
Alien life could thrive in ancient star clusters - philbo
http://www.nature.com/news/alien-life-could-thrive-in-ancient-star-clusters-1.19124
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madaxe_again
_Nightfall_ , as mentioned at the end of the piece, is a great little early
Asimov story - a culture to whom candles are alien and the idea of artificial
light is bizarre. Thoroughly recommend. In fact, here it is:
[https://www.uni.edu/morgans/astro/course/nightfall.pdf](https://www.uni.edu/morgans/astro/course/nightfall.pdf)

~~~
4ad
The End of Eternity and Nightfall (the novel with Robert Silverberg, not the
short story) are Asimov's greatest novels.

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pklausler
One argument against the proposition: these very old stars have low
metallicity. If life requires chemistry with elements above lithium in atomic
number, it might be more rare around first-generation stars.

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mercurialshark
I'm always surprised this isn't discussed more or at least a variable to
consider among others for updating the Drake Equation.

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Wingman4l7
Yes; I've often wondered about the potential existence of planets with an
insufficient quantity of rare earth metals, and if that renders them basically
"inhospitable" to high tech civilization.

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erikpukinskis
Why rare earth metals specifically?

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Wingman4l7
They're used for a whole host of technologies -- doping semiconductors,
magnets, lens coatings, metal alloys, etc.

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jtwaleson
"The question is not -where- are the life forms capable of interstellar
communication, but -when- are they."

That is the central point of the argument in the article, yet somehow it's
never really mentioned.

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sawwit
What about gamma ray bursts? I've read that our position more at the outer rim
of the galaxy is beneficial because there are fewer gamma ray bursts compared
to more dense regions.

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pavel_lishin
Aren't most GRBs extra-galactic in origin? If anything, being on the outskirts
means there's less matter protecting us from them.

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Udo
They're only dangerous if they happen within the same galaxy and your planet
happens to be right on the axis of the narrow burst cone. In that case there
might still be a statistical advantage to being nearer to the core of the
galaxy due to more matter density, but it might be offset by the increased
chance of getting hit with a GRB there in the first place.

Also, we're not actually within the outer rim of the galaxy:
[http://www.nasa.gov/mission_pages/sunearth/news/gallery/gala...](http://www.nasa.gov/mission_pages/sunearth/news/gallery/galaxy-
location.html)

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cousin_it
An advanced alien civilization will probably have very low radiation
signature. To afford the maximum amount of computation, it should completely
encase the star (maximum energy) and radiate all waste heat toward a black
hole (maximum cooling).

~~~
Udo
> _and radiate all waste heat toward a black hole (maximum cooling)._

It's comparatively inefficient to radiate heat into a narrow cone, and there
is little advantage to radiating it into a black hole. On the contrary, matter
falling into the black hole will form an accretion disk that radiates heat
back to you. In order to maximize dissipation, they would simply radiate it
away into all directions uniformly.

However, there might be other considerations to take into account here besides
physics. It might be important to such an isolated civilization to avoid
detection. In that case they would gladly take the hit on efficiency and
radiate their heat in narrow cones into the gaps where no nearby stars are
located.

> _An advanced alien civilization will probably have very low radiation
> signature. To afford the maximum amount of computation_

Maybe. We can't say what the goals are of any advanced civilization. The
reason why we like to talk about this _specific_ type of civilization is that
they are the type that we can actually _look for_ right now.

But as I said above, if you're an isolationist population of computer brains,
it makes sense to go through the effort of avoiding other people showing up on
your doorstep. Such a culture might deem it acceptable to invest most of their
energy budget into avoiding detection, as opposed to computation only.

~~~
pavel_lishin
To bring it back to the parent comment, wouldn't it make sense for such a
culture to live near a black hole? All of their waste emissions would be
shadowed pretty well by the accretion disk, and other species might avoid the
neighborhood in general given that it's not a safe or nice place to be.

~~~
Udo
> _wouldn 't it make sense for such a culture to live near a black hole?_

Technically the black hole doesn't offer anything beyond what a sun of
comparable output would offer.

