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The Great Filter – Are We Almost Past It? (1998)

mason.gmu.edu

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Re: The Great Filter – Are We Almost Past It? (1998)

#41

Post by exratione »

Udo wrote: post #4

There is a disconnect between these two statements: " No alien civilizations have substantially colonized our solar system or systems nearby. Thus among the billion trillion stars in our past universe, none has reached the level of technology and growth that we may soon reach. " While the article is in a way all about exploring that disconnect, it's a bit strange to find it written down so explicitly in the conclusio…

The problem is that if you exclude the scenarios that obviously didn't happen you are still left with no likely scenarios given the present consensus understanding of biology and physics.

The timescale for megascale engineering to occur throughout our galaxy as the result of the launch of one megascale engineering minded self replicating probe is small (1 million years) in comparison to the age of the galaxy (13 billion years). It is unlikely that we are sitting here while someone else is in the process of doing it; that's not the scenario to focus on.

All it takes, remember, is one small group in one sufficiently advanced culture to start this going. Some (post)human group will clearly do it at some point if we as a species continue. Why hasn't someone already done it, where "it" is visibly engineer the totality of the future light cone?

The problem is less one of why don't we see Dyson spheres and other similar type II projects within a few hundred light years of our position, and more one of why do we see no obviously altered galaxies among the hundreds of thousands cataloged to date. At this scale the zoo hypothesis looks stretched, and the simulation argument begins to look more plausible.

Re: The Great Filter – Are We Almost Past It? (1998)

#42

Post by jimmcslim »

facepalm wrote: post #29
api wrote: post #10

We are provably not beyond the great filter. At least one great filter lies tangibly in front of us: ecological sustainability. Barring several fairly large changes to our energy and resource systems, our civilization is mathematically and physically guaranteed to collapse within the next 200 years at most. That's not a hypothetical filter. It's a real one that we can see, and we are not past it.

A lot of people might die, but that alone doesn't imply that civilization goes away.

Maybe intelligent ife is the universe is in fact quite abundant, but having followed the trajectory we are on and exhausted all its natural resources that would support becoming extra-solar civilisations, they collapse back to simpler, less technological agrarian societies?

Re: The Great Filter – Are We Almost Past It? (1998)

#43

Post by exratione »

thesteamboat wrote: post #28
PeterWhittaker wrote: post #6

We suffer from hubris when we label it the "Fermi paradox ": It implies that somehow we are interesting, worth visiting. If we are, it may well be as a cautionary tale or for tourism. Consider the energy and material engineering necessary to achieve long-distance space transport of any sizable amount of people, equipment, and supplies. Regardless of whether the transport is subluminal or FTL, the energy requirements…

"No one wants to talk to us" is not a sufficient explanation. We need to be able to explain why we don't observe any stellar engineering. Assuming alien civilizations they either 1) can't make use of the most prominent energy sources around, 2) choose not to for some reason, or 3) we can't detect what they're doing. 1 and 2 don't make sense if you assume that there are many alien civilizations older and more advanced…

Astrophysics is as solid as particle physics and plasma physics; it's the other laboratory used to confirm fundamental theory. The models are very good. There is a natural explanation for every well observed phenomenon that fits all known physics, and wherein the models match up to the observations. Astrophysics really isn't the place to be looking first for issues, I'd say.

Re: The Great Filter – Are We Almost Past It? (1998)

#44

Post by radicalbyte »

thesteamboat wrote: post #28
PeterWhittaker wrote: post #6

We suffer from hubris when we label it the "Fermi paradox ": It implies that somehow we are interesting, worth visiting. If we are, it may well be as a cautionary tale or for tourism. Consider the energy and material engineering necessary to achieve long-distance space transport of any sizable amount of people, equipment, and supplies. Regardless of whether the transport is subluminal or FTL, the energy requirements…

"No one wants to talk to us" is not a sufficient explanation. We need to be able to explain why we don't observe any stellar engineering. Assuming alien civilizations they either 1) can't make use of the most prominent energy sources around, 2) choose not to for some reason, or 3) we can't detect what they're doing. 1 and 2 don't make sense if you assume that there are many alien civilizations older and more advanced…

What if "dark matter" is actually stars enclosed in dyson spheres? http://en.wikipedia.org/wiki/Dyson_sphere

Re: The Great Filter – Are We Almost Past It? (1998)

#45

Post by krapp »

jeremyjh wrote: post #27
tomjen3 wrote: post #5

I forgot who came up with the idea, but the great filter may not exist - it is just that an intergalactic civilisation wouldn't be using radio communication (due to the lag because of the slow speed of light). Or the put it a bit different: unless the Culture want us to see it, we won't.

Why aren't they building Dyson spheres?

Maybe it turns out Dyson spheres are a bad idea for some reason? Maybe Dyson spheres are out there, but constructed in such a way that they don't look obvious to a distant observer? Maybe the idea that advanced civilizations exponentially consuming energy as per the Kardashev Scale is a flawed and anthropocentric premise based entirely on what we know of our own civilization, and a lack of observable stellar engineering doesn't necessarily mean a lack of advanced life?

