[ExI] The Great Silence again

[Keith Henson]

On Tue, Apr 26, 2011 at 12:56 PM, Eugen Leitl <eugen at leitl.org> wrote:
> On Tue, Apr 26, 2011 at 08:42:05PM +0100, BillK wrote:
>> On Tue, Apr 26, 2011 at 8:25 PM, Eugen Leitl  wrote:
>> > No, they will result in a huge canvas of culture cells. Just as
>> > today's Earth, only much, much larger.
>> >
>>
>> But invisible and not changing any natural bodies in the galaxy.
>
> They're about as invisible as Tsar Bomba from a few km
> distance. The observation window is very short.

That's a very good point, if the maximum speed of expansion is close
to the speed of light, you would not see a hole punched in a galaxy
before the hole punchers were in your lap.  If the speed of expansion
is much slower, you could see them for a while before they got to you
and went *munch*.

>> Do you think they exist outside your imagination?
>
> You being able to write this message is the best
> proof that we're not in anybody's smart lightcone.

Good point.

> In fact, the best way to observe an expansion is
> to be the nucleus; anthropic principle.

Possibly the only way.

>> The whole galaxy could easily have been colonised by now even at low
>> sub-light speeds if they wanted to. We are late arrivals.  These
>> invisible civilisations haven't done too well at expanding up to now.
>
> The entire galaxy is colonized by invisible pink unicorns.

If we really are late arrivals, then chances are we are as doomed as they were.

Keith