Fermi paradox, your own belief?

(gswork) wrote in message . com...
...
really just looking for opinions, your opinions on why we don't
encounter aliens regularly.

They're made of dark matter :-)

In sci.astro.amateur,rec.arts.sf.science, Michael Ash
wrote:

On Fri, 18 Jun 2004, gswork wrote:

ON the off chance you don't know, Fermi's paradox is basically - if
even conservative estimates suggest that adanced life in the galaxy is
abundant then even more conservative estimates show that the entire
galaxy should be explored already, so why aren't the aliens here?

I don't like the namee "paradox" for this, I think it's too strong
a word for the evidence or lack of. I'd rather think of it as Fermi's
Question [ISTR Carl Sagan polularized it by asking it in his "Cosmos"
TV series], which is simply "Where are they?"
The implication that galaxies should be rainbows/melting pots of
different sentient species which developed in different solar systems
and developed interstellar travel is based on a BOTE calculation using
a lot of "assumed" [and you know what that word means] numbers for the
conditions believed needed for intelligent life to evolve.

various reasons are given as to why they're not : advaned life is
rarer than we thought, space travel is more difficult than we think,
they are here(!), they've put us in quarantine until we grow up,
civilisation destroy themselves at some crucial point etc etc.

Or we may simply be the first. Somebody had to be first, why not us? The
"paradox" holds about as much water as that theory that we must be near
the end of the world because exponential population growth means there's a
95% chance that any given person will be born within a lifetime of the
end, or however it goes.

warning, topic drift

Now, here's an interesting thought, I think I read it at
foresight.org or some other transhumanist writing. Mankind (or any
species) cannot even theoretically continue to grow indefinitely at
its current exponential rate. The exponential will eventually overtake
the cubic volume expansion at the speed of light, so even assuming
there's enough food and other resources, exponential growth will
eventually cause population density to increase even with mankind
expanding at lightspeed in all directions.
But now that I think about this, it fails to take into account the
slowing of time as one approaches lightspeed. (In another blatant
abuse of the word [I'm sure someone, perhaps even Einstein, called it
this, and the name stuck], this is often called the "Twin Paradox"
even though it's not a paradox at all - I always wondered what was
paradoxical about it). Time slows (relative to those stuck on planets
and in freefall) and thus lowers the rate of reproduction, so perhaps
near-lightspeed travel is the only answer for mankind maintaining
"apparent-exponential" growth.

-----
http://mindspring.com/~benbradley

In sci.astro.amateur,rec.arts.sf.science, Michael Ash
wrote:

On Fri, 18 Jun 2004, gswork wrote:

ON the off chance you don't know, Fermi's paradox is basically - if
even conservative estimates suggest that adanced life in the galaxy is
abundant then even more conservative estimates show that the entire
galaxy should be explored already, so why aren't the aliens here?

I don't like the namee "paradox" for this, I think it's too strong
a word for the evidence or lack of. I'd rather think of it as Fermi's
Question [ISTR Carl Sagan polularized it by asking it in his "Cosmos"
TV series], which is simply "Where are they?"
The implication that galaxies should be rainbows/melting pots of
different sentient species which developed in different solar systems
and developed interstellar travel is based on a BOTE calculation using
a lot of "assumed" [and you know what that word means] numbers for the
conditions believed needed for intelligent life to evolve.

various reasons are given as to why they're not : advaned life is
rarer than we thought, space travel is more difficult than we think,
they are here(!), they've put us in quarantine until we grow up,
civilisation destroy themselves at some crucial point etc etc.

Or we may simply be the first. Somebody had to be first, why not us? The
"paradox" holds about as much water as that theory that we must be near
the end of the world because exponential population growth means there's a
95% chance that any given person will be born within a lifetime of the
end, or however it goes.

warning, topic drift

Now, here's an interesting thought, I think I read it at
foresight.org or some other transhumanist writing. Mankind (or any
species) cannot even theoretically continue to grow indefinitely at
its current exponential rate. The exponential will eventually overtake
the cubic volume expansion at the speed of light, so even assuming
there's enough food and other resources, exponential growth will
eventually cause population density to increase even with mankind
expanding at lightspeed in all directions.
But now that I think about this, it fails to take into account the
slowing of time as one approaches lightspeed. (In another blatant
abuse of the word [I'm sure someone, perhaps even Einstein, called it
this, and the name stuck], this is often called the "Twin Paradox"
even though it's not a paradox at all - I always wondered what was
paradoxical about it). Time slows (relative to those stuck on planets
and in freefall) and thus lowers the rate of reproduction, so perhaps
near-lightspeed travel is the only answer for mankind maintaining
"apparent-exponential" growth.

-----
http://mindspring.com/~benbradley

Matthew Ota wrote:

:This is why I do not run the SETI at Home screen saver. I consider it a
:waste of time.