Re: The Great Filter – Are We Almost Past It? (1998)

#46

Post by thesteamboat »

exratione wrote: post #41
Udo wrote: post #4

There is a disconnect between these two statements: " No alien civilizations have substantially colonized our solar system or systems nearby. Thus among the billion trillion stars in our past universe, none has reached the level of technology and growth that we may soon reach. " While the article is in a way all about exploring that disconnect, it's a bit strange to find it written down so explicitly in the conclusio…

The problem is that if you exclude the scenarios that obviously didn't happen you are still left with no likely scenarios given the present consensus understanding of biology and physics. The timescale for megascale engineering to occur throughout our galaxy as the result of the launch of one megascale engineering minded self replicating probe is small (1 million years) in comparison to the age of the galaxy (13 bill…

Your comment sparked an interesting question in my mind: If some entity is trying to colonize in every direction at near the speed of light what is the expected gap time between the light of the actions reaching us and them reaching and colonizing us?

A partial answer to the Fermi paradox by appeal to the anthropic principle: there is a very small fraction of time between being able to observe an alien species and being consumed by it.

Re: The Great Filter – Are We Almost Past It? (1998)

#47

Post by thesteamboat »

exratione wrote: post #43
thesteamboat wrote: post #28

Earlier quoted context omitted.

"No one wants to talk to us" is not a sufficient explanation. We need to be able to explain why we don't observe any stellar engineering. Assuming alien civilizations they either 1) can't make use of the most prominent energy sources around, 2) choose not to for some reason, or 3) we can't detect what they're doing. 1 and 2 don't make sense if you assume that there are many alien civilizations older and more advanced…

Astrophysics is as solid as particle physics and plasma physics; it's the other laboratory used to confirm fundamental theory. The models are very good. There is a natural explanation for every well observed phenomenon that fits all known physics, and wherein the models match up to the observations. Astrophysics really isn't the place to be looking first for issues, I'd say.

I don't really know enough about physics to be able to judge, but what you say is nicely in accordance with my priors. I think we're in agreement here. I wouldn't argue that 3 was the place the argument most likely fails, merely that there is something here that we don't fully understand and which may be rather important -- hence it's reasonable to call it a paradox.

Re: The Great Filter – Are We Almost Past It? (1998)

#48

Post by Udo »

exratione wrote: post #41
Udo wrote: post #4

There is a disconnect between these two statements: " No alien civilizations have substantially colonized our solar system or systems nearby. Thus among the billion trillion stars in our past universe, none has reached the level of technology and growth that we may soon reach. " While the article is in a way all about exploring that disconnect, it's a bit strange to find it written down so explicitly in the conclusio…

The problem is that if you exclude the scenarios that obviously didn't happen you are still left with no likely scenarios given the present consensus understanding of biology and physics. The timescale for megascale engineering to occur throughout our galaxy as the result of the launch of one megascale engineering minded self replicating probe is small (1 million years) in comparison to the age of the galaxy (13 bill…

Good points, but I'd like to offer some counter arguments to the megascale engineering idea, hopefully without sounding too pedantic.

The need for megascale projects is not as obvious as it's sometimes made out to be. There might well be reasonable limits beyond which the maximizing of habitat space and energy consumption tapers off in utility. Even if our civilization continues on its present course, it's not certain that we will get to the point where we (or some of us) feel the need to change the face of the galaxy. If you go one step down from the galactic stage, the detectability of solar system-scale megatech is also open to debate, especially as you move beyond a couple hundred light years from here.

You're right of course when you say all it takes is one civilization (or even one member of a sufficiently advanced society) to undertake projects that are liable to make all kinds of strange phenomena appear in our night sky. But the number if beings capable of doing so on a whim, multiplied by the chance they'd be interested in such things, might be very very small without breaking any of our current expectations about biology and physics.

Finally, I'd like to address the simulation argument. There are two extreme ends of the simulation scenario spectrum.

At the one extreme, we're talking about an artificial reality made especially for us, humans. This would be the popular "Matrix"-style simulation. No scientific argument I've heard so far makes it a convincing model for the reality we live in, except as a possible explanation for the Fermi paradox.

At the other end of the spectrum, we have a full simulated universe. It's hard to argue for or against that notion, simply because either way it fits with our observable reality. The catch is of course that it's a neutral proposition with no impact on us at all. This variant does not offer any explanation for the Fermi paradox.

As I see it, the simulation argument as pertinent to the Fermi problem offers two options, neither of which are intellectually appealing: one is a borderline-untenable just-so make-believe world where all rules are an illusion and anything can happen, and the other one is virtually undistinguishable from our "normal" world, up to and including an absence of any obvious explanation for the Fermi paradox.

Re: The Great Filter – Are We Almost Past It? (1998)

#49

Post by guard-of-terra »

jeremyjh wrote: post #27
tomjen3 wrote: post #5

I forgot who came up with the idea, but the great filter may not exist - it is just that an intergalactic civilisation wouldn't be using radio communication (due to the lag because of the slow speed of light). Or the put it a bit different: unless the Culture want us to see it, we won't.

Why aren't they building Dyson spheres?

Maybe there's a lot of lower hanging fruits in the galaxy energy-wise than building Dyson shperes.

Re: The Great Filter – Are We Almost Past It? (1998)

#50

Post by Retra »

Udo wrote: post #20
Retra wrote: post #13

Earlier quoted context omitted.

The 'soonness' of our interplanetary colonization is really not safe to assume. The obstacles to self-sustaining life on other worlds are not insignificant -- in fact, they are the explanation for why there is no life there to begin with.

You are certainly correct - but did I imply otherwise in my comment..?

No, I was agreeing with you on a parallel point.
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