Monday, May 09, 2011

A Thought From Feynman

I'm doing a bit of research and I came across an interesting piece. It's an adaptation from Richard Feynman's commencement speech at Caltech in 1974 in which he discusses what he calls "Cargo Cult Science". In other words, things that sound scientific, but aren't.

In one portion, something stuck out at me:
Millikan measured the charge on an electron by an experiment with falling oil drops, and got an answer which we now know not to be quite right. It's a little bit off, because he had the incorrect value for the viscosity of air. It's interesting to look at the history of measurements of the charge of the electron, after Millikan. If you plot them as a function of time, you find that one is a little bigger than Millikan's, and the next one's a little bit bigger than that, and the next one's a little bit bigger than that, until finally they settle down to a number which is higher.
This is an important lesson to remember. When something new is discovered in science, there's often a great deal of uncertainty to it. But after thorough investigation, it generally settles down on an answer, even if that answer is quite different than the initial estimate.

Yet the gasbag Ray Comfort seems to think that's a problem. He's repeatedly complained that the Big Bang can't be true because astronomers have been furiously revising the estimates and made some pretty significant changes as we've beaten down the errors and refined techniques. He proposes that things that are eternal and unchanging are inherently better because you can't trust that darned Big Bang since the estimates keep changing.

Similarly, I guess Ray can't acknowledge the charge of an electron. Even though it's a fundamental quantity that underlies so much of electronics and physics and if it were wrong, they would crumble, if the estimate changes, it can't be trusted to exist in the first place.

This kind of thinking isn't just wrong. It's abhorrently stupid. There's no good response for such abject lunacy. The best we can do is point out the flaw and mock it, dissuading others from thinking it's a tenable position.

1 comment:

Stephen Uitti said...

The idea that measuring the expansion rate of the Universe is really quite difficult also never occured to Ray Comfort, and others. These are people who've never done anything that's difficult. But as near as i can tell, the age of the Universe appears to be known to better than three significant digits. That's much better than just a few years ago when it was known to within a factor of two. A better framing is not that the value is changing so much as the error bar is shrinking. And, presenting a range: 8 GY to 14 GY, is easier to follow than a number with an error bar: 13 +/- 3 GY. Or these days, 13.75 ± 0.11 vs 13.64 to 13.86 GY. I'm comfortable saying "thirteen and three quarters billion years" in public these days.

A decade or so ago, i saw a really funny article showing a plot of the diameter of Pluto. The values kept going down as telescope resolution improved, and the lower limit got smaller. The article suggested that Pluto's diameter would go to zero in 2010, and thereafter, it would become imaginary. We now know that Pluto ceased to be a planet in 2006. It's interesting to note that the diameter estimate for Eris has been shrinking too. I'm not totally convinced it's bigger than Pluto.