Monthly Archives: July 2008

Did I Read That Right?

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This is the kind of post I start reading, and I begin to furrow my eyebrows as phrases and sentences pop up that don’t seem right or are obviously wrong. I though it was just bad science journalism, but realized it’s a rant-y agenda piece, with the supposed “science” reporting as a setup.

Superfluids, BECs and Bosenovas: The Ultimate Experiment

It starts off OK, giving some history, but then there was

Bosons are force carriers like photons of light and fermions are the matter we can touch.

Force carriers are bosons, but not all bosons are force carriers (universal affirmatives can only be partially converted, quoth the logician) — you can construct bosonic systems from an even number of fermions. Bosons have integral spin angular momentum, and fermions have half-integral spin, and the statistics that describe their behavior is different. An attempt to bridge the gap between science and a lay explanation that fails because it’s scientifically incorrect.

[helium is] produced by nuclear decay, as from radium and polonium, dangerous alpha radiation releasing, in fact bare nuclei of helium that eventually pick up electrons and form stable helium isotopes.

Here’s a journalistic archaeologism (it’s certainly not neo-) dangerous radiation. Nuclear radiation in invariably dangerous. Actually alpha radiation is pretty much harmless as an external dose, as it deposits its energy in a very short distance, so it doesn’t tend to penetrate even a layer of dead skin. The source is dangerous when ingested or inhaled. But the Helium nucleus is already stable (it doesn’t decay) even before it picks up the electrons — that makes it electrically neutral, not stable.

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The End of Theory. Not.

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A couple days back, Chris Anderson at Wired posted some junk about large volumes of data making the scientific method obsolete, misapplying George Box’s quote, “All models are wrong, but some are useful.” I was a little too distracted to respond, but it didn’t exactly escape the notice of the science and skeptic blog-o-icosahedron.

Bee over at Backreaction responds. Several links to other responses at the end.
Update: Good Math Bad Math reacts as well

Wear This Ribbon if You Support (Bad) Astronomy

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But if you can, since it’s 60 LY across, don’t ask me if your butt looks big.

Banner yet wave

[A] ribbon of gas, compressed and glowing due to a shock wave that slammed into it. The shock came from Supernova 1006, a star that detonated 7000 light years away from us. This was not a massive star that exploded, but a low-mass white dwarf, the dense core left over when a star like the Sun runs out of fuel. Still, the forces are roughly the same, with a titanic explosion ripping the star apart and creating eerie, unearthly beauty even in death.

The Camera Adds Ten pounds

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How many cameras are you wearing? (Chandler, to Monica)

candid camera, over at Cocktail Party Physics.

Richmond’s main hypothesis, however, was that the effect stems from the fact that the camera only has one “eye” (i.e., the lens), whereas human beings have two eyes, roughly 7 to 8 centimeters apart. The camera, it seems, lacks depth perception. The result is a kind of “flattening” effect that can make objects seem wider in photographs.

In This Corner, Wearing the Red Trunks . . .

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Particle and wave descriptions of light, duking it out in the early 19th century. What a drag: Arago’s Experiment (1810) over at Skulls in the Stars.

Before 1800, most scientists were proponents of the so-called corpuscular theory of light propagation. In this view, which was championed and solidified by Isaac Newton in his 1704 book Opticks, held that light consisted of a stream of particles. Newton explicitly argued against the wave theory of light and (seemingly) refuted arguments by early wave theory proponents such as Christiaan Huygens. Newton’s arguments, and his personal gravitas, left his particle theory mostly unchallenged until the early 1800s.

Shove Off

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The other day Matt over at Built on Facts had an interesting post, “Pushing Things in Space.” And while it’s rocket science, it’s not really rocket science. It’s Newton’s Third Law in action (and reaction), which is first-semester physics.

There is a lovely scene where the titular robot [Wall-E] uses a fire extinguisher to propel himself through the vacuum of space. There’s no sense in critiquing the physics of a gentle animated film, but it gives us an opportunity to talk about the principal challenge of moving about in space – there’s nothing to push against. On earth you push against the ground with your feet while walking, or with your tires when driving. If you’re in an airplane, the propellers or jet engines pull in still air in front of the plane and push it out the back at high speed. Boats do the same thing with water. It’s just Newton’s laws in action.

Down in the comments, CCPhysicist, aka Dr. Pion, has the real content I want to dissect.

Your remark, “the principal challenge of moving about in space – there’s nothing to push against”, is false. The statement “If you want to push against something, you’ll have to bring it with you” is closer, but still conveys a false concept common in students.

Pushing on the ground does not make you move. It is the ground pushing on you that changes your motion.

I don’t think the statement is false. I think it’s easily misconstrued and is often found to be confusing from the perspective of a beginning student or a reporter. It reminds me of that famous quote that appeared in the New York Times years ago, critiquing Robert Goddard

That Professor Goddard with his ‘chair’ in Clark College and the countenancing of the Smithsonian Institution does not know the relation of action to reaction, and of the need to have something better than a vacuum against which to react–to say that would be absurd. Of course, he only seems to lack the knowledge ladled out daily in high schools.

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He May Be On to Something

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This Einstein guy, that is.

In unique stellar laboratory, Einstein’s theory passes strict, new test

Precession of binary neutron stars.

Studies of other pulsars in binary systems had indicated that such wobbling occurred, but could not produce precise measurements of the amount of wobbling.

“Measuring the amount of wobbling is what tests the details of Einstein’s theory and gives a benchmark that any alternative gravitational theories must meet,” said Scott Ransom of the National Radio Astronomy Observatory.

The eclipses allowed the astronomers to pin down the geometry of the double-pulsar system and track changes in the orientation of the spin axis of one of them. As one pulsar’s spin axis slowly moved, the pattern of signal blockages as the other passed behind it also changed. The signal from the pulsar in back is absorbed by the ionized gas in the other’s magnetosphere.

Random Nonphysics Post

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Coffee Grounds Perk up Compost Pile With Nitrogen

About 2 percent nitrogen by volume, used coffee grounds can be a safe substitute for nitrogen-rich manure in the compost pile, explained Cindy Wise, coordinator of the compost specialist program at the Lane County office of the Oregon State University Extension Service.

“A lot of people don’t want to use manure because of concerns about pathogens,” said Wise.

Contrary to popular belief, coffee grounds are not acidic. After brewing, the grounds are close to pH neutral, between 6.5 and 6.8. The acid in the beans is mostly water-soluble, so it leaches into the coffee we drink.

Compost specialist program? Must . . . refrain from . . . making joke . . . about shitty education . . .