Tuesday, November 21, 2006

More links



  • Chad discusses some of the problems with intro physics classes. I pretty much agree with all that is said. There's much to cover, not much time to do it, and lectures aren't very effective. With that said, it seems to me the answer isn't to change how much is covered. The answer is to say "You want to be a science major? Well, handle it." There will be many who cannot. Within the confines of this, however, it would be nice to find out how to make lecture more effective (short of slowing things down).

  • Story out about a measurement of the spin of a distant black hole. I wish they would always have a link to the journal article at the heart of the story, but alas I have found it at the arxiv.org. The article points out that since black holes have no hair (and because we don't expect to find a charged hole), black holes that have actually been observed are described by just the mass and the spin. More importantly then, the mass of the black hole serves only to set a physical scale, but the spin of the black hole actually produces qualitatively different holes. I can't come up with a great analogy, but I suppose you could think of round balls. The radius simply sets the scale of the ball. To get a different kind of ball you've got to change the surface/feel to go from, say, a kickball to a basketball. Not the best analogy, but what the heck.

  • Why aren't spam filters better? I can recognize spam so easily. I can understand the filter having problems with new messages not seen by the filter, but I've marked otherwise identical messages as spam. Yet, it continues not recognizing these as spam. Furthermore, the filters have access to the internet, so can't they use information from elsewhere to confirm they're spam? I was pretty happy about a year ago, but it seems over the last six months or so, the filters just can't hack it.

  • A nice article at the NYT (free reg. reqd.) on the Mythbusters show.

4 comments:

Uncle Al said...

There is no fax spam because government and military faxes could not be excluded. There is no .gov or .mil spam and spammers are political contributors. Do you have ill will toward goverment?

Identity theft is immense in scale and injury. The law specifically targets the aggrieved, subjecting them to protracted loss and near-impossible rectification. It's good business.

If you want the problem removed then it must be suffered by those who do the removal.

CarlB said...

I have great sympathy for anyone teaching an intro physics course. The basic problem is that there is too much material and not enough semester hours.

The other departments concentrate their easiest material at the freshman class. Physics throws it all at them. It's hardly amazing that little of it sticks.

Politically, I see no solution. But I'd split the three semester course into about six semester, to be taken simultaneously by majors, and with each semester being a single subject.

As it is, the survivors tend to be people who can memorize lots of concepts without having any deep understanding of them (i.e. pre med students), rather than those who have to understand things deeply in order to understand them at all (i.e. next Einsteins).

I regularly run into smart people who thought Calculus was a breeze but choked on 1st year Physics.

Angry said...

Carlb: It is rare indeed that students at the introductory level will gain a deep understanding, but I don't think that relegates the survivors to rote memorizers. As for calculus, well, it is easy!

CarlB said...

Yes, it's not that all the survivors are rote memorizers. There are a lot of students who will learn it no matter how the material is taught.

And calculus is easy. So is clasical mechanics. If the introductory mathematics class covered elements of probability, logic, differential equations, discrete mathematics, abstract algebra, topology, analysis, and number theory, it would be just as much a disaster as the elementary physics classes.

But politically, I don't see a solution.