jack

There's an old joke, biology is really physics, and physics is really maths. It's easy to extend this to a much longer totem pole, something like Politics->Sociology->Economics->Psychology->Physiology->Biology->Physics->Maths->Philosophy... etc. (It wraps round).

However, it occurs to me an equally valid way of phrasing it, but one which allows the smugness to gravitate to the other end of the spectrum, would be "Biology is physics which is too hard for physicists to solve. Physics is maths which is too hard for mathematicians to solve".

And there's a lot of truth in that. Mathematicians are disdainful that physicists use approximations (especially if they use them when they don't need to). But mostly, physicsts use approximations for things that can't be solved mathematically (eg. stuff with more than one hydrogen atom in). Both are completely necessary :)

Bah, I should post something about QI's analysis of urban legends and common misconceptions. I feel, not knowing the format, I was confused the first shows I saw.

The questionable fact in this case involved the original discovery of penicillin, was it Duchesne rather than Fleming? Conveniently wikipedia describes the discoveries of penicillin before Fleming.

No, seriously. The page entitled Discoveries_of_anti-bacterial_effects_of_penicillium_moulds_before_Fleming

The situation seems to be:

* Lots of people including ancient greeks and 19-century "Arab stable boys" were aware that some moulds cured saddle sores and other infections[1].
* Several scientists, including Lister and Pasteur tried penicillum mould out
* Duchesne may have been the first to really study it, but the Institut Pasteur didn't accept any of his work.
* Fleming independently rediscovered it, and was the first to isolate the active ingredient, penicillin.
* It's slightly more complicated than that.

Thus, the traditional myth is "Fleming discovered Penecilin" and the slightly more recent myth that "Fleming rediscovered it, but Duchesne discovered it first." The show presented the first of these as false, and the second as true, with a cut down version of the tale above.

However, knowing the format, I've a much better appreciation of why it works. When Fry says there'll be a round of obvious questions coming, and asks who discovered penicillin, and there's a pause, and Davies hesitates and buzzes[2], everyone knows he's going to say Fleming and it's going to be wrong. Fry knows it. He knows it. They know it. We know it. He just *can't resist*. And that's funny -- genuinely, it was hilarious.

Davies isn't exactly wrong. Certainly, Fleming did discover Penicillin, and only an incredibly precise level of pedantry would say that independently rediscovering it wasn't discovering it. However, the meta-story is that there's something more to the story, which Davies is genuinely ignorant of, and everyone knows that the score for the question really hangs on that, however precise.

But because this is implicit, someone watching is given the impression that "Fleming" is inherently a stupid or ignorant or incorrect answer to the question "Who discovered penicillin?" which is what's so offensive, and why I was so annoyed the first time I watched it.

I still think that's bad practice, to spread legends, but on the other hand the question last week wasn't actually indefensible, in that if Davies *had* said "50, of which 4 are commonwealths" he *would* have got a moral victory (whatever the score), and he lost points, not for knowing the correct answer, 50, but for not knowing the legend, which is implicitly the real question.

[1] I didn't know that. So apparently quantum leap was a lot more on target than I thought when the professor cures a plague by drinking distilled mould. Though I don't know if distilling would have made an orally-effective substance, it could do.
[2] Insofar as a buzzer calling "Hello, Sailor" is buzzing.

* I did some more brief cooking experiments. Coating raw spaghetti in oil or pesto didn't seem to make any difference.

* Any spaghetti can be brought into the mouth with a lip-over-lip and tongue action. Cooked spaghetti can be brought into the mouth keeping the mouth, cheeks, tongue and lips entirely stationary but pursed, and sucking. (It's quite distinctive, it goes slitherslitherfast and then the end waves forlornly and then smack.)

* But even dipped in oil, cooked spaghetti didn't seem to be sucked in. However, this is far from conclusive -- there's nothing to say the coating is enough to make the friction of the raw and cooked spaghetti strands the same. Or, for instance, perhaps raw spaghetti has a rough surface you can't make a good seal on.

* If anyone wants to settle this, the open questions are still:

1. An air-pressure explanation of why sucking a floppy object would work. (Discussion still going on in the first post, Lisa had thoughts I've yet to respond to.)
2. Are we agreed you can suck cooked spaghetti solely by air pressure, without any pushing from the lips and tongue?
3. Is the matter of not sucking raw spaghetti its friction, or its compressibility or what? This ought to be obvious, I'm sure, but I don't feel concluded yet.

http://www.straightdope.com/classics/a4_184.html

Straight dope asks "How can you suck a strand of spaghetti?" The question being, sucking a liquid, you create a vacuum in your mouth, and it's generally enough to say the pressure within the liquid is less than that in the mouth, so a force acts on the liquid in the straw. Sucking a solid object (eg. pencil), you can say the air pressure cancels out all over, except down the length.

But spaghetti is floppy. The air pressure on the *end* of the strand can't be relevant, because pushing their wouldn't force it into the mouth.

The answer doesn't seem very satisfactory. I'm sure it's something like, air pressure generally acts all over the surface, perpendicular to it, and this cancels out all over[1]. Except on a line through the part of the strand through the lips. So there's a force on that part, propagated down the strand to the next bend (where it acts sideways to the strand).

But I can't really put that into words (or symbols). Can anyone else provide a simple, satisfying description?

[1] May be hard to show, either by common sense or integrals, but we know it *does* because the net air pressure on a strand of spaghetti in midair (neglecting variations with height) is zero everywhere.