol are all the same molecule.

    10^(50,000) acceptable vacuum solutions in string theory sum to a joke without being cute. SUSY and SUGRA are their own punchlines. When there is no Higgs to be found what will all the folks do, giggle or whine about Yukawa potentials?

  5. #5 TW
    July 6, 2009

    No characters in Ulysses? What is Leopold Bloom, a barn? No plot. Leo loves Molly, Molly loves Leo, they have a rough day. Leo hangs with Stephen. It all comes together yes, yes, yes.

  6. #6 Sweetwater Tom
    July 6, 2009

    Back when I was in college, when dinosaurs roamed the earth, the unit of conductance WAS the mho. I think of it as a lack of imagination rather than exaggerated cuteness. As for the quark, what do you name something that has no corollary in human experience? Can’t a physicist have some fun once in a while? 😀

    The $.02 of an ordinary person,


  7. #7 Jesse
    July 6, 2009

    You could always look to Plasma Physics, where the namers seemed to be hungry all the time: Banana Orbits, Sausage modes, Kidney bean profile, potatoes… Not to mention Kinks, Bootstrap current and ballooning modes.

  8. #8 Abby Normal
    July 6, 2009

    It could be worse.

  9. #9 Stephen P
    July 6, 2009

    For other failures of cuteness, there’s the evo-devo mob, with their gene names like tinman, shavenbaby, buttonhead and Sonic hedgehog.

  10. #10 Winter Toad
    July 6, 2009

    Actually, the barn is significantly larger than a typical nucleus. As I recall, the electromagnetic probing of a nucleus determined its size to be something on the order of several square femtometres, but when they went on to low-energy neutron scattering they got a scattering cross-section that was about 100 times larger, leading somebody to remark that the thing was “as big as a barn”. I took that as indicating surprise at the disparity in cross-sections.

    And speaking of quarks, my high-energy physics professor in undergrad said there were different opinions about what colours to use in the colour charges. A faction from the U.S. wanted to use red, white, and blue instead of red, green, and blue, but that idea lost out on general aesthetic grounds (a “white” particle would not be colourless, for one thing).

  11. #11 BAllanJ
    July 6, 2009

    I heard an explanation for why the move from “truth/beauty” to “top/bottom”. High energy physics being so cash dependent and needing govt funding… they just knew that no politician was going to give them money to search for “truth”

  12. #12 Excited State
    July 6, 2009

    “Three quarks for Muster Mark” comes from Finnegans Wake, not Ulysses, as Matt correctly linked to. Haven’t read Finnegans Wake, but it certainly is supposed to abandon traditional character and plot development.

  13. #13 JM
    July 6, 2009

    I don’t know about the naming of quarks. Coincidentally, I was having a discussion about sub-atomic physics today with a civilian while having a smoke outside – as you do.

    The guy said he could never understand the ‘spin’ stuff of quantum mechanics and while explaining quantization, in an all-guys-together-round-the-water-cooler fashion, I ventured the opinion that physical intuition disappears on that small scale and really doesn’t help very much anymore.

    I went on to say that I thought the reason for using names like ‘charm’ and ‘strange’ was because physical analogies became positively misleading at the quark scale.

    That’s my guess anyway.

  14. #14 BAllanJ
    July 6, 2009

    Which is why everyone’s favorite unit of force is a Barn-yard-atmosphere.

    Hmmm.. wouldn’t that be a unit of energy? area x length x (force / area) = force x length

  15. #15 Matt Springer
    July 6, 2009

    You think you’re joking Abby, but I forgot to mention penguin diagrams

  16. #16 ppnl
    July 6, 2009

    “There was an abortive attempt to name the next two quarks “truth” and “beauty” but I like to think the earth opened and swallowed whoever proposed that and their graduate students got the message and renamed them to the marginally more sedate “top” and “bottom” quarks.”

    Thats just great. So instead of searching for naked beauty physicists are searching for bare bottom.

  17. #17 Steve
    July 6, 2009

    And let’s not forget the Smoot! (Although it’s more frat-boy than cute.)

  18. #18 CCPhysicist
    July 6, 2009

    First, that report you get on water quality (we get one also, and I wonder if yours wasted more money on glitz than ours did) is produced according to EPA rules. I’d guess they use “mho” because the regulations haven’t been updated since the siemens unit was added in 1971. Anyone know how to find out?

    Second, why do you think it is cool to celebrate intellectual laziness? Don’t they teach you young whippersnappers any physics history? And even if they don’t, don’t you have any intellectual curiosity about the two theories (QED and QCD) that do such a magnificent job describing physics from 1 nm down to 1 am? For quarks, I recommend the book “Second Creation”. First rate presentation of both the history and the physics of atomic and particle physics starting back in their “stamp collecting” days.

    The quark name was invented, not discovered by reading a novel. He was looking for a spelling that matched how he thought it should sound, and came up with quark and a citation that is worth reading in its own right. (You don’t see too many Nobel-worthy TWO page papers these days.) Impressively, Wiki gets this story completely correct, so you could read it instead. But I still recommend Close’s book for the combination of physics and history.

    Strangeness was invented first because, well, Kaons *were* strange! The quantum number of Strangeness was invented as a post hoc explanation for their slow decay. Associating a quark with this value was a brilliant guess that was not widely accepted by the HEP community until after the November 1974 discovery of charmonium. Charm was a prediction, significant enough that particle physicist today will go looking for anything a theorist tells them might be out there. Although not many will admit it today, most did not take the quark model, let alone charm, seriously. “The Second Creation” tells the story of a meeting in April where a then-prominent theorist summarized the contempt those present had for the “charming” idea presented by Glashow. In print!

