What am I doing? Working for SIAI. For the last hour or so I've been making a mindmap of the effects of 'weird cosmology' on strategies to reduce existential risk: whether or not the simulation hypothesis changes how we should be thinking about the probability of an existential win (conditional on the probability (insofar as probability is a coherent concept here) that something like all possible mathematical/computable structures exist); whether or not we should look more closely at possible inflationary-magnetic-monopole-infinite-universe-creation-horrors; how living in a spatially infinite universe might affect ethics (.pdf warning. Also, I found it a lot easier to think about it as infinite pizza instead of infinite ethics. I don't remember this leading to any significant problems besides a strong desire for pizza. YMMV.); et cetera.
Why am I doing it? I'm not sure if many of these ideas have been compiled into a single place to be synthesized and tested against each other. Weird things happen when you put a recursive 'simulation' in a Tegmark level 4 multiverse with an infinite amount of inflationary universes being formed out of magnetic monopoles with further universes coming into existence at the moment blackholes decohere and then play 'follow the measure' (with a heavy dose of anthropic reasoning, of course). (If someone has done something like this and found interesting results, please let me know, as an hour thinking up crazy stuff does not seem like nearly enough analysis.)
Why do I care about that? It seems like there's a good chance we're missing some much-needed information and it's hidden in a fog of metaphysics. And we really do need it if we want to maximize the probability of a continued humanity.
So what, why does that matter? Well, I love many people and many things, and I would like them to continue existing; and each millionth of a millionth of a percent chance that humanity can live on and flourish, reaching its greatest potential, whatever that may be, is worth whatever effort I can put into it.
That's very interesting. It sounds like you start digging into the problems with level 4 multiverse ethics I plan to write a series of sci-fi novels about. What I have already written (not too much) can be read with Google Wave if you add "our-ascent-noofactory@googlegroups.com" to you contacts and then display the group waves. There are a couple of underlying concepts and questions which come together in my fictional work:
It has been claimed on this site that the fundamental question of rationality is "What do you believe, and why do you believe it?".
A good question it is, but I claim there is another of equal importance. I ask you, Less Wrong...
What are you doing?
And why are you doing it?