Tuesday, May 4, 2010

Some Science Fiction and Fact, also, What I Do at Green Bank

So, you might know by now that Science! is not about a bunch of men in white coats, hanging out in dark laboratories and shouting "Eureka!"  You know that women are involved too, after all, and even more should be than are, especially in this country.

But, female or male, unless you are extraordinarily brilliant or lucky or both, science is nothing so glamorous.  Still worth doing, in my opinion, and even better, still interesting enough to write about.  But our idea of the The Scientist, as well as how science works, is often quite off base from reality.

So over the next few days, I'm going to talk about some science myths.  If you know any, or have any insight, comment or email, and we'll talk about them.

Here's you're myths for today.

Science Myth 1:  Scientists figure monumental things out after working hard.

Science Fact:  Actually, that could be true.  But that happens maybe once or twice in your career, and rarely by yourself.  Do scientists really have an idea of how things will happen, do an experiment, and shout excitedly when what they expected happens?

Once again, maybe, but probably not.  More often, you stare and stare and run trial after trail and get results that Make No Darn Sense, and if the funding runs out before you get any further than that then you write the It Made No Darn Sense paper, because the staple of scientists is How Many Papers Can You Write?, not, unfortunately, What All Did You Figure Out?

Discoveries happen, of course, and the ease of the hypothesis->experiment->result model varies by discipline:  it might work well still for medical fields, sociology, and others, but is pretty much impossible anymore for physics.  Discoveries do happen--but it is often over years, decades even--and they happen by small steps, not great leaps.  Mostly anymore, they happen through collaboration, and not the sheer genius of one individual.

Science Myth 2: Scientists work individually.

Science Fact:  Scientists collaborate.  In the time of Einstein and thought experiments and Tesla locking himself away in his electricity lab, the kinds of things that could be discovered were sitting at the surface, where a brilliant individual might get at them through his or her own work alone.

Not anymore.  Science is highly specialized, these days, so that one person cannot possible know everything even within her sub-field of the sub-set of science that is her chosen field.   So you need your expert in, say, nuclear physics, combined with your expert in astronomy, combined with your expert in condensed matter, to go about condensed matter nuclear physics in space, because the general areas have been discovered pretty much to everyone's satisfaction.  It's the in-betweens and nuances where the new information still awaits to be found and interpreted.  And it's really, actually, more specialized than that, I just don't know much about condensed matter nor about nuclear physics, nor if they would even go together in space--perhaps in a neutron star-- to give you the real categorizations.  With the way data acquisition and analysis works, you often need your computer guy, your electronics gal, your theory head, AND your condensed matter specialist. 

Furthermore, you have people like me.  Graduate students--and in my case technicians--that do the Monotonous Stuff, to free the PI (principal investigator, certainly not a private one) to do the assimilating and thinking.  Or mostly it's that the amount of computer data sorting, manipulating, and arranging so that you can get an idea what you're looking it involves so many person-hours that one person could not both put in those hours and write his paper and teach his science classes in any sort of timely fashion.  And it is sad but true that churning out the papers is the mark of a productive, and thus tenure-grant-able and generally fund-able scientist.  Just like anybody else, scientists need income to practice science.

Science Myth 3: All science is relevant.

Science Fact:  This is my opinion, and it does not lessen my love of science--but I do not find all of it very relevant, important, or interesting.  This isn't a Physics verses Everything Else rant, I'm saying that sometimes when you are doing science, the Big Picture of all those details you are pouring over is really actually not very spectacular.

Case in point:  my research with the Green Bank telescope.  We are looking for what is called the "fine structure lines" of ionized (meaning, missing its electron) hydrogen.  If you read my article on quantum mechanics, it probably won't help you at all with "fine-structure", which is nonetheless an entirely quantum mechanical phenomenon.

