drbaskin

8 ms·

1.
by drbaskin 13y ago
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 Weil conjectures), but did not prove Fermat's last t
2.
by drbaskin 13y ago
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 expected damages?
3.
by drbaskin 13y ago
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 completely surrounded by Fremont.
4.
by drbaskin 14y ago
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 short summary for myself after meetings and I can also easily
5.
by drbaskin 14y ago
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 and the price on Tuesday is $8. It is then "20 percent chea
6.
by drbaskin 15y ago
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) zero of f. You take a succession of tangent lines and loo
7.
by drbaskin 15y ago
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.
by drbaskin 15y ago
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", then the contraposition would be "It is not important that I
9.
by drbaskin 15y ago
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.
by drbaskin 15y ago
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) on the cotangent bundle of spacetime or is it something mo
11.
by drbaskin 15y ago
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 the square root points to how to get the polar coordinates.
12.
by drbaskin 15y ago
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 answer practically tells you how to derive it! How to deriv
13.
by drbaskin 15y ago
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 you want to bring that book that I didn't want to be read to
14.
by drbaskin 15y ago
I'm having trouble determining whether you are serious, but I suspect the original poster was referring to reddit's programming community.
15.
by drbaskin 15y ago
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 beyond that. Thanks!
16.
by drbaskin 15y ago
Oh, fair enough! That's a fun example.
17.
by drbaskin 15y ago
I don't follow -- what is the structure being preserved in this example?
18.
by drbaskin 15y ago
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 function f from {0,1} to {0,1} so that f(0) = f(1) = 0. f pr
19.
by drbaskin 15y ago
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 determine the winner.
20.
by drbaskin 15y ago
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 single game!
21.
by drbaskin 15y ago
"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 this puzzle is to realize that every participant but one h
22.
by drbaskin 16y ago
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 Lorentz-Lorenz equation. Somewhat more confusingly, when yo
23.
by drbaskin 16y ago
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 group theory. http://math.ucr.edu/home/baez/week234.html
24.
by drbaskin 16y ago
I'm confused by your statement -- in the quaternions, i, j, and k are all square roots of -1.
25.
by drbaskin 16y ago
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 more if you set the bar a bit lower, but none of the these (ar
26.
by drbaskin 16y ago
The title of this post seems to be a reference to the famous paper of Wigner titled "The Unreasonable Effectiveness of Mathematics in the Physical Sciences." It is a very readable paper and I cannot recommend it highly enough. http://en.w
27.
by drbaskin 16y ago
I agree with you until your last sentence. Especially in upper division courses, the material is more complicated and problems that really test understanding are too ambitious for an exam. This means that if you want to see the student solv
28.
by drbaskin 16y ago
I'm sure that you have an implicit statement about the constants when you imply that O(log_{k}(|T|)) is an improvement over O(log_{2}(|T|)), but log_{2}(|T|) = {log_{k}(|T|)} / {log_{k} (2)}. Correct me if I'm wrong, but in terms of big-O
29.
by drbaskin 16y ago
I don't whether the error you introduced is intentional or not, but 120 * 0.8 = 96, not 106. Another way of thinking about this is that 1.2 * 0.8 = 0.96, so it is a four percent pay cut. (This is true for any situation like this and can be
30.
by drbaskin 16y ago
Not only are they dense, but they are "most" continuous functions! (For an appropriate interpretation of "most", of course)

More ›