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Beyond “Fermi’s Paradox” XVI: What Is the “Dark Forest” Hypothesis?

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Re: Beyond “Fermi’s Paradox” XVI: What Is the “Dark Forest” Hypothesis?

#211

Post by ping_pong »

AnIdiotOnTheNet wrote: post #45
bobcostas55 wrote: post #24

Earlier quoted context omitted.

>because it assumes that projecting power over interstellar distances is easier than defending yourself This seems really obviously true to me. Accelerating a rock to relativistic speeds is pretty easy, defending against a rock potentially coming from anywhere in space traveling at relativistic speeds is extremely difficult.

1) I think you're underestimating the difficulty of accelerating any massive object to relativistic speeds, 2) doing so with enough accuracy to hit a relatively small moving target many light-years away is not exactly trivial, 3) a civilization with the capability to accelerate a massive object to relativistic speeds is probably also capable of building self-sufficient artificial habitats around its star, which is a…

You're definitely not thinking creatively enough.

You don't need to hit the planet directly with anything, all you need to do is destabilize the orbit of all the planets or even just the Earth itself. You could send a gravity wave for example, that would cause the Earth's near circular orbit to shift to a very eliptical orbit. The vast change in temperatures would kill all life on the planet, and then you could come and mine all the resources that you needed and leave.

Re: Beyond “Fermi’s Paradox” XVI: What Is the “Dark Forest” Hypothesis?

#212

Post by artimaeis »

jmull wrote: post #139

I love that series -- just an incredible, imaginative, unique perspective -- but the dark forest hypothesis just doesn't make sense. It's orders of magnitude of orders of magnitude less energy to communicate with (including obscuring your origin, if you want) than destroy a civilization. And communication has potential benefits (cooperation) that destruction does not. Civilizations that communicated would very quickl…

I also adore the series. It's become my favorite sci-fi I've read in years.

You're leaving out the time required to communicate. Yes, communication would require less energy, but time is a constant that even type 3 civilizations could be in short supply of.

The chain of suspicion calls this out explicitly, it's not that the civs cannot communicate, it's that due to the extreme lengths of time required for back-and-forth communications their societies are likely to significantly change during communications, leading to higher probability of the technological explosion.

What medium was primed for the technological explosion on Earth since the industrial revolution? I mean, I reckon we could point to an array of things that have seemed as though they would be a limit, but thus-far we've always found ways past that (see: peak oil). I'm not trying to indicate I think our trends _will_ go on forever, just that it seems possible they could.

Re: Beyond “Fermi’s Paradox” XVI: What Is the “Dark Forest” Hypothesis?

#213

Post by sangnoir »

Archelaos wrote: post #22

What makes the dark forest hypothesis not so conving to me is that it has the presupposition that it is indeed possible to hide. An advanced civilization close to us that is surveying the sky for signs of life would have very likely identified earth as a very promissing candidate due to the presence of methane and oxygen in its atmosphere at the same time. So our star system would have long been under surveillance, b…

> An advanced civilization close to us that is surveying the sky for signs of life would have very likely identified earth as a very promissing candidate due to the presence of methane and oxygen in its atmosphere at the same time.

Signs of carbon-based life - who is to say all forms of life are carbon-based? The universe is vast, what are the odds of aliens being in our vicinity and time (light cone) stumbling upon our galaxy or star?

Re: Beyond “Fermi’s Paradox” XVI: What Is the “Dark Forest” Hypothesis?

#214

Post by cogman10 »

yreg wrote: post #165
cogman10 wrote: post #159

Earlier quoted context omitted.

Yup, to me it implies a darker problem, that FLT is something that can't be surpassed. All civs might advance to that understanding and decide to maybe just occupy nearby solar systems and nothing more. We may not talk to them simply because it's both incredibly expensive and will yield nothing more than "Yup, we're stuck here, so are you".

Why wouldn't they send out autonomous research/exploration vessels? At a sufficient tech stage it's trivial.

Sure, they could, but imagine they are 10,000 light years away. Such a craft would need to travel for a long time before it could communicate back it's findings.

Re: Beyond “Fermi’s Paradox” XVI: What Is the “Dark Forest” Hypothesis?

#215

Post by jerf »

DonaldPShimoda wrote: post #193
jerf wrote: post #54

Earlier quoted context omitted.

