Where to start? Why not with something obvious: the blog title. Shaken, not stirred! Where does this even come from? For one, my (now obvious, *sigh*) affection for James Bond movies. But of course there is also a relation to science, or more specifically: my project. So what is this project all about?
My "victim" right now is something called "volcanic tremor". In essence, this tremor is like an earthquake on a volcano, but unlike an earthquake, it doesn't last for a few seconds but for minutes or hours or sometimes weeks! Crazy shit, eh? But what's even more interesting, a lot of the times this tremor happens the volcano is doing something, like, uhm, ... erupting! Kind of like, say, when your TV gets these little hick-ups where you see black and white stripes gliding across the screen (I know, how old-school does it get?? To be fair, for this analogy to work we have to think back to the times before plasma TVs. Anybody remember those days? But I'm diverting...). So when your TV does that once in a while, you hit it on the top and usually that solves the problem. But when it doesn't wanna stop the whole stripe-thing you know for sure it's up to no good! And you better watch out that it doesn't blow up in your face... just like the volcano! So that of course explains why some of us (granted, definitely the more nerdy part of the population) are really interested in this tremor thing: Where does it happen, what does it look like when it happens, and WHY IS IT HAPPENING AT ALL??? OK, this last question we could ask ourselves about many things, but let's save this discussion for another day.
So first things first: Where? There's many answers to that question, but for now I went with a pretty horrible location... Hawai`i! Roughing it for science, as always. But hey, we all have to make sacrifices! So I went there a few months ago, and with the help of my awesome friends at the Hawai`an Volcano Observatory got some examples for tremor that they recorded. Now what?
This gets us to the second question: What? OK, for one we can just look at the tremor records. They look like this:
Mostly a bunch of wiggles, sometimes with a few spikes. If you're a really really optimistic person you could say it looks somewhat pretty, maybe artistic (the discussion about the definition of art will also be left for another time...), but that's definitely a stretch. The only thing that we can say for sure is that it's more wiggly in the end, compared to the beginning. So now what?
This is where all the fancy stuff comes in (and where I wish I had first of all actually gone to any maths classes in my undergrad, and second of all, if I had gone, paid attention to what my professor was trying to explain. Oh well.). The fancy stuff in this case is called "Fourier Transform". "Fou.... what????", I can hear you asking. "She must be crazy", I can imagine you thinking (Darn, I think you're right. As you know, sanity isn't exactly my strong suit... but hey, it wouldn't be half the fun if I was actually sane, don't you think? Yikes, I'm diverting again, back to those crazy transforms.). It's not that hard, really. Imagine somebody has painted a picture, and now you're looking at it. You know all the different colors, because they're still lying around on the floor (Yes, the painter isn't exactly the tidiest person in the universe, and no, of course this is not based on my personal experience at all, and also, again, what about the fun??). So anyways, the colors are still there, but the painter mixed them to get different shades and tones. But since we know the components we can roughly figure out how much of each color was used to create a particular shade on the canvas. Makes sense? So I basically try to figure out which components are needed to make tremor. And once we know that we can try to work out where the components are made. It's like, yeah, we had this much yellow and this much blue to make some green, but where does yellow come from? And then we go to the paint factory and ask the guys who work there, hey, where does the yellow come from? I really like it, it's so bright and shiny and happy... Unfortunately there is no factory for volcano parts, so I can't just go and ask. This then gets me back to the point where I remember all those math classes in undergrad that I spent sleeping, eating ice cream in the sun, drinking beers, ... and the circle is closed.
So anyways, to get back to the point, in super short, there's this wiggly thing, some sort of shaking that happens when volcanoes blow up, and all I have to do is try to figure out where the bright shiny happy parts that make the wiggles come from. Pretty simple, eh?