goodmath

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December 12, 2008
Elizabeth and the Catapult, "Golden Ink": a mellow track from a very good NY area band. This really isn't one of my favorites of their songs. It's rather on the dull side. Miles Davis, "Ray's Idea": Miles is one of the great geniuses of the 20th century. What more need be said? Do Make Say Think…
December 10, 2008
So, why math? The short version of the answer is remarkably simple: math provides a tool where you can, without ambiguity, prove that something is true or false. I'll get back to that - but first, I'm going to make a quick diversion, to help you understand my basic viewpoint on things. This…
December 7, 2008
Technorati Tags: ddftw, bozos,markcc-screwups So, as I said in the edit to my previous post about the wind-driven cart, I seriously blew it. The folks who pointed out the similarity of the cart to a tacking sailboat were absolutely correct. The guys who built this cart, and recorded the demo were…
December 5, 2008
In case anyone's interested, I'm currently fooling around with Twitter. If you're interested, I'm user-id MarkCC. Feel free to ping me if you've got an interesting twitter feed that you think would interest me; I'm still building up my list. Eventually, if I find it useful, I'll put a Twitter…
December 5, 2008
It's just been a week for metric errors. Via Media Matters comes an impressive list of stories in the media about the automobile companies financial problems, where they cite labor costs as a major issue. So far, so good. But in virtually every story about this, you'll find a statement along the…
December 3, 2008
(NOTE: It appears that I really blew it with this one. I'm the bozo in this story. After lots of discussion, a few equations, and a bunch of time scribbling on paper, I'm convinced that I got this one wrong in a big way. No excuses; I should have done the analysis much more carefully before posting…
December 1, 2008
One of the blogs I read regularly is Ben Goldacre's "Bad Science". I recommend it highly. (Which reminds me that I really need to find some time to update my blogroll!) In saturday's entry, he discussed a BBC Radio documentary that described how Britain is becoming a much more welcoming place for…
December 1, 2008
Technorati Tags: cryptography, public-key, encryption, RSA, asymmetric encryption The most successful public key cryptosystem in use today is RSA - named for its inventors Rivest, Shamir, and Adleman. I first learned about RSA in grad school from one of my professors, Errol Lloyd, who was one of…
November 24, 2008
Technorati Tags: scale, computation, information Since people know I work for Google, I get lots of mail from folks with odd questions, or with complaints about some Google policy, or questions about the way that Google does some particular thing. Obviously, I can't answer questions about Google…
November 20, 2008
I've been trying for a couple of weeks to put together a couple of interesting posts on the cryptographic modes of operation for confidentiality and integrity, and I just can't do it. I'm finding it boring to write about, and if it bores me to write it, I know there's no way that it's going to be…
November 14, 2008
Hawkwind, "Masters of the Universe": Great bit from the early days of psychadelic/progressive rock. I've got recordings of both the live and the studio versions, and I vastly prefer the studio. Peter Gabriel, "The Family and the Fishing Net": This is just a magnificent piece of music. I love pretty…
November 13, 2008
As long time readers of this blog know, one of the things that drive me crazy - in fact, one of the things that led me to start this blog - is the rampant innumeracy of our society. The vast majority of Americans have no real knowledge or comprehension of numbers or mathematics, and what makes…
November 11, 2008
It's always amusing to wander over to the Discovery Institute's blogs, and see what kind of nonsense they're spouting today. So, today, as I'm feeling like steamed crap, I took a wander over. And what did I find? High grade, low-content rubbish from my old buddy, Casey Luskin. Luskin is,…
November 7, 2008
(Note: I've changed the transliteration of the name of the dish since the original version of the post. I think it's now the correct pinyin transliteration. Please correct me in the comments if you know, and it's still wrong.) Today you get the recipe for one of my very favorite dishes. Since I…
November 5, 2008
Sorry about the abrupt end to the liveblogging last night; Firefox crashed, and CoverItLive wouldn't let me log back in as the moderator. Anyway, it's a good day to be a liberal. As you all know by now, it was Obama in an absolute landslide. He won by a huge margin in the electoral vote, and by a…
November 4, 2008
I'm going to be liveblogging the elections here starting at 7pm. I'll be doing my best to track the results as they come in, and what they mean. Feel free to come join in.