Go with PrimeNet!
:
:Matthew Ota

--
They say there's air in your lungs that's been there for years.

George W. Harris For actual email address, replace each 'u' with an 'i'.

Matthew Ota wrote:

:This is why I do not run the SETI at Home screen saver. I consider it a
:waste of time.

Go with PrimeNet!
:
:Matthew Ota

--
They say there's air in your lungs that's been there for years.

George W. Harris For actual email address, replace each 'u' with an 'i'.

I've read a number of books and papers on this topic, and
I am struck by the large number of quite valid reasons to
expect the current state of affairs, even if there are quite
a few intelligent races in this galaxy besides our own.

My personal favorite explanation is that expansion of
races to planets other than the one they originate from is
much harder than expected, thus limiting the likelihood
of gradual colonization and easier communication.
When left with only the possibility of probes reaching
other populations, myriad problems remain for this being
successful for any given such population.

In any case, keep in mind that all that is needed on one
simple event (among numerous possibilities) for this
"paradox" to evaporate into thin air permanently.

Alan

"gswork" wrote in message
om...
ON the off chance you don't know, Fermi's paradox is basically - if
even conservative estimates suggest that adanced life in the galaxy is
abundant then even more conservative estimates show that the entire
galaxy should be explored already, so why aren't the aliens here?

various reasons are given as to why they're not : advaned life is
rarer than we thought, space travel is more difficult than we think,
they are here(!), they've put us in quarantine until we grow up,
civilisation destroy themselves at some crucial point etc etc.

This is old hat for many, but it may interest or stimulate you. I'm
really just looking for opinions, your opinions on why we don't
encounter aliens regularly.

The one i tend to believe is that whilst life may not be so
overwhelmingly rare, advanced technological space faring life is -
very very rare indeed. So rare it may even be that we are alone in
this galaxy, or maybe sharing with a handful of others dotted around
the milky way, with one each in the magallenic clouds!

I think this because, based on what i've read, Earth has been around
for nearly 5 billion years, microscopic life for perhaps 3 billion,
and more complex life for only 700 million or so. Not only that but
left to it's own devices the Earth would have only another few hundred
million years before the Sun's ever increasing heat output starts to
tip the delicate balance of the eco system and potentially make it too
hostile to complex life, driving life back into the seas, back into
more primitive forms.

A couple of billion years hence, maybe more, the earth tips over into
runaway greenhouse and becomes a milder, but equally deadly version of
Venus, utterly devoid of life. Later still the sun exits the main
sequence, becomes a red giant, and that's pretty much it for the inner
3 planets.

So Earth can support complex life for something like 1.5 billion years
start to finish. It took half that to to get to Humans, and were not
100% sure that we are really a space faring race (in interstellar
terms) or will last long enough to become one. If the dinosaur killer
event didn't happen then there'd be no reason for humans to exist.
Indeed it would only take a series of subtle variations and humans
would not have evolved at all. The evolution of technological
advanced intelligent animals seems really very precarious.

Life itself may be rarer than we think, and space faring life may be
so exceptional that it's more likely we *won't* encounter aliens.

An interesting book on this is Isaac Asimov's 'Extraterrestrial
Civilisations'. It's a 1979 book (IIRC) so the science is
occasionally missing a later discovery or theory, but mostly it makes
sense today and is well written and interesting. (perhaps you have
book recommendations in this area too?)

I've read a number of books and papers on this topic, and
I am struck by the large number of quite valid reasons to
expect the current state of affairs, even if there are quite
a few intelligent races in this galaxy besides our own.

My personal favorite explanation is that expansion of
races to planets other than the one they originate from is
much harder than expected, thus limiting the likelihood
of gradual colonization and easier communication.
When left with only the possibility of probes reaching
other populations, myriad problems remain for this being
successful for any given such population.

In any case, keep in mind that all that is needed on one
simple event (among numerous possibilities) for this
"paradox" to evaporate into thin air permanently.

Alan

"gswork" wrote in message
om...
ON the off chance you don't know, Fermi's paradox is basically - if
even conservative estimates suggest that adanced life in the galaxy is
abundant then even more conservative estimates show that the entire
galaxy should be explored already, so why aren't the aliens here?

various reasons are given as to why they're not : advaned life is
rarer than we thought, space travel is more difficult than we think,
they are here(!), they've put us in quarantine until we grow up,
civilisation destroy themselves at some crucial point etc etc.

This is old hat for many, but it may interest or stimulate you. I'm
really just looking for opinions, your opinions on why we don't
encounter aliens regularly.

The one i tend to believe is that whilst life may not be so
overwhelmingly rare, advanced technological space faring life is -
very very rare indeed. So rare it may even be that we are alone in
this galaxy, or maybe sharing with a handful of others dotted around
the milky way, with one each in the magallenic clouds!