I agree with your logic but would add one more thing to it: There is no compelling reason to wait until a planet conclusively proves it has intelligence on it to nuke it into oblivion with a kinetic kill projectile. You don't really know how long it will take for an intelligent species that could compete with you to arise. Humans have moved pretty quickly on cosmological scales, there's no particular reason to believ…

(Major spoilers for The Expanse below.) > There is no compelling reason to wait until a planet conclusively proves it has intelligence on it to nuke it into oblivion with a kinetic kill projectile. Or send a technologically engineered molecule that can hijack single-cellular life to help establish your needed technology in the target solar system.

That's a variant of what I discuss in another reply, but well underscores my point of just how easy this is if you happen to get there anywhere in the 2.0-2.4 billion window Earth has had prior to intelligence. If you colonize the system in any manner, be it biological, technological, whatever, for Dark Forest purposes that's equivalent to destruction; there is no longer a threat of natural competing life.

You've got two major approaches: Fling a kinetic kill projectile, or if you have the tech to get "something" into the target system at roughly orbital velocities, send some machines to do the job with local resources.

None of these things appear to have happened in Earth's past. Ironically, trying to spin yarns in which they did anyhow still end up countering the Dark Forest hypothesis, because all such attempts must either include significant probabilities of failure of the attempts or the possibility that the life out there is benevolent (to some degree, at least sufficient to avoid simply wiping us out, which on this scale is "benevolence" despite whatever else they may be doing) which itself would imply the forest isn't that dark.

Re: Beyond “Fermi’s Paradox” XVI: What Is the “Dark Forest” Hypothesis?

#216

Post by AnIdiotOnTheNet »

ping_pong wrote: post #211
AnIdiotOnTheNet wrote: post #45

Earlier quoted context omitted.

1) I think you're underestimating the difficulty of accelerating any massive object to relativistic speeds, 2) doing so with enough accuracy to hit a relatively small moving target many light-years away is not exactly trivial, 3) a civilization with the capability to accelerate a massive object to relativistic speeds is probably also capable of building self-sufficient artificial habitats around its star, which is a…

You're definitely not thinking creatively enough. You don't need to hit the planet directly with anything, all you need to do is destabilize the orbit of all the planets or even just the Earth itself. You could send a gravity wave for example, that would cause the Earth's near circular orbit to shift to a very eliptical orbit. The vast change in temperatures would kill all life on the planet, and then you could come…

If you have the capability of engineering such a gravity wave then Earth's resources aren't worth your time.

Re: Beyond “Fermi’s Paradox” XVI: What Is the “Dark Forest” Hypothesis?

#217

Post by 6510 »

miltondts wrote: post #126
aetherson wrote: post #85

Earlier quoted context omitted.

Short lived on those timescales, yes. But not necessarily short lived in terms of our perspective. If we imagine that in the last 5 billion years, there have been a good solid 10,000 post-industrial civilizations, and each of those civilizations has lasted 10,000 years (in the post-industrial stage where they're detectable), then that implies that of the last 5,000,000,000 years, 100,000,000 of them have been host to…

> if you've colonized say 20 stars, what disaster could possibly end your civilization? Unfortunately, war with another civilization.

Ours always rot from the inside out.

Re: Beyond “Fermi’s Paradox” XVI: What Is the “Dark Forest” Hypothesis?

#218

Post by tshaddox »

riffraff wrote: post #107
chadwittman wrote: post #69

Earlier quoted context omitted.

Read more about the Great Filter, it's probable it's ahead of us.

is it _probable_? AFA we know we've been insanely lucky up to this point (as earthling life we went past multiple mass extinctions, we got multi-cellular life, multiple brains iterations, a society which still didn't wipe itself out etc) What makes it more likely for the filter to be ahead of us rather than behind us?

Is it more likely that I’m immortal or that I simply have thus far avoided things that would have killed me?

Re: Beyond “Fermi’s Paradox” XVI: What Is the “Dark Forest” Hypothesis?

#219

Post by kadoban »

Supermancho wrote: post #207
tjalfi wrote: post #201

Earlier quoted context omitted.

> Maybe war between two spacefaring civilizations is too "easy". eg something like: throwing asteroids at ~the speed of light is necessarily a cheap thing to do once you're at that level, and everyone just dies. The Killing Star [0] and Flying to Valhalla by Charles Pellegrino are based around the idea that it's natural for a species to annihilate all other sentient species. The characters define three rules that an…

Given the relative emptiness of observed space, im not convinced that a civilization A would try to annihilate all life but would maybe war with others in their light cone who threaten civA goals/expansion. If you can traverse interstellar space you can probably make home most anywhere further reducing the amount of potential conflict.

