2008/04/06 Attiyah and His TheoriesI guess when you're an astronomer, you have to expect to be the target
of the occasional crackpot with their personal theory of the universe. My
antagonist is
Attiyah Zahdeh.
I don't know where he's from
(although devious research indicates he's on central time, so my current
theory is Chicago), or how he got my email, but for a couple of years now
I have been getting emails of which the following is the most recent example:
I have also been spammed with Attiyah's Sun Theory, which I think says that daylight is caused by charged particles (or X-rays, or whatever) hitting our atmosphere--much the same as the mechanism causing the northern and southern lights, and with Attiyah's Hologeomagnetosphere, which asserts that the northern and southern lights are generated by electrical currents in the earth's molten core turning our ionosphere into a giant CRT monitor. I once thought that these were created as jokes--that "Attiyah" was just the psuedonym of a humorist. Dozens of emails (and several years) later, I'm convinced that Attiyah is real and in earnest. In fact, I've discovered that he visits his theories upon astronomy message boards with some regularity, where he has revealed complete ignorance about how the scientific process works by demanding that others attempt to disprove his theories (the burden of evidence is on the newcoming theory) and by flatly ignoring the evidence that was provided against them. Two years ago, I myself was duped into providing a detailed refutation of Attiyah's Sun Theory, only to have my response disappear into the abyss of cyberspace. But I'm not bitter. In some ways, Attiyah's doing a lot for science
education by getting ameteur scientists to review how we know what we
know--reminding everyone that the reason we have such a widely adopted
set of theories is that they are testably confirmed and mutually consistent.
If only intelligent design, creationism, and young-earth hypotheses met
with half the ridicule that Attiyah's theories meet on the message boards.
Attiyah's only mistake, really, was failing to incorporate a little theology
into the mix.
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2008/02/17 Playing, and Why The Fast Track Wasn't the Best TrackA NY Times article on playing today got me thinking about the indirect path I took to being an astronomer. I went to school at Harvard with a lot of very bright people (and even managed to marry one of them). The undergraduate academic experience at Harvard was a little hard on me, though it took me several years after I graduated to fully understand why. The first reason is pretty common to undergraduates at Harvard--intelligent and accomplished people who are used to being the best at what they do are suddenly brought into contact with quite a few people who are better than they are. For driven students, this blow to the ego can undercut some of the self-assurance necessary to work productively. What was harder on me than turning in my "big fish" status as I moved to a larger pond was the cultural mismatch that existed between myself and the faculty with whom I came into contact. Harvard physics (or at least physics instruction) has a strongly theoretical bent to it, and while some modicum of application is maintained through the 2 lab courses we were required to take, I was always given the impression that applied fields were a cop-out for theoreticians who couldn't make the cut. The culture of disdain for experimentalists kept me on a theoretical track throughout college, long past the point at which I was "having fun". I can tell when I'm having fun, because I play. Playing, as defined in the article above, is "apparently purposeless activity." For me, that means trying to answer questions that aren't on the homework, just out of curiosity. It means starting projects, building things, and enjoying it. The farther I went down the theory track, I less I played with what I was learning. The undergraduate curriculum left little time for doing anything that wasn't strictly required, which was one problem, but the larger problem was that the path I was taking wasn't supporting the kind of playing I like to do. I got lucky when I enrolled in an introductory electronics class with Paul Horowitz. I found myself, outside of class, trying to teach the computer I'd build to shoot a dart at a mechanical dinosaur. I modified a remote sensing, squawking penguin to spit water at passers-by. I didn't realize it at the time, but I was playing. After I graduated, somewhat at a loss for what to do, and burnt out with physics, I asked Paul if he knew anyone I could work for. He introduced me to Dan Werthimer at Berkeley, where I started designing and building electronics for SETI. Out of school, I suddenly had a lot more time for diversions, and I began learning Python and using it to write evolving programs that mutate their own source code. I tried writing speech recognition (I'll post someday about language acquisition, one of my favorite diversions). I made a guitar website to learn cgi programming. Most telling, I (mostly) gave up video games for computer programming, which indicates the degree to which this really was playing for me. Eventually I stumbled into radio astronomy, where the physics that I learned
(and really did love), met with the electronics and programming that I loved
playing with. An incredible number of skills that I currently use were
developed during my diversions, including Python programming, soldering, web
programming, and signal processing. I never took classes in any of these
things, I just learned them from my projects. What I didn't understand as an
undergraduate was that working can really be "playing" if you find the right
job, and that if you don't play with what you're doing, you might be barking
up the wrong tree. Moreover, I was able to learn and accomplish much more
when I was in a laboratory environment, playing with what I was learning,
than in a classroom listening to lectures. Of course, you can't learn
everything from playing--you need people to take you beyond what you have
immediately at hand--but for me at least, I would rather this be the exception
to the rule. Playing shouldn't just be for kids.
