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mark-t

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I'm a graduate student in mathematics at UCSD, studying Combinatorics. I also work on open source projects, such as fluxbox, and web applications, such as http://www.nationstates.net/ and http://math2.org/mmb/ . I'm not particularly interested in being an entrepreneur, but I'm also not particularly interested in being an employee, so we'll see. My website is http://mark.tiefenbruck.org/ -- you can find my contact information there, since I don't necessarily trust the email field here.

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I've never come across a keypad lock that would be vulnerable to this. You either have to press # at the end of the code, or the codes are significantly longer than 4 digits. Of course, even in the first category, entering 24 codes (50% chance of entering 12 or fewer) isn't a huge barrier once you know the four digits.

[dead] 17 years ago

I use Google Gears, so I can still access all of my mail. I'm sending e-mails from a mail server on my laptop, but I could just as easily use a different e-mail service while gmail is down. Yes, Google is a big company with lots of technical prowess, but you can't reasonably expect 100% uptime. If it's that important to you, you should have a backup plan.

Nope. I'm well aware that people still study analysis. I just meant that one doesn't necessarily need to learn calculus before taking the plunge into serious mathematics. Even in analysis, there's quite a bit you can do without knowing the stuff from a standard calculus class (though it certainly helps).

That post does not contain any advice. It contains facts, none of which were contradicted by your post (a typical property of facts). I never told him not to study calculus. Given our current education system, that would be impossible anyway. I guided him more toward real analysis and suggested some other areas of math that might interest him. Since his only background is high school math, I felt it would be best to introduce him to something where proofs play a central role. If he can't stand that, then he probably shouldn't go into math.

I'm aware of their applications; by "practically", I meant "almost". There are certainly compelling uses for number theory and combinatorics (though I'm not convinced the study of algorithms is one of them), but they're nothing compared to calculus.

No. Many pure math classes require no (or very little) calculus. Abstract algebra, number theory, combinatorics, and graph theory certainly fall into this category. Topology does, too, depending on which area you study and what you consider calculus. Sure, there are obviously fields that do rely heavily on calculus, as well as certain branches in the above fields, but my point was that it's nowhere near universally needed. I'm a graduate student at UCSD, and I can't remember the last time I used calculus in my research.

Putnam problems are not considerably harder than AIME problems, and AIME is definitely the next step from AMC12. Anybody who can solve a few AIME problems can certainly solve A1 on the Putnam of almost every year.

To be honest, calculus isn't that important for mathematicians, but if you want to study mathematics seriously, I'd suggest picking up a rigorous text like Rudin's or Apostol's. It will be difficult. You'll have to read most of it several times. That's perfectly fine; the point is that it will help you learn to think like a mathematician does.

Now, on the other hand, linear algebra is almost universally important and is probably easier for a programmer to grasp. I would also suggest picking up a Number Theory or Combinatorics text; they're practically useless, but they're fun and interesting, they'll give you a better idea of what mathematicians do, and you don't need much education to get into them.

My usual advice for building skills is to work on contest problems. See if you can find some AMC12 problems. If those are too easy, you can work your way up. AIME and Putnam would be good next steps (those can be found here: http://web.archive.org/web/20080205091131/http://www.kalva.d... ).

I'm not willing to concede his point yet, but even if he's right, this should be implemented by the browser, not the website. And if you consider taking his advice, I suggest masking the password as soon as the input field loses focus.

Me too, but I use more like 20 minutes per month. (Seriously, who needs a phone? That's what the internet is for.) The great part is that I can buy $10 worth of minutes at the end of the year, and all my minutes last another year. So, after four years or so, I will have paid maybe $160 including the phone. You can't come close to that kind of deal with any other provider.

What You Can't Say 17 years ago

I agree, up to perhaps a log-log scale. My grammar isn't likely to be significantly better in 30 years. However, when comparing among groups with similar English experience, grammar is likely to have a reasonable correlation with well-structured arguments. Also, the amount of time since learning English is not under your control; adherence to the rules of grammar is.

What You Can't Say 17 years ago

> ah right, judging someone from grammar is a very rational thing to do

I think you just turned "rational" into a label. Apart from your attempt at sarcasm, this statement is probably true. Like it or not, your ability to structure sentences reflects your ability to structure thoughts.

What You Can't Say 17 years ago

Read the notes: http://www.paulgraham.com/saynotes.html

[15] By this I mean you'd have to become a professional controversialist, not that Noam Chomsky's opinions = what you can't say. If you actually said the things you can't say, you'd shock conservatives and liberals about equally-- just as, if you went back to Victorian England in a time machine, your ideas would shock Whigs and Tories about equally.

