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A Manchester scientist has come up with a mathematical formula to assess the perfection of the female derriere. “Dr Holmes said that Kylie Minogue, whose celebrated bottom relaunched her career with the help of a pair of hotpants, would almost certainly score a perfect 80.”
Fascinating thoughts on the future of science by Kevin Kelly. The sequence of recursive devices and triple blind experiments (“no one, not the subjects or the experimenters, will realize an experiment was going on until later”) were especially interesting.
Profile of Daniel Dennett, “Darwinian fundamentalist” and author of a new book that argues that “religion, chiefly Christianity, is itself a biologically evolved concept, and one that has outlived its usefulness”.
Collection of publicly available articles from The Best American Science and Nature Writing 2005. Good reading. (thx, robin)
Sociology study indicates that atheists are the least trusted group of people in America. “Researchers found that Americans rate atheists below Muslims, recent immigrants, homosexuals and other groups as ‘sharing their vision of American society.’ Americans are also least willing to let their children marry atheists.” Also, “those surveyed tended to view people who don’t believe in a god as the ‘ultimate self-interested actor who doesn’t care about anyone but themselves.’” (via dg)
The Edge has a transcript and an mp3 recording of an event called The Selfish Gene: Thirty Years On. The speakers include Daniel Dennett and Richard Dawkins.
Watched America’s Stone Age Explorers on PBS this evening, a summary of recent findings about who the first Americans were, where they came from, and when they arrived. Recent genetic and archeological evidence suggests they arrived earlier than generally accepted and may have originated from Europe rather than Asia.
20-year-long study shows that children who were whiny and insecure tend to grow up to be conservatives and “confident, resilient, self-reliant” children tend to grow up to be liberals. “He reasons that insecure kids look for the reassurance provided by tradition and authority, and find it in conservative politics. The more confident kids are eager to explore alternatives to the way things are, and find liberal politics more congenial.”
To Dr. David Hague, human pregnancy is a struggle between the fetus and mother. Evolutionarily speaking, the fetus “wants” as many resources as possible for itself while the mother “wants” to do what she can to spread her resources across as many children as possible. In theory, this is a cause of the many serious health problems surrounding pregnancy.
Update: Carl Zimmer has more about this on his blog.
Short Elizabeth Kolbert article on the conservative response to climate change. “The new argument making the rounds of conservative think tanks, like the National Center for Policy Analysis, and circulating through assorted sympathetic publications goes something like this: Yes, the planet may be warming up, but no one can be sure of why, and, in any case, it doesn’t matter — let’s stop quibbling about the causes of climate change and concentrate on dealing with the consequences.”
Jupiter is growing another big red spot. The gas giant has been told by solar system pals to “keep an eye on it” and “have it checked out” if it gets any bigger.
Pruned has collected some lovely petri dish scenes full of fractal patterns.
Billions and billions of bacterial landscape architects pruning — no less in environments poisoned with antibiotics — other bacterial landscape architects, dead or alive, to form dazzling arabesque parterres. The self-organizing embroidery of organisms in constant Darwinian mode.
More here. See also ferrofluid.
Justin reports on his family’s results of a neat project called the Geneographic Project, co-produced by National Geographic and IBM. If you purchase a testing kit, they’ll trace the specific genetic markers of your ancestors back to (possibly) our common African root.
An Antarctic project has detected the first neutrinos observed outside of a laboratory setting.
A Crash Course On Complexity, Emergence and Collective Intelligence.
Beautiful people commit less crime. “Other studies have shown that unattractive men and women are less likely to be hired, and that they earn less money, than the better-looking. Such inferior circumstances may steer some to crime, Mocan and Tekin suggest.”
Gamers show a “similar pattern of high performance in resisting irrelevant impulses” as bilingual people. “Maybe those kids who play video games and who are also bilingual will be the best of older adults at filtering out distractions.” (via sjb)
“In the late 20th Century, the northern hemisphere experienced its most widespread warmth for 1,200 years”. “The last 100 years is more striking than either [the Medieval Warm Period or Little Ice Age].”
Now that I’ve closed the comments on the question of the airplane and the conveyor belt, I’m still getting emails calling me an idiot for thinking that the plane will take off. Having believed that after first hearing the question and formulating several reasons reinforcing my belief, I can sympathize with that POV, but that doesn’t change the fact that I was initially wrong and that if you believe the plane won’t take off, you’re wrong too[1].
The only thing is, I’m not sure how to prove it to you if you don’t understand the problem and the physics involved. I guess I could urge you to read the question and answer again carefully. I could tell you that not only does the conveyor belt not keep the plane stationary with respect to the ground but it *can’t* keep that plane stationary with respect to the ground[2] and once you know that, of course it’ll take off. My pal Mouser has a Ph.d in Physics from MIT and he says the plane will take off:
The airplane would take off normally, with the wheels spinning twice as fast as normal and a *slight* reduction in acceleration due to added friction.