> _and other species might avoid the neighborhood in general given that it 's
> not a safe or nice place to be_

True, but the reasons for avoiding close contact with it are also the reasons
why building a habitat there is potentially risky. All things being equal, a
Mercury-like planet would make a better base for a civilization having those
goals: it offers a lot of solar energy, affords some protection from detection
by being too close to the star to resolve it as a non-natural heat source, and
as opposed to the black hole it's also in a stable environment.

~~~
cousin_it
> _Technically the black hole doesn 't offer anything beyond what a sun of
> comparable output would offer._

Low temperature (lower than cosmic background).

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Udo
If you're really after those 3 Kelvin, you might be happier selecting a host
star that is 3 degrees hotter instead, especially considering the practical
efficiencies of heat exchange systems near absolute zero temperatures.

~~~
cousin_it
If your computer can operate near the Landauer limit, then cooling it to
~10^-7 K makes computing operations cheaper by a factor of ~10^7. Using a 3 K
warmer heat source won't accomplish the same.

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Grishnakh
The thing these speculations about alien life and communicating with them miss
is: what if the aliens don't _want_ to talk to us? That's probably why you
don't hear so much about UFOs these days like we did a few decades ago: they
came, they checked us out, and then they launched some beacons just outside
our solar system warning everyone to stay away, along with a Galactic General
Order that if we ever develop enough to send manned missions outside our
system, we have to be destroyed for the good of the galaxy.

~~~
Udo
There are two propositions here:

One, that some UFO sightings are due to the activities of extraterrestrial
intelligences. This seems very unlikely at this point.

Second, that the Fermi Paradox exists at least partly due to aliens avoiding
us specifically, what is commonly referred to as the "zoo hypothesis". As far
as speculative explanations go, it's not an unreasonable contender. However,
it is not among the most likely or the most simple hypotheses out there.

The zoo hypothesis pre-supposes the ready availability of FTL technology,
which itself implies that such technology is even possible in general. It also
hinges on a specific combination of psychological factors and random
happenstance, namely the desire to isolate an entire star system (which is not
a trivial feat), and the fact that they even discovered our existence in the
first place (which is also quite the coincidence, even for a culture that can
travel faster than the speed of light).

These reasons don't rule out the zoo hypothesis. However, if I were to bet on
one scenario, it would be the practical consequences of the fact that expected
distances between civilizations are enormous in both time and space, plus the
weakly-shining light cone of our technologically advanced existence doesn't
reach very far and isn't easy to detect - and those same factors would be
preventing us from seeing an advanced civilization as well, even if they
happened to be relatively close by.

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trhway
>Second, that the Fermi Paradox exists at least partly due to aliens avoiding
us specifically, what is commonly referred to as the "zoo hypothesis". As far
as speculative explanations go, it's not an unreasonable contender. However,
it is not among the most likely or the most simple hypotheses out there.

even we, Earthicans, can learn from Columbus visiting America and the
following fate of civilizations there. Any higher developed civilization
definitely has "zoo"/Prime Directive principle in place.

A technological civilization stage between start of building machines
(Industrial Revolution in our case) and FTL (and thus also leaving EM related
tech behind) is pretty short, thousands, may be tens of thousands of years -
absolutely not enough to have overlaps between tech civilizations to
listen/watch radio/TV of each other.

>The zoo hypothesis pre-supposes the ready availability of FTL technology,
which itself implies that such technology is even possible in general.

well, far galaxies run away from us at speeds higher than FTL, so it is
possible. Space expansion is different machinery and not subject to "c" limit
(that limit is only valid against static space)

~~~
Udo
> _may be tens of thousands of years - absolutely not enough to have overlaps
> between tech civilizations to listen /watch radio/TV of each other_

From what we know, that is a reasonable assumption.

> _Space expansion is different machinery and not subject to "c" limit (that
> limit is only valid against static space)_

The expansion of the universe and rapidly-increasing distance to far galaxies
is not a good example, but yes, the "limit" of c is only applicable to static
space. And you are right in the sense that the Hubble flow is an example of
objects changing their relative positions without momentum being the primary
component.

As I like to frame it: in day-to-day life we are used to define "travel" as
accelerating matter to a certain velocity until we reach a destination point.
However, acceleration is not the goal of travel: being at the destination
point itself is the goal. For example, travel through an artificially
shortened corridor of spacetime would still be a valid form of FTL even though
acceleration itself never reached relativistically relevant levels.

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cnp
One thing that always surprises me about the search for ET is how often the
purely psychological / consciousness aspect is disregarded. As anyone who has
worked with DMT or Ayahuasca can tell you, you don't need to travel far to
reach the outer limits of space or even have contact experiences, and this is
very easy to test should the anti-scientific legal mechanisms preventing such
a study be overcome.

