(1) I know what martingale variables are, but I don't see why the non-martingale nature of the macroeconomic variables is relevant. Clearly, if you have figured out a novel way to predict the coming of the aliens ahead of others (or even just to predict its timing and other details more accurately), you can get rich by figuring out how their coming will affect the markets. This is perfectly analogous to a theory that will predict various macroeconomic variables more accurately than the state of the art, since these variables have predictable effect on asset prices. (In fact, once you have this information, they are no longer martingales for you, since e.g. if you know a recession is coming withing a year, the expected trend for countercyclical assets is upward.)
Or to put it differently, from all that you have written thus far, I still don't see a concrete example (either actual or hypothetical) of the thing whose existence you assume: macroeconomic predictions that are interesting, novel, accurate, and at the same time useless for beating the markets.
(2) I understand that there are hypothetical questions about monetary systems where an accurate answer would have no practical implications by itself. However, presently we are in a situation where there are deep and bitter disagreements even about the predicted consequences of the ordinary and standard monetary policy options. What I find implausible is that one could obtain correct answers of the former sort without a theory that would at the same time be able to give more accurate answers to questions of the latter sort (which would again translate into investment information in a straightforward way). It would be as if you had a theory of mechanics capable of predicting the motions of hypothetical planetary systems but of no use for practical technical problems.
(3) Regarding your point about theoretical vs. applied research in other areas, the same heuristic actually is widely applicable. Whenever you see people doing research into something that should have straightforward practical applications, but you don't see them running to monetize the results, something fishy is likely going on.
Of course, sometimes there is real insight that can't be monetized in any obvious way, like for example fundamental theoretical physics. However, there is an essential difference here. A physical theory can make predictions only about things that are of no business interest, so in fact you have to spend money to contrive experimental setups to test it. In contrast, anything that a macroeconomic theory might be making predictions about and that might actually occur in the real world is inherently of business interest. (And again, if you have a counterexample, I'd be curious to hear it.)
For some reason I feel compelled to return to this topic:
My point is not that macroeconomics is a great field filled with great insights (it's not and most macro theorists are terribly confused) but that it's not as ridiculous as you seem to imagine it that some economists have novel, interesting and true things to say about inflation, unemployment, GDP etc and are not themselves fabulously wealthy.
(1) For example, some macroeconomic theories predict behaviors like the parable of the babysitting co-op. You can also run experimental economies (like this) an...
I was immensely glad to find this community, because while I knew intellectually that I was not the only person who felt that rationality was important, death was bad, and technology was our savior, I had never met anyone else who did. I thus determined my career without much input from anything except my own interests; which is not so bad, of course, but I have realized that I might benefit from advice from like-minded people.
Specifically, I would like to know what LessWrong thinks I should do in order to get into "immortality research." Edit: that means "what field should I go into if I want humanity to have extended lifespans as soon as possible?"
I feel immortality, or at least life-extension, is one of - if not the - most important thing(s) humanity can accomplish right now. I don't think I am suited to AI work, however. Another obvious option is an MD, but that's not in my temperament either. My major right now is biochemistry, in preparation for a doctorate in either biochemistry itself, or pharmacology.
I think there's a good chance that advances in this area could contribute to life extension; aging is a biochemical process, right? And certainly drugs will be involved in life extension. But is this the best place to apply my efforts? I have considered that biogerontology (http://en.wikipedia.org/wiki/Gerontology) might be better, as it is about aging specifically; but I don't know much about the field - only that Wikipedia says it is new and very few universities offer degrees in it. My final idea is nanotechnology of some kind; I believe nanomachines may be able to repair our bodies. I'm not sure what type of nanotechnology I'd be looking at for this, or if degrees in it are offered.
Any ideas, suggestions, or comments in general are welcome. I favor the biochemical approach as of now, but only through temperament. As far as I know, AI, biochemical/pharmacological methods, and nanotechnology are all about equally close to giving us immortality. If someone feels one option is better than the others, or has recommended reading on the subject, please share!
Thanks in advance, my new rational friends.