Is that enough to convince you?
[1] This situation reminds me of Richard Dawkins’ and Jerry Coyne’s assertion that “one side can be wrong”.
[2] The motion of the conveyor belt does nothing[3] to affect the movement of the plane when the plane is in motion…it doesn’t matter if it’s moving forward, backward, at 2 MPH, or at 400 MPH. If the plane were on castors that could spin freely from side to side as well as front to back, that treadmill could be spinning 100 MPH to the left and the plane would take off.
[3] Well, almost nothing. The friction of the turning wheels will slow things down a bit, but not enough to not make the plane take off. After all, the main function of the wheels of a plane is to provide a near-frictionless interface with the ground (or whatever the plane happens to be taking off from).
Robert Birnbaum interviews physicist Lisa Randall about string theory and science popularizers.
This question posed to Cecil at The Straight Dope has occupied most of my day today:
Here’s the original problem essentially as it was posed to us: “A plane is standing on a runway that can move (some sort of band conveyer). The plane moves in one direction, while the conveyer moves in the opposite direction. This conveyer has a control system that tracks the plane speed and tunes the speed of the conveyer to be exactly the same (but in the opposite direction). Can the plane take off?”
I’ll give you a few moments to think about that before discussing the answer…
…
…
…
Cecil says that the obvious answer — that the plane does not take off because it remains stationary relative to the ground and the air — is wrong. The plane, he says, can take off:
But of course cars and planes don’t work the same way. A car’s wheels are its means of propulsion—they push the road backwards (relatively speaking), and the car moves forward. In contrast, a plane’s wheels aren’t motorized; their purpose is to reduce friction during takeoff (and add it, by braking, when landing). What gets a plane moving are its propellers or jet turbines, which shove the air backward and thereby impel the plane forward. What the wheels, conveyor belt, etc, are up to is largely irrelevant. Let me repeat: Once the pilot fires up the engines, the plane moves forward at pretty much the usual speed relative to the ground—and more importantly the air—regardless of how fast the conveyor belt is moving backward. This generates lift on the wings, and the plane takes off. All the conveyor belt does is, as you correctly conclude, make the plane’s wheels spin madly.
After reading the question this morning and discussing it with Meg for, oh, about 3 hours on and off, I was convinced that Cecil was wrong. There’s no way that plane could take off. The conveyor belt keeps pace with the speed of the plane, which means the plane remains stationary from the POV of an observer on the ground, and therefore cannot lift off.
Then I read Cecil’s answer again this evening and I’ve changed my mind; I’m fairly certain he’s right. For a sufficiently long conveyor belt, that plane is taking off. It doesn’t matter what the conveyor belt is doing because the airplane’s energy is acting on the air, not the belt. I had better luck simplifying the problem like so: imagine instead of a plane, you’ve got a rocket with wheels sitting on that belt. When that rocket fires, it’s eventually going to rocket off the end of that belt…which means that it doesn’t remain stationary to the ground and if it had wings, it would fly.
What do you think? Can that plane take off?
See also Feynman’s submerged sprinkler problem and an old argument of Newton and Huygens: can you swim faster through water or syrup?
Update: Well, that got out of control in a hurry…almost 300 comments in about 16 hours. I had to delete a bunch of trolling comments and it’s not productive to keep going, so I closed it. Thanks for the, er, discussion and remember, the plane takes off. :)
Scientists find “lost world” of undiscovered animals in the Foja Mountains of western New Guinea. “Their finds included more than 20 new frogs, 4 butterflies and a number of plants, including 5 new palms and rhododendrons with the largest flowers on record.”
The world’s coolest parasite; it makes zombie cockroaches! When it wants to lay its eggs, the Ampulex compressa wasp stuns a cockroach, numbs its brain, steers it back to its nest, lays an egg inside it, and eventually a larvae forms, it lunches on the cockroach’s insides, and then hatches fully grown. Just…wow. (thx, tien)
Political party members’ brains get a rush from “ignoring information that’s contrary to their point of view”. “None of the circuits involved in conscious reasoning were particularly engaged. Essentially, it appears as if partisans twirl the cognitive kaleidoscope until they get the conclusions they want, and then they get massively reinforced for it, with the elimination of negative emotional states and activation of positive ones.”
Short (and a wee bit hostile) inteview with Daniel Dennett. “Nerve cells are very complicated mechanical systems. You take enough of those, and you put them together, and you get a soul.”
Giant jellyfish invade Japan STOP Creatures 2 meters wide and 450 pounds STOP Killing fish, fishing industry, and even humans STOP Run for your lives STOP
Recently discovered human remains suggest that metrosexuals lived in Iron Age Ireland. One man’s fingernails were manicured and his hands indicated he’d never done manual labor while the other wore hair gel imported from France and Spain. No word on if they wore their shirts tucked or untucked.
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