How likely does it seem that if you can traverse interstellar space, your civilization splinters over time and your potential for internal conflict just grows without bound?

Re: Beyond “Fermi’s Paradox” XVI: What Is the “Dark Forest” Hypothesis?

#220

Post by not_jd_salinger »

myrmidon wrote: post #190
not_jd_salinger wrote: post #124

Earlier quoted context omitted.

> the fact that humans beings are doing better than they've ever done in our history by almost every imaginable metric. That's because we have had ready access to insanely abundant high-energy density source of energy. The non-fossil fuel supported carrying capacity of the planet for humans is estimated to be somewhere around 1 billion people. When the fuel runs out (if we don't cook ourselves first), that will colla…

What is your source for the 1 billion estimate? Because that seems completely, non-credibly *low* to me. I also strongly believe that we could cover all our energy needs with renewable sources within a few decades if we really wanted to (even assuming no significant advances in tech), and this seems mostly non-disputed to me (because that is literally what nation-states are currently planning/doing). > Is there even…

1 billion is a rough estimate based populations prior to the massive boom in the industrial revolution that saw massive changes in the way agriculture is done. It could easily be 2 billion or so, but definitely not 7.8 billion. You can see the population history here[0.]

To see the powerful impact of fossil fuels on carrying capacity you'll notice there's an important inflection point around 1920-1930. This is because of the advent of the Haber process[1] which allows us to use fossil fuels to create nitrogen based fertilizers.

Lest you doubt the impact of the Haber process just look at trends in corn yield per acre since then [2]. It's truly remarkable. Additional gains there are from other industrialized, fossil fuel driven agricultural process.

The Haber process requires hydrocarbons. In the wikipedia article you can see that it consumes 3-5% of the worlds natural gas production and 1-2% of the global energy supply.

We have completely disrupted the natural nitrogen cycle [4] and so would be unable to produce anywhere near as much food without fossil fuels. Because we have disrupted this cycle it's not even obvious that we could go back to a world of pre-fossil fuel agriculture.

So those are just some bit of information about my claims but let's take a look at yours:

> we could cover all our energy needs with renewable sources within a few decades if we really wanted to... this seems mostly non-disputed to me

This is wildly disputed, and I don't know anyone who credibly believes this without invoking "magic" future technology.

For starters we haven't replaced fossil fuels with "renewables" at all so far. We've just used them to supplement our energy needs. You can see here [4] that global fossil fuel consumption has continued to rise.

Then it is important to separate electricity from the more general subject of energy. Currently only 20% of global energy usage is electricity generation [5]. So even if you replaced the entire grid with renewables over night you would still be missing the vast majority of energy demands.

We currently have no viable pathway for renewable energy in transportation. Alice Friedman has more notes on this than I could ever fit in a comment [6]. Transportation inherently requires high energy density fuels, and outside of passenger vehicles, battery technology does not have the density required for industrial shipping.

It worth looking at our national energy flows to get a good sense of just how little of the energy we use comes from renewables [7].

But even if we look just at the electrical grid, in the US, we have some very obvious problems with "all" our needs. As you probably know, wind and solar are intermittent power sources that requires fossil fuel powered "peaker" plants to provide energy in down times.

This had two problems. One you need energy storage technology that we do not currently have (you cannot use grid scale lithium batters, pumped hydro has geological constraints, molten salts only work with concentrated solar, compressed air requires decommissioned oil field, etc).

The other problem is that even if you had perfect storage you need to now more than double the total energy production so you can fill those batteries.

The should be enough sources for you to get started, but I have feeling I'll still get down votes and "hand wavy" explanations of how it will all work out.

0. https://en.wikipedia.org/wiki/World_population#/media/File:W...

1. https://en.wikipedia.org/wiki/Haber_process

2. https://www.agry.purdue.edu/ext/corn/news/timeless/YieldTren...

3. https://en.wikipedia.org/wiki/Human_impact_on_the_nitrogen_c...

4. https://ourworldindata.org/grapher/global-energy-substitutio...

5. https://www.iea.org/reports/world-energy-outlook-2019/electr...

6. https://www.resilience.org/resilience-author/alice-friedeman...

7. https://flowcharts.llnl.gov/content/assets/images/charts/Ene...

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