[ExI] Silence in the sky-but why?

[Eugen Leitl]

On Sun, Sep 01, 2013 at 04:23:46PM -0600, Kelly Anderson wrote:

> But how many millions of years would it take to get it moving at a
> reasonable speed? Have you done those calculations Spike? I'm sure it
> depends on how many devices you make and how large they are and so forth...
> but assuming you take half the mass of the asteroid belt and build these
> things out of it... what kind of acceleration would you get?

You're competing against relativistic craft ~kg to ~ton range,
capable of 1-10 g acceleration.
 
> The other thing is how would you agree which direction to go? I'm guessing
> humanity would want to move to the outside of the galaxy where the

Humanity that chose to become solid state or begat solid state
will go everywhere it pleases.

> metalicity is higher (more gold, seems like a good reason to go

To astronomers, anything heavier than hydrogen or helium is a
metal. I don't see why you need metals in the chemical sense for, 
other than transition metals, in traces.

> somewhere... LOL) but seriously, how would you figure out the right
> direction to go? Ok, you might be able to compute a good direction with
> regards to the imminent collision with the Andromeda Galaxy... :-)