Rob Dekker wrote:

"Martin Andersen" <martin@al-data.dk> wrote in message
news:41ab3773$0$156$edfadb0f@dtext02.news.tele.dk...
[.....]

Such information could be retrieved by sending a probe spaceship, capable

of

observing, doing calculations and communicating. A probe like this could
be smaller
than a grain of sand !

Interesting ideas, but there are a few theoretical limitations to
miniturization.

CUT

Thanks for posting ! I agree with your points, they seem to be valid.

The ideas are work in progress, of course. My plan is to use Kurtzweil's
thinking about our technology, and transfer it to alien civilizations.

I postulate: Kurtzweil's accelerated returns for technology is an universal
law, applicable for any technological civilization, not just ours.

What would it mean ?
First of all, if there are civilizations out there, they are likely to be way ahead
of us, since their technology will grow exponentially, according to Kurtzweil.

Assuming: There are civilizations out there capable of traveling to earth, not just
one but several independent.
It's important to reflect over what they have in common.

1. They are all capable of building a spaceship which can travel to earth. Naturally,
since that's an assumption made.

2. Nanotechnology, they can manipulate matter atom by atom. Humans are a few
years from doing this.

How would these aliens live ? They would have solved all their problems like lack of food,
diseases and energy sources. They have build their world just like they want it.
The solarsystem they live in have more than enough materials for their needs.

Such a civilization, could it be interested in emmigrating to earth ? To conqueror earth
and kill us all ? The answer is no. If you had everything you needed, would you travel
far far away to an uncertain destiny ? Of course not.

It has everything, except for one thing: Information about other planetary systems.
As us, they have detected other planets, they have measured spectral lines
in the planets, maybe even observed earth, build large complex computer programs
to simulate them in detail. Even then, no matter how advanced they are, they can't
know for sure how it looks on other planets, they need to go there.

Information is the only interesting thing for these creatures, it would be a high priority
to explore other worlds. How ? They would send a probe. As mentioned in the post by
Dekker, they can't send a probe the size of a grain of sand or smaller, since it
couldn't observe anything or transmit back data. So it needs to be about 10 meters in size.

Sending a probe that large could be a security risk if it falls into the wrong hands.
So they would send a stealth-probe, undetectable by radar or other means.
This point is not critical in solving the Fermi paradox. Critical is that the aliens
only want information, they don't want to talk to us or kill us.
They could send a spaceship the size of the moon and place it just outside Pluto's orbit, we wouldn't
see it. But why do that when you can ship something way smaller ?

Conclusion:

As of now, I see 2 solutions to Fermi's paradox:

1. We are alone in the Galaxy.

2. There are some highly advanced civilizations out there, only interested in observing, gathering
information. They will not transmit any signals to us, but send probes out to collect data.
We humans can't detect these aliens (yet), SETI will hear nothing.
But the law of accelerating returns is valid for human technology, soon we will detect them, either
by extremely large optical telescopes, or by sending probes.

Martin.