    An earlier correspondent was partly correct but missed the barn. My main reason for elaborating is that you would have avoided any confusion if you had used standard SI units rather than that “trillionth of a trillionth of a square centimeter” nonsense. The barn is 100 fm^2. (Since a barn is pretty big for most reactions, we tend to use the millibarn where 1 fm^2 = 10 mb.) The radius of uranium is about 6 fm, so U has an area of a bit more than a barn. That is an easy way to remember the factor of 100.

    What Winter Toad seems to be thinking about is that the name was coined for reactions where the “cross section” (an effective area that describes the probability of a reaction taking place) was around 1000 barns. The probability of slow neutrons getting captured by uranium is a thousand times bigger than mere size (even including a 1 fm range for the strong interaction) can explain, so those reactions were described as being as easy as hitting the broad side of a barn. The name stuck because it made sense.

    The reason for the large reaction rate is that the wave function for the resonant compound state is much bigger than the nucleus and a slow neutron has a really long wavelength that diffracts and interacts with that resonance to enhance the capture rate. Basic wave mechanics: resonance shows up from sea shells to nuclear fission.

    PS – The femtometer was named so that nuclear physicists could still say “fermi” when they see fm. Until f was added to the prefix collection, the unit used for length in nuclear physics was F for Enrico Fermi. I have no idea how long they hunted for a word that would justify using f for a power of negative fifteen.

  19. #19 BlackGriffen
    July 6, 2009

    I’m not sure who first came up with it off the top of my head, but up and down got their names from the analogy between something called isospin symmetry and spin. Strange likely gets the name from the fact that strangeness was discovered before quarks were. Strange particles were called that because, IIRC, such particles had an unusually long lifetime compared with how abundantly they were created.

    If Wikipedia is to be believed, I’m right: http://en.wikipedia.org/wiki/Isospin , http://en.wikipedia.org/wiki/Strangeness_(particle_physics)

    The other problem with truth and beauty is that they’re not roughly antonyms like the other pairs are.

  20. #20 Eric Lund
    July 7, 2009

    I have no idea how long they hunted for a word that would justify using f for a power of negative fifteen.

    Pretty much any Germanic language would have done. The official story I heard long ago is that “femto” was derived from the Danish word for “fifteen” (and similarly, “atto” came from the Danish word for “eighteen”). Using Danish would have been a very indirect homage to Niels Bohr; I can’t think offhand of another reason for choosing Danish.

  21. #21 Isis the Scientist
    July 7, 2009

    It’s hot things, Matt. I like hot things.

    Ok, I probably like cute things too and you, my friend, are absolutely adorable! I do not like, however, the tale that JAK stands for “just another kinase” because people were tired of naming kinases.

  22. #22 Paul Camp
    July 19, 2009

    According to Gell-Mann, the term quark comes from the sound ducks make. Only the spelling comes from Finnegan’s Wake. For a while, he was going to write a paper on kworks. He had the sound before he had the spelling.

    Up and Down come from the fact that they are the up and down components of an isospin doublet. Strange is strange because it was discovered in particles that decayed strangely slowly. Top and bottom were the logical complements of up and down. Charm is pretty arbitrary but I guess could be considered sort of the opposite of strange.

    Finnegan’s Wake does not have a plot because it is about a dream and dreams don’t have plots. It has plenty of characters, though. There is the river, Anna Livia Plurabelle. There is Finnegan, who is brought back to life through the virtues of being splashed with whiskey (etymology, from the Irish uisge beatha = water of life). There is even you (and me and everybody else for that matter), Humphrey Chimpden Earwicker (= HCE = Here Comes Everybody).

    Your hero, James Clerk Maxwell, considered himself a bit of a poet. That’s aces for cuteness. His best known work is about rigid body motion, called Rigid Body Sings. It is written to the tune of Robert Burns’ Comin’ Through the Rye. Witness:

    Gin a body meet a body
    Flyin’ through the air.
    Gin a body hit a body,
    Will it fly? And where?
    Ilka impact has its measure,
    Ne’er a ane hae I,
    Yet a’ the lads they measure me,
    Or, at least, they try.

    Gin a body meet a body
    Altogether free,
    How they travel afterwards
    We do not always see.
    Ilka problem has its method
    By analytics high;
    For me, I ken na ane o’ them,
    But what the waur am I?

    (Scottish translation: “gin” = if “ilka” = every “ane” = one “hae” = have “a’ ” = all “ken” = know “waur” = worse)

  23. #23 Eric
    September 16, 2009

    The names of quarks and the like are nothing compared to some of the newer hypothetical particles. Supersymmetry, of course, has the convention of naming the SUSY partners of fermions (sfermions) by prefixing the fermion names with ‘s’, and replacing the ‘on’ in the boson names with ‘ino’; this leads to squarks, Winos, etc.
    There was a bit of a to-do amongst the particle theorists a year or so ago about “unparticles”.
    And one of the final straws in my decision to give up on skimming the hep-th arxiv regularly was a paper about pretzelosity functions.

  24. #24 GP
    September 16, 2009

    My particle physics prof last year still used the terms “truth” and “beauty”. If a particle state contained a top quark (more specifically, its top quantum number was not zero), for example, he would say “it has truth”, and similarly for “having beauty”. I prefer looking for truth and beauty.

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