[ExI] Perception of time was Wrestling with Embodiment

[Eugen Leitl]

On Tue, Jan 24, 2012 at 09:32:15AM +0000, BillK wrote:
> On Tue, Jan 24, 2012 at 8:02 AM, Eugen Leitl  wrote:
> > We're not in anybody's smart light cone. Galaxy has nothing to
> > do with it.
> >
> 
> Irrelevant. We don't need to be in anyone's light cone.  The age of

Relevant. In order to be able to be aware of any event
you need to be in that event's lightcone. 

In case of relativistically expanding cultures they're
hugging their light cone (counted from the moment they've
become expansive and hence observable) pretty closely.
(There's some set up time, but it's short).

Which means the delay between observability and arrival
(and elimination of observer, unless observer is also
expansive) is short. Try observing a bullet fired at
your head across the room. Your chances are better
if you watch a sniper from km distance so you see the
muzzle flash before the bullet arrives and removes the
observer's ability to observe.

> the galaxy means that the whole galaxy should already have been swept
> many times over by waves of expanding species.

If it was you wouldn't be able to read this message.
So by writing it you've proved above didn't happen.
 
> > Relativistic travel is easy, so any expansion will become
> > relativistic after a few hops latest by way of self-selection
> > of front organisms.
> >
> 
> Agreed. So where are they?  We are a very young species compared to
> the age of the galaxy.

Again, we can only see the expanding kind, and even then
not very well (because they then eat you). The best explanation
for "where are they?" is that they're not there yet. 
Same applies for us eating other hatchling aliens.

This strikes people as improbable, but statistics doesn't
work in a perfectly biased self-observation sample, so the
only information you have is that there's at least one
instance of you.
 
> Either we are are the first in the galaxy, or after relativistic

The galaxy has nothing to do with it, it's a question of
how soon somebody could have hatched, considered metallicity
and setup time for sufficient evolutionary complexity in
absence of sterilizing events. That number is arguably
gigayears, so a lot bigger than just one small dinky galaxy.

> travel becomes possible for some reason civs don't expand.

If there are two explanations: there is nobody, so you're 
observing nothing, or there are many, and *all* of them 
(this is now a statistical argument) are non-expansive, then
pick the branch Occam suggests to you.

I think we're just lucky.