Its like, Fermi's Paradox is almost completely irrelevant if you come from the
position that any sufficiently advanced civilization is aware of the possible
non-local properties of consciousness.

~~~
Udo
> _As anyone who has worked with DMT or Ayahuasca can tell you, you don 't
> need to travel far to reach the outer limits of space or even have contact
> experiences_

The effects of drug-induced illusions _are_ scientifically interesting to a
number of research fields, including biochemistry and neurobiology. It may
also be valuable for self-discovery and personal actualization. However, if
you claim to be able to discern cosmological facts from these experiences, we
are now firmly in the realm of religion.

> _and this is very easy to test should the completely anti-scientific legal
> mechanisms preventing such a study be overcome_

There have been a lot of studies testing supernatural powers, with and without
the influence of drugs, in the sixties and seventies. None of these have ever
yielded anything. But if it's very easy to test, as you claim, then go ahead
and test it. The James Randi foundation offers a sizable prize for you if you
can show this works:
[https://en.wikipedia.org/wiki/One_Million_Dollar_Paranormal_...](https://en.wikipedia.org/wiki/One_Million_Dollar_Paranormal_Challenge)

~~~
cnp
I'm not claiming anything, I'm saying: its possible that there is more to
consciousness than it appears and that the barriers to studying the
relationships between certain tryptamine compounds and the human psyche is a
worthy scientific endeavor to overcome. All I can speak to are my own
_personal_ experiences, and those who participated in Rick Strassman's DMT
study between 1990 and 1995 at the University of New Mexico.

If you don't mind me asking, how is this not clear?

~~~
Udo
> _I 'm not claiming anything, I'm saying: its possible that there is more to
> consciousness than it appears_

That is not correct. In the post above you said, literally, " _you don 't need
to travel far to reach the outer limits of space or even have contact
experiences [...] Its like, Fermi's Paradox is almost completely irrelevant if
you come from the position that any sufficiently advanced civilization is
aware of the possible non-local properties of consciousness_". That's a claim.

I think it's fair to conclude you are _not_ assigning an extremely _low_
probability to there being " _more to consciousness than it appears_ ".

> _studying the relationships between certain tryptamine compounds and the
> human psyche_

This is a purely biological endeavor. The reason why I responded to your
earlier post, and also the reason why this even shows up in a thread about
planet formation, is that you claim to be able to explore the cosmos by
ingesting mind-altering substances.

> _All I can speak to are my own personal experiences._

For what it's worth, nobody is disputing you had these experiences. What is in
dispute is the claim that these experiences yield scientific facts by virtue
of remote viewing.

~~~
cnp
Ok let me clarify my position completely so that there is no dispute, and then
I need to get back to work:

Formal and informal study participants have noted that when you ingest
N,N-Dimethyltryptamine certain strange contact-like phenomena tend to occur
within the biological-psychological interface known as Consciousness, and that
these experiences -- which have an internal consistency -- seem to be
inexplicably independent of culture, background or time. These contact
experiences were so shocking that the lead investigator, Rick Strassman,
discontinued his study. Meanwhile, nearly 20 years later, there are still
legal barriers in place for the further study of these results due to the War
on Drugs. My position is: the phenomena -- based upon my own personal
experience -- is deeply strange, and in when put within the context of Fermi's
Paradox, the Drake equation, etc, it might be time to approach the subject of
consciousness from a different angle. Its so simple, its merely _to
investigate_.

~~~
Udo
> _when you ingest N,N-Dimethyltryptamine certain strange contact-like
> phenomena tend to occur_

That's not in question.

> _occur within the biological-psychological interface known as Consciousness_

This sentence includes a little submarine-like assumption, namely that our
brains are merely the interface to a larger paranormal consciousness, as
opposed to being the hardware that actually generates "consciousness". At this
point, there is no scientific reason to believe this assumption which you
smuggled in there has any factual validity.

> _These contact experiences were so shocking that the lead investigator, Rick
> Strassman, discontinued his study._

Scientific efforts don't get discontinued because they are "shocking". While
an individual researcher might move on, for _whatever reason_ , it's not
correct to imply that certain outcomes are so disconcerting the scientific
community would shy away from them. Otherwise, large swaths of physics and
biology would have been abandoned a long time ago.

> _My position is: the phenomena [...] is deeply strange, and [...] it might
> be time to approach the subject of consciousness from a different angle._

Yes, I think that position was understood from your first comment.

