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The Fermi Paradox

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Re: The Fermi Paradox

#141

Post by JoeAltmaier »

fernly wrote: post #140
wavesum wrote: post #58

I think the biggest fallacy in this rationalization is when it is assumed that advanced civilizations would want to expand like yeast; consuming everything, building dyson spheres... Why would they want that much energy, and why extract it from the sun? Trying to picture myself as one of these superlifeforms, I think would like to have the sun visible... For sunbathing and sh ... plants to grow etc... Maybe they have…

The SUN is visible everywhere within a Dyson sphere; it's the STARS that you can't see any more. The idea isn't that a civilization wants to do this; the idea is that it needs that much energy to continue with whatever industrial or infrastructure processes it requires to support a very large population. Dyson reasoned, we need steadily increasing amounts of energy input to support what we are doing; if the trend con…

I always thought that was a primitive notion. We can build the sphere, but not control the star? Imagine a caveman - "Limit to civilization when all energy from campfire captured - most people warm, most meat cooked" Clearly one can do better than a campfire.

Instead, imagine harvesting energy from the star asymmetrically - from flares or from the inside out. Or get your energy from a neighboring star. Or make your own star. Or whatever a Type-whatever civilization decides to do.

Re: The Fermi Paradox

#142

Post by mickdarling »

DavidSJ wrote: post #89
mickdarling wrote: post #83

Earlier quoted context omitted.

Two Scifi examples that come to mind are a book, GreenFlies ( http://www.amazon.com/Greenflies-Andrew-Darling-ebook/dp/B00... ) that has a fun example of a super-predator type-3-ish civilization, and the motivations that would create the galaxy we see today. David Brin also has a great book, Existence ( http://www.amazon.com/Existence-David-Brin-ebook/dp/B0079XPM... ), that is an example of a super-predator meme that…

That seems different to me. There's lots of scifi and speculation about contact between civilizations of vastly different technological development. But the idea here is that the expansion of a civilization happens so quickly that it consumes all the resources around it before other civilizations get a chance to exist at all. No malevolence ("superpredators") required. The probability that a new civilization is born…

Super-predator Civilizations solve the significant problem of blaming the silence on a psychological quirk rather than statistics.

When you are making assumptions about the millions of civilizations, it is absurd to think they ALL retreated to playing video games for eternity, or ALL nuked themselves to oblivion.

With a single super-predator civ, that has a huge leg up on everyone else, they can have unusual motivations, and techniques. The problem with a super-predator is you likely won't be able to learn anything to prove or disprove them until you meet them, with all that implies.

Re: The Fermi Paradox

#143

Post by JoeAltmaier »

maaku wrote: post #10

The "we are the first" argument seemed less convincing than it could have been. A better argument from that perspective is the observation that Type III civilizations expand at an alarming rate. Whatever the motivation for expansion[1], basic simulations and back of the envelope calculations show that even with technology we could imagine building in the not so distant future, humans could expand into the cosmos at >…

Speed of light is fast enough, considering how long the universe has been around. Our galaxy is 100 thousand light-years - a blink in geological time. We can see everything that ever happened in our galaxy right now, excepting the last few moments.

I'd instead be looking for evidence civilizations are expanding by ways we don't yet suspect. Soliton waves through gas clouds? Wormholes? Multidimensional folds? What would those things look like? Maybe they look like dark matter or something.

Re: The Fermi Paradox

#144

Post by JoeAltmaier »

_greim_ wrote: post #23
gpsx wrote: post #6

This article does a good job of covering a lot of different ideas on this paradox. I have a problem with the idea of "big numbers" in it though, like where it implies 500 billion billion is nearly infinite, or that one-in-a-billion is a freak occurrence. There is a saying that if enough monkeys pound on a keyboard, one will type Hamlet. This would take a lot of monkeys. If we take the odds of hitting one character to…

We can't calculate the probability of life arising though because even if we did know how it arose here—which we don't exactly—we don't know all the possible different ways it can arise, which may or may not also be a number raised to a large power.

I've always thought, given the right circumstances, life will always be formed. Instead we should be calculating the odds of life NOT forming e.g. the half-life of staying-dead.

