Skeptophilia (skep-to-fil-i-a) (n.) - the love of logical thought, skepticism, and thinking critically. Being an exploration of the applications of skeptical thinking to the world at large, with periodic excursions into linguistics, music, politics, cryptozoology, and why people keep seeing the face of Jesus on grilled cheese sandwiches.

Saturday, June 8, 2024

Spin doctor

Yesterday's post, which featured a guy who claims he has revolutionized physics with a model starting from the axiom that 1 x 1 is actually equal to 2, prompted a long-time loyal reader of Skeptophilia to send me a link accompanied by the note, "Yeah, okay, Gordon, but what about this, huh?  What about this?"

The link was to the page of a guy named John Mandlbaur, a South African "investor and successful businessman" who at least admits up front that he is "not an academic."  This, when you start looking into his claims, is putting it mildly, because he is also claiming to have revolutionized physics, this time starting from the statement that the Law of Conservation of Angular Momentum is wrong.

At least he, unlike the guy in yesterday's post, is denying something that you learn in high school, not in third grade.

This, however, doesn't make his claim any more sensible.  Angular momentum, you may recall from physics class, is in the simplest case (like whirling a weight tied to a lightweight string in a circle above your head) the product of three quantities; the mass, the tangential velocity, and the radius.  And what the conservation law says is that in a closed system that quantity doesn't change.  (Remember the "closed system" part, because that'll become important in a moment.)

The most common example of the Law of Conservation of Angular Momentum is the way figure skaters' rotational rate increases when they bring their arms in.  By reducing their effective radius, the velocity has to increase in proportion to keep the aforementioned product constant.  Most kids have seen this in effect, too; whirl a weight on a string, and if you pull the string to decrease the radius of the circle, the weight spins faster.

[Image licensed under the Creative Commons Gyroskop, CC BY-SA 3.0]

This is where Mandlbaur starts leaping about making excited little squeaking noises, and telling us that this can't be true.  He goes through a "thought experiment" wherein he argues that angular momentum isn't conserved, because if you reduce the radius (pull on the string to decrease it to, say, one percent of its original length) the rotational velocity would have to increase by a ridiculous amount.  Because we never see that happen, the Law of Conservation of Angular Momentum must be wrong.

What this ignores is the "closed system" part I mentioned above.  Angular momentum is conserved if there is no external torque -- which there damn well would be if you have a mass moving that fast, produced by the air resistance.  Plus, there's the little issue of the centripetal force -- put simply, how hard you'd have to pull on the string.  Centripetal force is defined by the formula F = mass x velocity^2 / radius, so as you can see, as the velocity rises and the radius decreases, both contribute to it becoming progressively harder and harder to hang on to the string.  Since the way this force is transmitted into the weight is the tension in the string, eventually the string breaks, and the weight goes flying off in a direction tangent to the circle until it meets an opposing force, like the windshield of your neighbor's car.

A physicist named Val Rousseau did a much more thorough takedown of Mandlbaur's claims, and I won't steal his thunder by repeating all of his careful debunking.  Suffice it to say that Mandlbaur doesn't stop with trashing the Law of Conservation of Angular Momentum; he also says that Newton's Second Law, the Work-Energy Principle, both Laws of Relativity, and all of quantum mechanics are also wrong.

Oh, and light actually has mass.

What's interesting about Mandlbaur is how combative he is.  Anyone who criticizes his work is "childish" and is engaging in "character assassination" or a "blatant ad hominem."  Sorry, dude, saying "you are wrong" is not an ad hominem when you are, in fact, wrong.  To say the experimental evidence lined up behind all of the laws he's happy to jettison is "mountainous" is the understatement of the year.

And yet... he has fervent followers.  He's a "maverick," they say, a courageous knight taking on the dragons of the hidebound scientific establishment.

I've never understood the compulsion people have to follow someone simply because they're anti-establishment.  Surely, it matters more if they're right.  Right?  By itself, being anti-establishment doesn't make you a knight, it makes you Don Quixote, tilting at windmills because you've decided they're monsters.

And if what you're claiming could be refuted in a high school physics classroom, I'm afraid you don't have a lot of cause to brag about how fearless you're being.

In any case, I urge you to take a look at Rousseau's site.  I'm deliberately not linking Mandlbaur's webpage because I'd prefer not to give him any additional traffic; you can find it if you're so inclined.  And if any of you are getting ready to @ me about how "the scientists have been wrong before!", don't waste your time.  Sure, they have, no question about that.  They were wrong about continental drift -- until the plate tectonics model was proposed.  They were wrong about the luminiferous aether -- until Einstein came along.  They were wrong about what caused malaria, cholera, and typhoid -- until the Germ Theory of Disease.  They were wrong about how inheritance worked -- until Mendel wrote his book about statistical genetics, and eventually a whole group of scientists uncovered the roles of DNA and RNA.

Get my point?  Sure, the scientists have been wrong sometimes, but they fixed it by coming up with a better theory.  Science works as well as it does because it self-corrects.  If your model doesn't fit the facts, it's superseded by one that does.  On the other hand, if you want to claim the current model is wrong, you damn well better be able to show that what you're proposing to replace it fits the experimental data better than the one you're planning to trash.

So once again, we have a blowhard crank (okay, maybe that was an ad hominem... oh well) who thinks he knows better than all of the physicists from the last four hundred years.  I'm guessing if he finds out I wrote this, I'm going to get a stinger of a response, but I'm ready.

Just about every physicist from Newton on down has my back.


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