I think this because, based on what i've read, Earth has been around
for nearly 5 billion years, microscopic life for perhaps 3 billion,
and more complex life for only 700 million or so. Not only that but
left to it's own devices the Earth would have only another few hundred
million years before the Sun's ever increasing heat output starts to
tip the delicate balance of the eco system and potentially make it too
hostile to complex life, driving life back into the seas, back into
more primitive forms.

A couple of billion years hence, maybe more, the earth tips over into
runaway greenhouse and becomes a milder, but equally deadly version of
Venus, utterly devoid of life. Later still the sun exits the main
sequence, becomes a red giant, and that's pretty much it for the inner
3 planets.

So Earth can support complex life for something like 1.5 billion years
start to finish. It took half that to to get to Humans, and were not
100% sure that we are really a space faring race (in interstellar
terms) or will last long enough to become one. If the dinosaur killer
event didn't happen then there'd be no reason for humans to exist.
Indeed it would only take a series of subtle variations and humans
would not have evolved at all. The evolution of technological
advanced intelligent animals seems really very precarious.

Life itself may be rarer than we think, and space faring life may be
so exceptional that it's more likely we *won't* encounter aliens.

An interesting book on this is Isaac Asimov's 'Extraterrestrial
Civilisations'. It's a 1979 book (IIRC) so the science is
occasionally missing a later discovery or theory, but mostly it makes
sense today and is well written and interesting. (perhaps you have
book recommendations in this area too?)

(gswork) wrote in message . com...

ON the off chance you don't know, Fermi's paradox is basically - if
even conservative estimates suggest that adanced life in the galaxy is
abundant then even more conservative estimates show that the entire
galaxy should be explored already, so why aren't the aliens here?

various reasons are given as to why they're not : advaned life is
rarer than we thought, space travel is more difficult than we think,
they are here(!), they've put us in quarantine until we grow up,
civilisation destroy themselves at some crucial point etc etc.

Well, my own hunch is that humans will never travel (in person) to
another star. I can give supporting arguments, but obviously that
kind of statement can't be more than a hunch; it can never be proved.

Likewise, I assume that any other intelligent species will come to
the same conclusion -- that travelling to another star is way too
hard, and not worth the hassle. So the physical absence of space
aliens seems totally unsurprising to me.

However, 99% of what could be achieved by actually meeting a space
alien in the flesh could be accomplished over the phone, so to speak,
and at inconceivably lower cost. So it seems to me that the failure
(to date) of SETI indicates a high probability that there is *not*
another intelligent species in our neck of the Milky Way.

Just why is anybody's guess -- in total absence of any evidence,
we are all free to speculate. I give 45% odds that life is
common but rarely becomes multicellular, 45% odds that life is
rare, and 10% odds that Earth is the only place in the entire
universe that harbors life. After all, compared to the combinatorial
improbability of a complex organic molecule organizing itself by
accident, the merely linear vastness of the universe is as nothing.

- Tony Flanders

(gswork) wrote in message . com...

ON the off chance you don't know, Fermi's paradox is basically - if
even conservative estimates suggest that adanced life in the galaxy is
abundant then even more conservative estimates show that the entire
galaxy should be explored already, so why aren't the aliens here?

various reasons are given as to why they're not : advaned life is
rarer than we thought, space travel is more difficult than we think,
they are here(!), they've put us in quarantine until we grow up,
civilisation destroy themselves at some crucial point etc etc.

Well, my own hunch is that humans will never travel (in person) to
another star. I can give supporting arguments, but obviously that
kind of statement can't be more than a hunch; it can never be proved.

Likewise, I assume that any other intelligent species will come to
the same conclusion -- that travelling to another star is way too
hard, and not worth the hassle. So the physical absence of space
aliens seems totally unsurprising to me.

However, 99% of what could be achieved by actually meeting a space
alien in the flesh could be accomplished over the phone, so to speak,
and at inconceivably lower cost. So it seems to me that the failure
(to date) of SETI indicates a high probability that there is *not*
another intelligent species in our neck of the Milky Way.

Just why is anybody's guess -- in total absence of any evidence,
we are all free to speculate. I give 45% odds that life is
common but rarely becomes multicellular, 45% odds that life is
rare, and 10% odds that Earth is the only place in the entire
universe that harbors life. After all, compared to the combinatorial
improbability of a complex organic molecule organizing itself by
accident, the merely linear vastness of the universe is as nothing.

- Tony Flanders

"gswork" wrote in message
om...
ON the off chance you don't know, Fermi's paradox is basically - if
even conservative estimates suggest that adanced life in the galaxy is
abundant then even more conservative estimates show that the entire
galaxy should be explored already, so why aren't the aliens here?


My belief is that Someone much more powerful than even the universe itself
controls it. Therefore, barriers, such as the enormous distance between
stars, were already put in place before the universe was created. There are
certain thresholds that no one will ever cross.

Jon