Downtown San Diego is a long trip for nightlife. Most students probably won't have a car (parking is ~$600), so it'll be over an hour on the 30 each way (150 doesn't run at night). I don't even know how to get to PB by bus. My friends who live there all drive or bike to school.

Full disclosure: I'm a math PhD student at UCSD.

UCLA is probably better overall for math, but UCSD is better for graph theory and combinatorics in general, the most likely kind of math CS students would be interested in.

In my opinion, there will be very little difference between the schools in terms of education, quality of peers, or job potential upon graduation. I would choose based on which location I like better. Personally, I hate LA, although UCLA's campus is beautiful. There's probably a lot more to do there, too, depending on what activities he enjoys.

UCSD has a great zoo, Sea World, and Lego Land nearby, but not much for drinking establishments. Many CS and math majors go to the pub on campus regularly; I haven't heard of anything else.

[dead] 17 years ago

It is spelled correctly. It's just not a word.

> Fourth, if web crawlers get hold of any URLs which exhibit side effects on GET, they will wreak havoc on your site.

Web accelerators, too, and those will not be controlled by robots.txt. I would definitely advise the OP to read the HTTP spec about the differences between POST and GET, or perhaps an introduction to RESTful web development.

I showed this article to a friend of mine who did a PhD in physics at Cambridge. Here's what he had to say:

The entanglement arguments against relativity are fairly silly. From that article, looks like Scientific American is going the way of the New Scientist. :( Absolutely no mention of Everett and his MWI (editor's note: multiple worlds interpretation) in the article I notice. Even though that's the most obviously straightforward way of keeping special relativity, locality, quantum mechanics and accounting for the Aspect experiment. Basically Bell's theorem that is supposed to prove non-locality makes a subtle assumption called "counter-factual definiteness", which implies among other things that experiments have definite outcomes. Obviously it's violated by MWI. Really it's only Bohmian mechanics that's non-local and arguably not consistent with SR. Though Bohm adherents often claim that Copenhagen must be non-local by Bell's theorem, they misunderstand the fact that the wavefunction in CI is really an epistemic device and wavefunction collapse isn't thought to be a genuine physical occurrence except by a very small minority. CI when viewed in this way doesn't satisfy counter-factual definiteness either.

[dead] 17 years ago

Agreed. Some of Coding Horror's material is certainly worthwhile. For example, I know I found out about the HttpOnly flag in cookies from him, and I'm pretty sure I've learned of some usability improvements from his articles as well. However, there are a lot of his articles that I don't think really belong on HN, but they end up here anyway.

I'm actually a bit suspicious that the following may be happening:

1) Karma-hungry users submit all of his articles as soon as they're posted without checking whether or not they've been submitted already.

2) Since submitting a page that's already been submitted results in an upvote, his articles make it to the front page and RSS feed without the usual oversight of people reading things in the new submissions list.

[dead] 17 years ago

Judging by the comments, I'm not missing much, but I refuse to read this until the author gets a spelling checker.

I upvote things that I think are more important for other people to read -- that is, if I think it should be displayed higher on the page.

I downvote things that I don't think other people should bother reading -- that is, if they're uninsightful, irrelevant, or somehow distasteful.

The vast majority of things I just leave alone.

I think the word karma itself is partly to blame. It makes you think you're rating whether the comment is good or bad, but the effect of the up/down arrows is merely to sort comments based on relative quality/value for people who view the thread after you. For a while, I've toyed with the idea of suggesting a new interface that asks users to sort comments, rather than upvote or downvote, but I haven't thoroughly thought about it.

I like it. Most things I play with a projector don't start with higher than 640x480 resolution, anyway, so the picture quality is actually quite good. It tends to get a little hot, which causes me to worry, even though I'm sure the engineers worked out all the details. The VGA cable is a bit finicky, and it's a little too short. It also came with an RCA connector.

I have a 3M MPro110. It's 640x480 (vs. 480x320) and about $350 (vs. $430). Also pocket-sized. I don't see the comparison.

> However, it is still very possible to develop good mathematical skills without a degree.

Absolutely. I don't think the degree is very useful for developing skills at all. I'm sure there are plenty who would disagree, but mathematics courses don't set a very high bar for how much you have to think about a topic. I learned more in the past month preparing for my algebra qual than I did during an entire year of an undergrad class at Northwestern (of course, I drew heavily on the basic knowledge I had).