October 29, 2008
Once again, please don't forget about our DonorsChoose drive! Please click in the panel to you left, and go make a donation to help schools get the supplies they need to be able to teach math! Most people must have heard by now that about a week ago, T-mobile released the first Android based…
October 28, 2008
Before I get to the meat of the post, I want to remind you that our DonorsChoose drive is ending in just a couple of days! A small number of readers have made extremely generous contributions, which is very gratifying. (One person has even taken me up on my offer of letting donors choose topics.)…
October 24, 2008
In my last cryptography post, I wrote about using message authentication codes (MACs) as a way of guaranteeing message integrity. To review briefly, most ciphers are designed to provide message confidentiality - which means that no one but the sender and the intended receiver can see the plain-…
October 23, 2008
So, the financial questions keep coming. I'm avoiding a lot of them, because (A) they bore me, and (B) I'm really not the right person to ask. I try to stay out of this stuff unless I have some clue of what I'm talking about. Rest assured, I'm not spending all of my blogging time on this; I've got…
October 14, 2008
This is just a short gripe at the NYT, and a href="http://www.nytimes.com/interactive/2008/10/14/opinion/20081014_OPCHART.html">feature that they included in today's Op-Ed section. It purports to compare how the economy does under democratic versus republican administrations. They claim…
October 13, 2008
Writing this blog, I get lots of email. One of the things that I get over and over again is a particular kind of cluelessness about the idea of infinity. I get the same basic kind of stupid flames in a lot of different forms: arguments about Cantor's diagonalization; arguments about calculus (…
October 10, 2008
This is a recipe I created just a couple of weeks ago. I saw a beautiful Angus beef flank steak on sale, and wanted to find something to do with it. I came up with this idea of stuffing it. Amusingly, the day after it, a recipe appeared in the New York Times food section for a stuffed flank steak…
October 7, 2008
Today the 2008 Nobel Prize winners were announced for physics. It was given to three physicists who described something called symmetry breaking. Since most people don't know what symmetry breaking is, but people remember me writing about group theory and symmetry, I've been getting questions…
October 6, 2008
I don't have a lot of time to write; I'm having my fifth (I think) upper endoscopy done tomorrow, which means that the day's going to be a wash; and Yom Kippur is thursday, and I need to cook, so between the personal crap and work, I'm not going to have much time for blogging. So I'm trying to…
October 3, 2008
Don't forget to go and donate some money to schools through our DonorsChoose challenge. Seriously - throw them a couple of bucks. It doesn't need to be much. There are around three thousand people per day who read this blog; if you each contribute $5, it would more than pay to fully fund every…
October 2, 2008
Now, we're finally reaching the point where the block-cipher stuff gets really fun: block cryptanalysis. As I've explained before, the key properties of a really good encryption system are: It's easy to compute the ciphertext given the plaintext and the key; It's easy to compute the plaintext…
October 1, 2008
Every year at ScienceBlogs, we do a charity drive forDonorsChoose.org. If you haven't heard of them, DonorsChoose is a charity that takes proposals from schoolteachers, and lets people pick specific proposals to donate money to. We run our charity challenge through the month of October. For…
September 25, 2008
Ok, another batch of questions have come in, all variants on the same theme. The question is, if mortgages are at the root of the current economic disaster, how can it possibly result in close to a trillion dollars worth of losses? It definitely seems strange, on two different levels. On an…
September 23, 2008
There is at least a little bit of interesting bath math to learn from in the whole financial mess going on now. A couple of commenters beat me to it, but I'll go ahead and write about it anyway. One of the big questions that comes up again and again is: how did they get away with this? How could…