Tuesday, May 24, 2011
Sunday, May 22, 2011
Camping is, as incredible as his theories may sound, a charismatic leader, and he was able to convince hundreds if not thousands of people that his prediction was true and correct. We've seen this kind of behavior before, and not only in a religious context. What about those people who were swindled of their life savings by real estate scams? What about Enron? Here were normal, perhaps slightly gullible (who isn't once in a while?) people being taken advantage of by someone with more power. What did we do in those cases? Pursued the culprit, the mastermind, both judicially and financially. Why not do the same to Harold Camping?
Camping is worth over $70 million, none of which he gave away in these "last days." But his followers did: some quit their jobs, some sold their homes and some even metered out the last of their savings to last them through - you guessed it - yesterday. They've been had, pure and simple. And they should pursue legal and civil action against the man whose fault it is.
If you are going to be responsible for the lives of people who trust your message, you should remain responsible for those people after your message has failed to bring change. We hold financial and corporate scam artists accountable - we should hold religious scam artists accountable, too.
Friday, May 20, 2011
Everyone knows that there exist in nature "old women." These "grans," as they are technically referred to, live nearly forever, relentlessly refusing to give up the ghost, stretching their lifetimes out indefinitely. Carbon-14 is one of these, too. As nuclei go, it may be pretty famous, but it's famous because it's anomalous... it lives too long. And a new paper in Physical Review Letters finally explains why (publicly available version here).
To get to the crux of it, the issue is the approximations we always use in science to get "first order" solutions to otherwise almost impossibly difficult problems. Some equations are just so convoluted and complicated that they can't be solved analytically (ie, in an exact mathematical way), so they have to be approximated. This is typically done by taking the equation and breaking it down into small chunks, called a series, and determining how many of the "orders" of the series are necessary to get a reasonable answer. The first piece of the series is zeroeth order, then first order, then second order, third order, and so on. Generally, at a certain point, adding more orders to the series will result in smaller and smaller changes to the solution, so you can then reliably pick a cutoff and can solve the equation "to first order." A lot of good and interesting physics has come out of these bulk approximations - we can model a nucleus like one particle outside of a larger particle instead of as dozens of individual ones, for instance - but sometimes the approximation just isn't good enough. Carbon-14 is one of those cases.
The authors, including a friend of mine, have taken into account numerous things in order to get past the approximation and get to the basic principles of how a carbon-14 nucleus is formed and behaves. This includes building it up particle-by-particle and accounting for not just nucleon-nucleon forces, but also three-body forces as well, and sticking all of this information into the Schroedinger equation of quantum mechanics. By examining both carbon-14 and nitrogen-14, which 14C decays into, the authors could determine any systematic uncertainties in their approach.
Now, I mentioned that we use the approximations in order to make the math "doable," and that's still true. By starting from basic principles and not using approximations, the authors made their lives very difficult. But fortunately, they didn't have to solve these equations by hand - enter Jaguar, the ORNL supercomputer. It is only with this level of computing power that such a study becomes feasible.
In the end, the authors found that a sort of "cancellation" was occurring in certain components of the physics governing the nucleus of 14C, which was allowing for the anomalously long half life. But a lot of work went into discovering this. Sometimes the most interesting things exist just under our noses.
P. Maris, J. P. Vary, P. Navrátil, W. E. Ormand, H. Nam, & D. J. Dean (2011). Origin of the Anomalous Long Lifetime of 14C Physical Review Letters, 106 (20) : 10.1103/PhysRevLett.106.202502
Monday, May 16, 2011
Monday, May 9, 2011
I recently finished a book (found and purchased cheaply at a discount bookstore) written by a journalist about nuclear energy. In growing up in Albuquerque and meeting the people involved, she learned about the nuclear fuel cycle and so forth, and came to the conclusion (gasp!) that nuclear energy isn’t bad… in fact, it might just be good. I don’t wish to get into a technical critique of the book (she’s a journalist, after all, she won’t get some of the more scientific details… like that ORNL didn’t close, but K-25 did…), but I wanted to touch on a specific point.
At one point in the book, she quotes a study done by a University of Pittsburgh physicist (Bernard L. Cohen) and published in one of his books, The Nuclear Energy Option (the book is “available” here, but when I say available, I mean there’s only a cached copy of it). I haven’t been able to find the specific study yet (it’s difficult to read a book which only partially exists…), but the basic premise (as Cravens paraphrased it in her book) was this: the number of news stories about nuclear incidents is way out of proportion to the actual danger posed by nuclear incidents. To make his point, Dr. Cohen took a sampling of stories from the New York Times for an entire year, counting the number of stories on mundane things like car accidents, as well as the number of stories about nuclear. He then plots them against the actual number of deaths for the given danger in that year, and fits a curve to it. What he concludes is that, if the copiousness of news stories is to be used as a gauge for the number of deaths, we should anticipate something like 700,000 deaths due to nuclear related incidents per year. Yeah, right. (Cohen also found this to be absurd.)
Since I haven’t yet been able to locate his original study (I plan on ordering a copy of his book), I’ve decided to take my own sampling. In order to get a fair assessment across the board, I went to NPR, Fox News, The Huffington Post, and two small, local news channels (9News in Denver and KnoxNews here in Knoxville). I searched each news agency for three representative danger categories: "car accident," "tornado" and "nuclear." Because of the way each individual site performs its story search, the absolute numbers shouldn’t be given too much weight, but the obvious trend is still easy to see. Here’s what I found:
|# of stories by type of death (2010)|
|news agency||car accident||tornado||nuclear|
*Actual deaths: car accident statistics for 2008 from AAA; tornado statistics for 2010 from NOAA; nuclear statistics for 2010 from WHO/UN. Consider that even the Chernobyl accident, the worst nuclear accident on record, will likely result in only 4000 total deaths – TOTAL – which is still only a tenth of the number of people who die in car crashes every year.
To put this in a more visual form, here’s a bar chart:
And here’s a graph plotting the averages against one another:
Note that in BOTH plots, I’ve had to make the y-axis log scale (meaning each tick is a factor of ten) to fit everything in. In this last graph, in fact, I had to make the number of deaths in 2010 due to nuclear-related incidents (that would be a bit, fat ZERO) into 0.00001 simply so that Open Office would know to draw a point there.
The conclusions are obvious – the media is fear-mongering the public with regard to all things nuclear, and there’s little doubt that this feeds the public misperception of the dangers of radiation and nuclear plants. The dangers associated with nuclear energy and radiation are being grossly misrepresented – on a logarithmic scale, no less – and the public is falling for it.
As Chuang Tzu once said, "Great truths do not take hold of the hearts of the masses. And now, as all the world is in error, how shall I, though I know the true path, how shall I guide? If I know that I cannot succeed and yet try to force success, this would be but another source of error. Better then to desist and strive no more. But if I do not strive, who will?"