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  • The Kama Sutra (कामसूत्र) is an ancient Hindu text about sensory pleasure. Although it’s best known in English for its most risqué chapters, it also contains a list of sixty-four arts whose knowledge makes a person popular and attractive.

    1. Singing.
    2. Playing on musical instruments.
    3. Dancing.
    …
    28. A game, which consisted in repeating verses, and as one person finished, another person had to commence at once, repeating another verse, beginning with the same letter with which the last speaker’s verse ended, whoever failed to repeat was considered to have lost

    Kama Sutra, Chapter 3

    In modern times, the twenty-eighth art is primarily practiced by bored children on road trips and is known by many names like word chain or shiritori. I had no idea it was over 1700 years old!

    2024-09-25
  • [M]ost of the things we buy have to be paid for twice. There’s the first price, usually paid in dollars, just to gain possession of the desired thing, whatever it is: a book, a budgeting app, a unicycle, a bundle of kale. But then, in order to make use of the thing, you must also pay a second price. This is the effort and initiative required to gain its benefits, and it can be much higher than the first price.

    David Cain

    2023-08-25
  • Rubber duck problem solving describes the phenomenon where you realize the solution to a problem in the middle of explaining it to someone else. The name stems from apocryphal stories in which stumped engineers are advised to get help from inanimate objects, including a literal rubber duck.

    The technique works because communication forces us to arrange our thoughts and prevents us from taking shortcuts that would leave our audience behind. As one developer explains:

    When you force yourself to verbalize something, you take poorly formed mind-stuff and slot it into discretely packaged concepts (words) whose meanings are agreed upon by other humans. This alone adds an important layer of organization to your thinking by taking non-verbal soup and giving it shape.

    Joseph Pacheco

    2014-04-09
  • Paul Erdős is flanked by Kevin Bacon and the members of Black Sabbath

    A little while ago, I did some sleuthing to find out the Erdős number of Brian May, astrophysicist and guitarist from Queen. My travels led me to Timeblimp, who threw together three measures of professional collaboration to make a rather fun parlour game. Assuming that the people in your parlour are three kinds of nerds and enjoy long and complicated internet scavenger hunts. Which I am and I do.


    The game is to find a well-known person who has published academically, released a song, and been involved in a movie or TV show. Then, you play three versions of Six Degrees of Kevin Bacon: find a series of movies to connect them to prolific actor Kevin Bacon, a series of coauthored papers to connect them to the eccentric mathematician Paul Erdős, and a series of musical collaborations to get to Black Sabbath. Add up all the links and you get the Erdős-Bacon-Sabbath number.

    Brian Cox has an Erdős-Bacon-Sabbath number

    If anyone has an Erdős-Bacon-Sabbath number, Brian Cox is exactly the sort of person you might expect to have one. The keyboardist, particle physicist, and BBC science presenter is no more than 7+3+3 degrees of separation from the centers of the EBS graph.

    Sean from Timeblimp first suggested the possibility of Brian Cox having a well-defined Erdős-Bacon-Sabbath number, but to my knowledge nobody had worked out his Erdős number until now. I managed to find a path of length seven.

    Erdős numberResearcherCitation
    7Brian CoxHard colour singlet exchange at the Tevatron
    6Leif LönnbladSmall-x dipole evolution beyond the large Nc limit
    5Gösta GustafsonThe action-angle variables for the massless relativistic string in 1+1 dimensions
    4Bo SöderbergScaling laws for mode locking in circle maps
    3Boris ShraimanScaling theory for noisy period-doubling transitions to chaos
    2C Eugene WayneThe Euler-Bernoulli beam equation with boundary energy dissipation
    1Steven George KrantzIntersection graphs for families of balls in ℝn
    Paul Erdős

    The above connections use only papers with three coauthors or fewer. Cox has worked in gigantic collaborations like ATLAS, so it’s quite possible that there might be a shorter path.

    Brian Cox — not to be confused with the other Brian Cox — is three degrees of separation from Kevin Bacon through his many TV appearances, including cameos on Doctor Who.

    Bacon numberActorCredit
    3Brian CoxDoctor Who “The Power of Three”
    2Matt SmithCharlie Says
    1Sosie BaconStory of a Girl
    Kevin Bacon

    Brian Cox had a successful music career before finishing his PhD and also has a Sabbath number of three.

    Sabbath numberMusicianBand/Album
    3Brian CoxDare
    2Darren WhartonThin Lizzy
    1Tommy AldridgeSpeak of the Devil
    Ozzy OsbourneBlack Sabbath

    Aftermath

    After I published this post, someone brought it to the attention to none other than Brian Cox himself!

    A screenshot of a tweet by Brian Cox, reading "It has just been pointed out to me that I have an Erdős-Bacon-Sabbath number!!"

    The resulting hullabaloo led to the discovery of many other Erdős-Bacon-Sabbath numbers. Eventually, I retired from EBS research after realizing its flaws as a game and as a social construct.

    2012-06-24
  • Brian May playing a guitar back-to-back with Paul Erdős giving a lecture

    If you’ve heard of Erdős numbers, Erdős-Bacon numbers, and the fact that Queen lead guitarist Brian May has a PhD, you may have wondered whether Brian May has a well-defined Erdős number.

    As a matter of fact, he does! I traced down a collaboration path of length seven through a 1972 paper he published in Nature.


    Erdős numberResearcherCitation
    7Brian MayMgI emission in the night sky spectrum
    6T R HicksThe structure of NGC 7027
    5J P PhillipsQCD: quantum chromodynamic diffraction
    4K Golec-BiernatIntegrable Hamiltonian system in 2N dimensions
    3Th W RuijgrokOn the dynamics of a continuum spin system
    2C J ThompsonOn the mathematical mechanism of phase transition
    1Mark KacThe Gaussian law of errors in the theory of additive number theoretic functions
    Paul Erdős

    This beats the best previous attempt I found, a path of length eight through a popular science book cowritten by May. It gives him an Erdős-Bacon number of at most 10 (and an Erdős-Bacon-Sabbath number of at most 11).

    2009-10-18
© 2007–2025 Ross Churchley