Archive for April, 2013

It’s called the Higgs boson. Get used to it.

Tuesday, April 30th, 2013

Apparently some physicists are arguing that the Higgs boson shouldn’t be called the Higgs boson:

“I have always thought that the name was not a proper one,” said professor Carl Hagen, in an interview with BBC News.

“To single out one individual marginalizes the contribution of others involved in the work. Although I did not start this campaign to change the name, I welcome it.”

According to the BBC, key contributions to Higgs theory have been made by Francois Englert, Peter Higgs, Gerald Guralnik, Tom Kibble, Robert Brout and Carl Hagen, five of whom spoke at a press conference last summer to announce the discovery of what was thought to be the Higgs boson.

Only professor Higgs received a huge round of applause from the audience.

 

It’s true, I gather, that a bunch of people came up with the theoretical ideas leading to the prediction of the Higgs boson, so I suppose it is unfair that Higgs gets the particle named after him, but there’s really not much to be done about it. It’s been called the Higgs for an awfully long time, and I don’t see any way it’s going to change.

This reminds me of Stigler’s Law of Eponymy:

In its simplest and strongest form it says: “No scientific discovery is named after its original discoverer.” Stigler named the sociologist Robert K. Merton as the discoverer of “Stigler’s law”, consciously making “Stigler’s law” exemplify itself.

The Higgs boson actually isn’t a great example of Stigler’s Law, because nobody disputes that Higgs is one of the people behind the particle. A better example is Gresham’s Law in economics, which turns out to have been stated by none other than Copernicus 40 years before Gresham got to it.

There are a bunch of other examples. To cite just a couple,

Just look at Leonhard Euler and Carl Friedrich Gauss, indisputably two of the most important mathematicians of the 18th and early 19th centuries. And yet Euler’s number (better known as the constant e) was actually discovered by Jacob Bernouli, Euler’s formula was more or less demonstrated by Roger Cotes three decades before Euler, Gauss’s Theorem was discovered by Joseph Louis Lagrange and first proved by Mikhail Vasilievich Ostrogradsky, and Gaussian distribution was introduced by Abraham de Moivre 61 years before Gauss popularized it. Euler and Gauss were unarguably great mathematicians, but going by everything named after them you’d think they were the only mathematicians from 1700 to 1850.

To tell the truth, I have an ulterior motive for posting this. On several past occasions I’ve tried to remember the name of Stigler’s Law and been unable to come up with it. Now I’ll always have a place I can go look it up.

Meeting at Ohio State

Tuesday, April 23rd, 2013

I just got back from a great workshop at Ohio State University, organized by my collaborator Paul Sutter, on Innovative Techniques in 21-centimeter Analysis. This was a very small (~25 people), tightly-focused meeting. I like these a lot more than the gigantic meetings I sometimes go to. The topic was an area in which I haven’t done any real work yet, but I hope to soon, so it was extremely helpful to get up to speed on the state of the art.

The meeting was about measuring the 21-centimeter radio waves from hydrogen at very high redshifts, in order to map out the distribution of matter at times much earlier than the present (but much later than the cosmic microwave background radiation, which is the main thing I study). Cold hydrogen atoms like to emit and absorb radiation at the specific wavelength of 21 centimeters. This radiation, like all radiation, is shifted to longer wavelengths by the expansion of the universe. This redshift is greater at greater distances, so by observing this radiation at different wavelengths, you can map out the distribution of stuff in the universe in three dimensions.

At least, that’s the idea. The measurements are incredibly hard, because the signal is incredibly faint: it’s 1000 or more times fainter than other, more local sources of radio waves, so separating the signal you want to see from all the other stuff is a big challenge.

One of the speakers was Jeff Zheng, University of Richmond class of 2011, who did some great work in my research group when he was an undergraduate. He’s now a second-year graduate student at MIT. Here’s what he talked about:

The Omniscope: developing scalable technology for precision cosmology

Jeff Zheng

I describe the design and current status of the Omniscope, a 21 cm interferometer architecture optimized for scalability to very large (10^4-10^6) numbers of antennas N. By exploiting a hierarchical antenna grid layout, the correlator cost scales as N log N rather than N^2, and massive baseline redundancy enables automatic calibration and identification of bad data and failed components.

I’m pretty sure he was the most inexperienced speaker there, but you’d never know it from his talk, which was excellent. It’s great to see one of our graduates out there doing such top-notch work.

Matt Yglesias, Bayesian

Monday, April 22nd, 2013

Matt Yglesias uses the Reinhart-Rogoff economics fiasco as a springboard to talk about When to Take Empirical Evidence Seriously:

So when you look at a purported empirical finding you need to ask not only how strong is the evidence, but what’s a reasonable prior assessment before looking at the new empirical data. A correlation is never sufficient to establish a causal relationship, but it might be good evidence for the existence of one or else it might not. That depends, in part, on how strong your theory is.

Basically, he’s advocating the position, often attributed to Sir Arthur Eddington, that you should never believe an experiment until it’s been confirmed by a theory. That position is usually thought of as at least partly a joke, but, as I’ve mentioned before, it’s really just an expression of sound Bayesian reasoning. New evidence causes you to update your prior beliefs. Your new level of belief in any given proposition is determined by both your prior belief and the evidence. It’s not just OK to take your prior beliefs into account; it’s mandatory.

I’m glad to see that Yglesias understands this. He attributes his understanding in part to Nate Silver’s book, so I guess Silver is also sound on this subject. (I haven’t read Silver’s book, so I can’t confirm this, but it doesn’t surprise me.)