On 31 Jul, 20:25, Joe Strout wrote:
In article .com,
Ian Parker wrote:

No, I think it will be nornal. Probably if we are the first
civilzation the gap will be of the order of a million years, or at
least 100,000. However you can't be absolutely sure.

You can be very extremely darn close to sure. In a normal distribution,
the spacing between the outliers is quite large (as compared to those
near the mean, which of course is rather small). What "large" means
depends on the standard deviation, but in the case of
time-to-civilization, any reasonable model will result in a standard
deviation of hundreds of millions of years, if not billions.

In that case, the spacing between the two most extreme outliers at one
end of the distribution being a mere 100 KY is quite unlikely. Millions
or billions is more likely.

The model I was
thinking about at the back of my mind was the radioactive atom. It is
not impossible that there could be another civilization close to ours.
Unlikely perhaps, but just possible.

Right. Not sure what radioactive atoms have to do with it, but of
course we can only speak of probabilities. The probability you bring up
here is very, very small.

In my discussions on ET I have sought to eliminate the impossible. NOT
the improbable.

Well, great, but that doesn't help much. It's not impossible that we're
all just figments of the God computer's imagination, which will be shut
off next week. It's not impossible that the our solar system is inside
a vast shell 1 LY across, built by aliens, which serves as a giant 3D
display, and eventually the Pioneer and Voyager probes are going to go
splat against it. It's not impossible that there is some way we can't
yet fathom for advanced races to leave the universe of their birth and
get an entire universe to themselves, thus explaining the apparent
emptiness we see.

But, most of those we can't even assign probabilities too. This one we
can, and it works out to a very small number. (No, I don't have a
number handy; it's been a while since I actually did the math.) Why
focus on such an unlikely situation, when there are far more likely ones
that fit the observations just as well? (Namely, that we're the first,
and our closest competitors are millions of years ahead or behind us.)

I am saying that with a large number competition is more intense and
there might be one near us. We of course don't know. For all we know
Earth could be rare.

It really doesn't matter how many there are; competition won't be more
intense in any case, since all that matters is the first couple of
outliers. If there are many participants, then the outliers will be
more extreme, and thus more spread out. If there are few (i.e. life is
rare), then the outliers won't be as extreme, but they'll still be
spread out.

I feel I'm explaining this poorly... where's a statistician when you
need one?

I will agree that an ET at our level is improbable but not impossible.

Indeed. I believe that well within 50 years we will have a full space
capable Von Neumann machine. An interstellar probe may well be closer
than we imagine. Unmanned of course.

Perhaps. I believe that within 50 years, we'll have mind uploading.
(Ray Kurzweil puts it at more like 20 years, but I am a pessimist.) If
you and I are both right, then those "unmanned" probes may well have
people on board, albeit in digital form.

That is an interesting thought. I have a philosophical point here.
Suppose we split our brains. One bit went to Alpha Centuri. The other
bit went around here on Earth. Could you put those two memories
together? Could two separate memories be knitted together? We could of
course simply back ourselves up when we were about to do anything
dangerous.

A civilization a million years in advance of us, I repeat, is an
impossiblility. We would know about it.

Unless they are intentionally hiding from us. In that case, I have no
doubt that they could do so successfully, and our crude efforts to
detect them would be futile.

But I tend to feel that this is unlikely. More likely, there's simply
nobody out there, and won't be anyone else for millions of years. When
those late-comers finally arise, they'll awaken to a galaxy long since
settled by us and our descendants.

Agreed.

What I have in mind for the medium future is in fact the large
fragmented telescope. Justification - Finding out for sure. I think
Einar is right. If we do not advance it we do not have curiosity we
are indeed doomed. This is not to say that manned space flight is the
best strategy, or that we need to think of colonies in the solar
system in the medium term. In the medium term, and possibly even the
short term, we need to think about improving automation techniques
with an eventual VN aspiration.

I don't agree. VN machines are certainly possible, but I hope they're a
long way off, and carefully regulated. If ever there was a technology
ripe for disaster, that's it. I see very little benefit to justify the
risk.

Are you thinking about the risk that VN machines will evolve, or that
they will be deliberately misused. In terms of evolution, a Reed
Soloman code will prevent evolution in that it will be inpossible for
the VN genome to change.

In terms of misuse, that would depend to a large degree on what the
current political situation was. If you had cognitive AI you could
build in Asimovs laws of robotics and put thise laws as a deeply
encrypted part of the genome. It would not be infallible as once the
knowledge of how to build a VN machine became known one would not be
dependent on one machine. I think I will agree though. We would need a
world that was on the whole peaceful.

BTW - I believe we will get VN machines a long time before brain
downloading. In fact I would probably give that 20 years. What you
basically need for VN is a flatpack assembler. It is downhill after
that.


- Ian Parker