Theory vs. Observation

In astronomy there are theorists and observers. Theorists do scary things like path integrals and observers do tedious things like data reduction, and somehow the field has managed to inch forward over the centuries to advance our knowledge of the universe. At one point astronomers were often both, but these days that is rare.

This year, Cosmology on the Beach was populated by many non-astronomers and certainly many theorists, so that might be why the question, "You said ellipticals don't have disks; does that mean they don't have star formation?" was not too out of place. The theorist lecturer answered, basically, yes, and then went on to muse on why there is this difference between spirals and elliptical galaxies. It occurred to me that an observational astronomer might have went into some detail about what different galaxy surveys have found, examples of observed star formation in ellipticals, and the properties of both. By glossing over details and giving the simple answer (yes), the theorist's answer was perhaps less true than my hypothetical observer's answer. The real world is more complicated. But instead of detailed examples and caveats, the theorist's attempt to answer "why" was perhaps more meaningful.

Thus I am writing this instead of listening to discussion which has now moved on to the subject of inflation theories (both less true and less meaningful). I wonder if the statement: "Observers are concerned with what is true; theorists are concerned with what is meaningful" is either true or meaningful. Observers (and experimentalists) collect facts about the universe. Theorists try to put these facts together into a coherent whole and derive new facts. Obviously both would argue that they care about both what is true and what is meaningful, and they would be correct, but not in a meaningful way. ;-)

Most theories end up being falsified by observations, so I think it is easy to accept the first half; but what about meaning? Can meaning even exist without truth? I would say yes, but it is not obvious. I think meaning is really found in connections, processes, and dependencies, whereas facts are static. Facts are independent of other facts. Regular readers may not be surprised that I prefer change over stability and processes over products, and perhaps that is why I'm not an observer.

I think it's not much of a stretch to say that truth is stable, final, while meaning connects truths to each other and to people. Observations themselves lack meaning unless they say something about theories... so for example, observations of N stars and their positions, brightnesses, colors, etc. don't say anything meaningful about the universe until they are connected with a theory of star formation. On the other hand, observers collect beautiful truths that stand on their own while theorists only ever make models and attempt to describe reality with math. Observers touch reality itself, while theorists play around with representations of reality. Perhaps that's why I'm not a theorist either....

How much of this "theory vs. observation" divide is a result of personality differences, and how much is a result of the need to specialize? Theorists and Observers are both important and needed, and although both admit that the other has their uses, both have put themselves into a box of one or the other. Both make jokes at the others' expense: theorists aren't connected to the real world and observers fit lines through scatter plots. Sometimes I laugh at these and sometimes I find myself bothered by them. Can't we all just get along? Of course, whenever a joke is directed at me I can say "no, not an observer!" or "not a theorist!" And then I say "phenomenologist" and vanish in a puff of smoke.

But then I find myself in a puff of smoke! And I'm not even sure I can use the word "phenomenologist" legitimately. I simulate things and analyze the simulations, so I don't do scary integrals and I don't do tedious data reduction. I'm probably close enough to a theorist to be grouped with them, since basically my computer calculates the integrals for me. It turns out a lot of science can happen from inside puffs of smoke.

Death

I decided to pull out some Tarot cards today, and the first card was Death.

Don't worry, it's just a metaphor. And a pretty accurate one too. A lot of things are changing right now and a period of my life is ending. I'm in the middle of figuring out what the next stage of my life is going to be like. And before anything new can happen, the old has to become old. It has to die. Only with death can there be birth; only with birth can there be death.

Death is not an evil thing, nor always bad, but it is often scary, and sometimes painful. We become comfortable in the life we have and start to fear that it won't always be so comfortable, that at some point something will be different. Fear of death is fear of change, for death is the first step to change. I mostly mean metaphorical death here, as in ending, leaving, or being destroyed, but physical death too. Physical death is the ultimate change from which there is no changing back (in so far as anything can really be changed back). But we forget we have already gone through such a transition: birth. We come into this world and we go out, there is no escaping this truth, for the nature of life is change. Creation and destruction are the two sides of that change and merely different ways of describing a single event.

I was at a funeral recently and as I listened to the pastor, I became convinced that the nature of religion is to address in some way the fear of death. And in my opinion, most do this the completely wrong way, which is to get rid of death entirely. When you die you go to heaven. Death is not real, you won't really die, the people you love won't die, everything will be perfect in the light of God. "Others have to say 'goodbye', we get to say, 'see you later'." To me that means no growth can occur, no moving forward but always looking back - eternal stagnation and sameness - the absence of change and so the absence of life. The absence of life indeed - the very thing that was feared - but also the absence of death. What is left? No, I would rather say goodbye. I would rather be able to feel loss and sadness and pain. How can one grieve if there is nothing to grieve? How can I rejoice in the new if I never let go of the old?

I don't mean to be too hard on the idea of heaven, though. I don't mind if people believe in what gives them comfort, and I don't mind interpreting heaven as a metaphor even though people take it literally. ;-) But I will continue to say goodbye. And hello! (FYI that means to babies, in this analogy.)

One of my favorite movies is The Fountain and its major theme happens to be death. As the husband struggles to cure his dying wife, he spends less time with her. By trying to have her forever, he loses her now. And the wife instead becomes fascinated with the story of the Mayan creator god, who plants the tree of life from his own dying body: "Death as an act of creation." "Death is the road to awe." (One could say, the road to "awesome!" But one wouldn't.) And in the picture on the Tarot card, the dead one is placed in the fetal position in the womb of the earth. The snake sheds its skin to permit new growth. Or, to put it a little grossly, phallic and wombic imagery come together to create new life. (They make baby imagery.)

Having said all that, I'm not looking forward to my own metaphorical death at all! But I have to remind myself that Fear won't help anything... and then I have to eat some chocolate and calm down.

P.S. Almost forgot to mention another thing about The Fountain. I remember thinking the credits looked a bit like cosmological structure formation, but I didn't take it quite this far. Pretty awesome.