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2008/01/19 Rain WaterI consider myself an environmentalist. I try to do the basic things around the house that help reduce my carbon footprint (you can calculate yours here) like installing compact florescent lights, installing power strips to prevent appliances like TVs from pulling current while "off", driving the minimum possible, eating vegetarian, and drinking soy milk instead of the dairy variety (cows are surprisingly bad for the environment). And I'm always on the look-out for something crazy and interesting to try for the environment. An idea I've been tossing around in my head (especially now that I live in rainy Puerto Rico) is harvesting power from rainwater. Part of my recent interest in rainwater, I must admit, has to do with the fact that we average about one water-outage per month here; I want backup water. However, my original interest, a year or two ago, was actually in generating electricity from the rain falling on my roof. Here are some order-of-magnitude calculations for what I might expect to get from this. Quick research indicated that average annual rainfall here is 62 inches (about 150 cm). This means that each square meter of rooftop collects about: 150 (cm) x 100 (cm) x 100 (cm) x 1 (g/cm^3) / 1000 (g/kg) = 1500 kg of water per year. If a story of a building is 5 m high, then the potential energy in that water is: Force x Distance = Mass x Gravity x Distance = 1500 (kg) x 10 (m/s^2) x 5 (m) = 75,000 (J) = .02 (kWhr) So PR generates .02 (kWhr/m^2/story) annually. My apartment building is about 10 (m) x 20 (m), and is 4 stories high, bring the energy of rainfall to 16 kWhr annually. If electricity costs $0.10 per kWhr, I could save a whopping $1.60 off my power bill annually. That probably won't ever offset what it would take to build the generator. Sigh. Of course, dams do exactly the above, but with an enormous collecting area
(not just a rooftop--an entire drainage basin). It looks like rain on
my roof isn't going to power my computer, though. But I still might try
to use the water to flush my toilet when the water goes off next weekend.
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2008/01/09 Hidden VariablesI've been having a few conversations about hidden variables lately, so I thought I would post about it. First a little background: Quantum mechanics (QM), as we know it, is weird. It is a classic example of science as a selection process, as I talked about in the previous post. It set about to solve the problem of predicting the locations, energies, and other microscopic attributes of fundamental particles. When the dust settled, we had one of the most accurate theories ever made (it predicts the mass of the electron to 14 decimal places), but the model used to make these predictions countermanded a lot of things we'd thought were true but never actually got around to testing--intuitive things like "a particle can only be one place at a time", well-established things like "no particle may carry information faster than the speed of light" (which is true, but can be violated over short distances), and most importantly for this post "if you had enough information, you could determine the outcome of any experiment." Nature's rejection of this last idea comes dangerously close to undermining the pillar of scientific philosophy that the universe is predictable insofar as it can be modeled and tested, and it offended a lot of scientists (including Einstein). What QM says is that there are certain pieces of information that are not simultaneously knowable. If you know a particle's position perfectly accurately, then it is impossible to know its momentum. If you know a particle's orientation along one axis, you can't know it along any other axis. For a long time, many people (including Einstein) thought that this was a shortcoming of QM--that these particles have "actual, hidden values" that QM just didn't know how to predict, and eventually there would be a better theory that could tell us what these values are. Those hopes were shattered in 1964 when John S. Bell proved that there can exist no hidden variables in a way that is compatible with QM. His predictions have been validated by experiment, showing that the reason we don't know the state of a particle is because the universe hasn't made up its mind (excuse the anthropomorphification) until you measure the particle. Crazy. I like to think of QM like a black curtain at a magic show that allows the universe (the magician) to perform all sorts of sleight-of-hand shielded from the eyes of the audience. On our side of the curtain, there are rules you have to follow--conservation of energy, speed of light, definity of location and state, etc. On the other side of the curtain, anything can happen, so long as when you pull it back out (when we make a measurement), the rules have been obeyed. The "curtain" idea isn't so far-fetched; it's an analogy to Feynman's well-tested theory that the outcome of an interaction is the sum over all possible interaction pathways. The universe takes advantage of this curtain to do things that we think should be impossible, like transmitting information about a measurement instantaneously between two particles that share a quantum state. Furthermore, the universe relies on the fact that we can never see behind the curtain (this is an interpretation of Bell's theorem) because if we could, we could use that machinery to transmit our own information faster than the speed of light, and that violates causality. Causality, by the way, is another principle that we cling to because it seems self-evident, but may in fact be wrong. It will take a unification of the theories of QM and general relativity to sort that out. Shifting gears into philosophy, I was talking with my uncle, who
came to visit last week, about how people look for meaning in their lives.
