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drbaskin

HN member
Joined
Mon, Feb 11, 2008, 8:35 PM UTC
HN karma
132
Public activity
47 items

About drbaskin

I can be reached at dbaskin at math dot northwestern dot edu

Recent public activity

  1. comment
    Comment #6840534

    A minor nitpick: It was Andrew Wiles who proved Fermat's last theorem. Andre Weil was another incredible mathematician (responsible for, among many other things, the celebrated Wei…

  2. comment
    Comment #6471358

    I'm sorry to be so pedantic, but your math doesn't seem quite right. Should it instead be (1/100,000 chance of burning down each year) * ($200,000 cost if it does) = $2 per near ex…

  3. comment
    Comment #5475340

    This property of Piedmont is not even unique within the Bay Area! Fremont (the fourth-largest city in the Bay Area) has an enclave of its own, Newark, which is its own city yet com…

  4. comment
    Comment #4794532

    I use it for my weekly to-do list (since it then syncs across all computers and my phone), and it is a convenient way for me to keep track of my different projects. I type up a sho…

  5. comment
    Comment #4476183

    To belabor the point: Keeping one of the prices fixed, you should prefer that it be 20 percent more expensive on the weekend. Assume for example that the price on Saturday is $10 a…

  6. comment
    Comment #3425743

    If you're handy with simple algebra (and can remember that the derivative of x^2 is 2x) then you can remember the picture. If f(x) = x^2 - N, then you're looking for the (positive)…

  7. comment
    Comment #3350021

    Just to nitpick a bit -- your final three numbers add to 110, not 100. Perhaps you meant 49/31/20? I point it out only because 49/31/30 seemed too good to be true.

  8. comment
    Comment #3150416

    Or simple contraposition :-P Please correct me if I am wrong, but if the relevant part of the article is "I do not have insurance, so it is important that I maintain my health", th…

  9. comment
    Comment #2954550

    The 30% profit margin sometimes also signals that there are high barriers to entry. (You already mention what I think is the big one: accreditation.)

  10. comment
    Comment #2860391

    I haven't read Smolin's paper, so I'm not sure exactly what this article is getting at. Is he suggesting that there should be a different connection (i.e., not the Levi-Civita one)…

  11. comment
    Comment #2705441

    I'm sorry I wasn't more clear, but your interpretation is what I meant. Per your rule of thumb, seeing \tau should suggest that it has to do with circles or polar coordinates, and …

  12. comment
    Comment #2705294

    I'm not a big fan of introducing a new constant (though I believe \pi should have been 2\pi), but I love thinking of the integral you wrote down as \sqrt{\tau / 2} because then the…

  13. comment
    Comment #2544468

    You should never end a sentence with a preposition. The mathematician Paul Halmos loved issues like these and once constructed a sentence that ends in five prepositions: "What did …

  14. comment
    Comment #2511800

    I'm having trouble determining whether you are serious, but I suspect the original poster was referring to reddit's programming community.

  15. comment
    Comment #2469289

    I was aware of the group structure of the Rubik's cube (it is, after all, a subgroup of the permutation group on 54 elements), but apparently I had never given it much thought beyo…

  16. comment
    Comment #2464326

    Oh, fair enough! That's a fun example.

  17. comment
    Comment #2463146

    I don't follow -- what is the structure being preserved in this example?

  18. comment
    Comment #2459807

    I'm assuming you want non-trivial examples of non-bijective homomorphisms, but you can create a trivial one using the <= relation: Consider the two element set {0, 1} and the funct…

  19. comment
    Comment #2415257

    The a-ha answer still works, but the orignal answer given has you sum 2^(d-k) from k =0 to d, so in this example would be 2^1 + 2^0, suggesting that you would need 3 games to deter…

  20. comment
    Comment #2415118

    Nobody, but it was implicit in the solution proffered by the post I replied to. If the game they are playing has 5623 participants with one winner and 5622 losers, you only need a …

  21. comment
    Comment #2413408

    "If you had 5,623 participants in a tournament, how many games would need to be played to determine the winner?" Let d = Log_2 N. Sum 2^(d-k) for k = 0 ... d The a-ha solution to t…

  22. comment
    Comment #2350124

    I don't know whether this is the Lorenz they are referring to, but there was another Lorenz who worked in optics. http://en.wikipedia.org/wiki/Ludvig_Lorenz In fact, there is a Lor…

  23. comment
    Comment #2329657

    It's only somewhat related, but This Week's Finds in Mathematical Physics #234 discusses some of the math behind music theory. It's a nice article if you're familiar with basic gro…

  24. comment
    Comment #2325896

    I'm confused by your statement -- in the quaternions, i, j, and k are all square roots of -1.

  25. comment
    Comment #2251559

    I have great personal affinity for Texas but am having trouble coming up with a list of half a dozen top notch universities. I can come up with three (UT, TAMU, Rice) and a few mor…