Our planet has carbon, oxygen, water, the right temperature, a moon that sloshes it all around, rotation. Every grain of sand on every beach is going through a different cycle of heating/cooling + wetting/drying + different salts and ions depending on the local environment. For a billion years it was this enormous biochemistry experiment. Life pretty much HAD to happen, somewhere in all that.

Re: The Fermi Paradox

#145

Post by sgt101 »

handojin wrote: post #79
sgt101 wrote: post #38

Earlier quoted context omitted.

I've read a novel that featured this, I am wracking my brains to remember the title/author. It featured a generation ship that switched to a .com mode as it approached the star to be colonized and a race of bat people who were the putative colonization targets. I am not making this up, but I may have dreamt it!

Nope. Ken MacLeod's 'learning the world'. The alien space bats were a nice touch. Charles Stross' book accelerando has an interesting take on the Fermi paradox too.

Yup, that was the one. Thanks!

Re: The Fermi Paradox

#146

Post by DougN7 »

The idea that maybe aliens visited before humans could record what they experienced struck me. Even if they did record it, we wouldn't believe it. Need proof? See the Bible or virtually any other ancient religious text. Our modern society believes if we can't prove it today, it didn't happen.

Re: The Fermi Paradox

#147

Post by sgt101 »

tomp wrote: post #61
sgt101 wrote: post #43

Earlier quoted context omitted.

This is one explanation, but for me fails two tests. The first (pointed out below) is that it is heliocentric - it's about us. The second is that it avoids freedom of will and consciousness in the sense of self perception. It assumes that I am a zombie, and I deny that. I concede that others may be zombies, although I think that they aren't. My actions either navigate me from state to state or create new states. Phys…

What does "freedom of will" mean to you? What you describe (actions move you from state to state) sounds like determinism to me.

To decide which state to move to. That I (and others) are agents that change the future of the universe by choice within the frameworks of possibility.

Re: The Fermi Paradox

#148

Post by maaku »

sampo wrote: post #125
maaku wrote: post #110

Earlier quoted context omitted.

Meh, it's a long way from saying that "we don't know how the O2 could have been produced except by life" to "the O2 was produced by life." Just look at the current debate about methane on Mars.

In a 1993 article, Carl Sagan considered the atmospheric oxygen content "at least suggestive of biology" (Conclusions, 3rd paragraph). http://www-pw.physics.uiowa.edu/~dag/publications/1993_ASear...

Am I supposed to disagree with that? High atmospheric oxygen content is suggestive of biology. So is seasonal blooms of methane on a planet like Mars. Is that suggestive that there is life on Mars? Yes! Can we definitively infer that there is presently life on Mars? Not yet.

Re: The Fermi Paradox

#149

Post by adventured »

drjesusphd wrote: post #112

I personally find the "we are first" solution to be the scariest scenario. We are not suited for the responsibility of being the only intelligent life in the universe.

What responsibility? I can see absolutely zero responsibility attached to that scenario.

Humans also may be the most responsible intelligent life that ever exists in the universe. What's the basis to judge such things to begin with?

There's an exceptionally low probability that human survival has any bearing on whether other intelligent life comes to exist (in the we're first scenario). Being first bears no responsibility because future life in the galaxy or universe is not inherently dependent on what we do.

Re: The Fermi Paradox

#150

Post by danieltillett »

darkmighty wrote: post #129
danieltillett wrote: post #56

Earlier quoted context omitted.

I actually posted about this very topic a few days ago here. Once you have von Neumann machines spreading they will take over each new star system pretty much as soon as they reach it. Assuming the von Neumann machines are small and are being powered by an energy source (i.e lasers) from their origin star system they will spread through the galaxy at close to the speed of light. This spread method creates an interest…

Interesting. Just a note: it probably wouldn't seem as if a chunk of the galaxies was removed; in fact, I believe the luminosity (after some settling time) of a start with a Dyson sphere or the like would emit about the same light a regular star does -- the difference would be the temperature. The apparent temperature of the star should increase(?) (i.e. it emits(?) higher entropy radiation): by simple energy conserv…

Such galaxies already exist [1]. They appear to be natural, but who knows for sure.

The temperature of the Dyson Sphere will determine the wave length the star apears to shine at. If the sphere is designed to capture the maximum energy possible then the temperature will be close to the cosmic background radiation temperature (2.73K) and so would be very hard to detect.

1. http://en.m.wikipedia.org/wiki/Luminous_infrared_galaxy

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