His argument was that back in human history, when the universe seemed a jumble
of arbitrary events, a physical, all-powerful deity with direct control over
all that happened was a powerful metaphor for finding meaning in the events of
ones life. However, as scientific knowledge has gradually encroached on
the idea that a god can take direct physical action in the universe, religion
has had to respond to the sense that science is pushing away meaning in life.
My uncle's thoughts were that a physical deity is becoming an outdated way
of looking for meaning in life, and that we need to think about
a more spiritual, humanistic God. I agree with this philosophy, but I
wonder if the rejection of the hidden variable hypothesis (the magician's
curtain) provides a home for religions that require a physical deity.
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2007/12/18 Philosophy of Science (a Rant)I read an article today that got my back up a little. Let me give a little background to explain why. I grew up in the rural, conservatively religious town of Rangely, CO. The first real experience I remember having that set me apart from the majority of the town came in 7th grade science class when we where discussing (you guessed it) evolution. Presented with another in the series of assertions that seems to constitute science education, I blithely bought in. My peers, who had been privately informed that evolution was not to be "believed in", discovered by waywardness, they dubbed me Monkey Boy. Yes, I know. Hilarious. This was certainly not the last time that I butted heads with conservatives in my town, and it stands at the base of a growing sense of disconcert that I have felt towards organized religion. In the meantime, I went on to study physics in college, and am now a graduate student in astronomy (I do experimental cosmology). It has been surprising to me, now that I have started being introduced as an astronomer, to suddenly to have became an "Interpreter of the Voice of Science" (preacher) for people who want to know how our universe came to be. The reason the above article got my back up was that I've always been careful, in these situations where I find myself describing the history (as we know it) of the universe, to stress the differences between science and religion. It's confusing terrain because cosmology has only recently come into the realm of science. My "what is science" speech usually ends up something like the following: science isn't a body of knowledge (despite what constitutes science education), or a belief system, or a religion. It is a methodology. Its groundings are philosophical, but that doesn't make its results philosophical. Science started from the philosophy that the universe is predictable: that one can predict the outcome of an experiment if one knows the initial conditions to sufficient accuracy. Out of this philosophy (which the microscopic, quantum universe has helped us to understand is not strictly correct), a method was devised for arriving at an understanding of the predictability of the universe. Hypothesize, Predict, Experiment, Analyze, Conclude. Elementary school science fair stuff (except that "conclude" now means "peer review"), but still confusing. Science is a level playing field where anyone can make up any theory they want, in the face of all current knowledge if they want, using any strange force or being or Flying Spaghetti Monster, and science has nothing to say about it until you make predictions, devise an experiment to test them, and peer review to make sure it's reproducible. Science works like infants learning shapes--pick a block, try to jam it through the hole, and repeat until you succeed. The framework that seems to work best for predicting the outcomes of experiments involves math. I'll save a discussion of why this might be for another blog, but it's important to realize that it didn't have to be this way. The universe could have chosen to play by different rules, or perhaps there are even models that can predict the outcomes of all the various experiments we've tried without using math. Math is just a model we have that works. Once you have two models that have equivalent predictive power, science has nothing to say again. Yes, I know about "Occam's Razor", but that's philosophy again, despite its popular portrayal as a pillar of science. I get frustrated when people (even scientists and cosmologists) misunderstand science to be a body of knowledge, or a set of "transcendental laws", because (it seems to me) it's putting the cart before the horse. Whatever laws and rules we have are only as good as the degree of testing they have undergone, and are subject to revision and replacement as new experiments reveal their flaws. And we know they're flawed. The two most accurate physical models we have--gravity and quantum mechanics--are mutually inconsistent, and neither of them are able to account for an accelerating expansion of the universe (the "Dark Energy" problem) or for motions on galactic scales (the "Dark Matter" problem). So how can a self-respecting scientist hold up a "transcendental law" and claim it is more than our current best model? My personal opinion is that referring to science as a body of knowledge
makes it akin to religion--something transcendental and immutable (and
inaccurate) handed down from above. What makes science science are
the error bars:
little reminders that our models are only as good as the extent to which
they have been tested.
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