In high school chemistry you learn about transition lines in atoms, whereby electrons go from having one amount, or level, of energy, that the electron just intrinsically possesses, to another intrinsically pre-determined amount, by absorbing a passing light particle of energy equal to exactly the difference between the two amounts.  That, or else an electron already in a higher energy level spontaneously falls to a level of less energy, emitting a light particle instead.  By the frequency of the light, we can tell the difference in energy levels, levels that are intrinsically characteristic of the element, ion or molecule in question, and which computers (because no human can do this math by hand) armed with Quantum Mechanics have spent a great deal of time solving for many molecules exactly.

Well, almost exactly.  It turns out that Quantum Mechanics--the math that calculates all those energy levels--is, like everything else in physics, only an approximation.   If you take into account some other Staples of Physics, such as relativity (which I'm not going to attempt to explain) it turns out you have to tweak the math slightly.  The results of that tweaked math:  instead of having, say, two energy levels, with x joules between them, you have four instead, with y joules between them, and y is much much smaller than x.  It's called "fine" structure because the additional energy levels are spaced very close together, so that you can't really see them unless you are looking for fine detail.

But Quantum Mechanics + Relativity says they are there, and they have in fact already been observed. So as cool and relevant as that would be, The Combination of Quantum Mechanics and Relativity is not what is being verified or not, in my particular astronomy project.  We know that model does in fact work, and the fine structure lines I am looking for have in fact been observed.

Y, the difference between the extra energy levels, is so small, that they are darn hard to see.  In space?  Forget it.  Space is actually pretty noisy, especially in the radio frequencies where these lines are found, and the noise from electronic instrumentation (what you need your electronics gal for, which is so not me) is a constant problem.  Yet we are trying to see them in space anyway, in part because it would be cool, because it would round out the body of knowledge on the fine-structure quite nicely.

But it gets more complicated, because the environment in which we are looking determines whether these lines can be seen or not.  If conditions are one way, we think we will see the transition in absorption, whereby, remember, the atoms go to a higher energy level because they absorb a passing photon.  If conditions are another way, we think we will see emission instead, whereby an atom in a higher level goes to a lower and emits a photon.   If conditions are a mix, then we will see a mix, and that doesn't help us because absorptions and emission will cancel our ability to see either one out.  The conditions have to do with interstellar dust, which tends to scatter passing photons randomly, among other complicated and surprisingly boring things.  So if the our regions of ionized hydrogen, having a certain Quantum Mechanics + Relativity predicted set of energy levels, also have a lot of dust, one thing will happen, and if they don't have enough dust, something else will.  Or, maybe it's something else about the environment we have yet to figure out.

So what we are really looking at, when it comes down to it, is, do the three  regions of ionized hydrogen that we chose to look at, among all the many thousands of such regions visible to us, have dust in them, or not, and can we even say for sure that dust in the thing anyway?  That's it, that's the Big Picture of my project.

Is that relevant?

It could be useful to another astronomer, who might use the dust-or-not information to make some other observation that turns out to be immensely relevant to a model of physics that in turn is relevant to building technology here on earth.  And even if not, I am still quite for the whole Science for Science Sake, because Knowing is so wondering, and all that.

It just doesn't make for the easiest conversation at parties, trying to tell people what I do.  Even among other scientists--grounded in their specialized field and not familiar with mine--the reaction, just like my reaction to a lot of their work with blah blah blah nebulae and blah blah blah crystal shape of boron-doped silicon (actually, that interests me, because it's in solar panels) is a sort of "Oh, well, that's interesting."

Some science does, of course.  Make for good party talk, I mean.  Make for good technology, and high relevance to the world's problems.  But even when I was working on a "fuel cell" project, what we did was in essence tell a computer to do that Quantum Mechanics Math on every step of a multi-step chemical reaction, catalog that data, (which was calculated at absolute zero for simplicity, thus, not particularly realistic) and report it to the Principle Investigator, who nodded and filed that information away for the paper she will eventually write.  My name will be on it, but I can't really give you a good idea of how useful that information is going to be.

I don't say this to disdain science.  I just say it to highlight how specialized and large is our knowledge, and how progress now comes from each of the thousands of scientists that there are, hacking away at really tiny chuncks.  There's a lot of Darn Hard Work involved, and not so much "Eureka!"

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