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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?

#261

Post by krapp »

crowbahr wrote: post #239
edgyquant wrote: post #230

Earlier quoted context omitted.

relatively scarce, sure. There are millions of times more of all the resources Earth has between us and any civilization coming from light years away. By the time they needed Earths resources they’d have to have gobbled up large chunks of, if not the whole, Galaxy.

Right but the whole premise of the Fermi Paradox is that it doesn't take long (on a galactic scale) to gobble up the entire galaxy using STL transit if you're dealing with a constantly growing civilization. So either they'd - already have gotten here & already have destroyed the earth when we showed intelligence OR - already have gotten here & don't care about destroying intelligence.

>So either they'd - already have gotten here & already have destroyed the earth when we showed intelligence OR - already have gotten here & don't care about destroying intelligence.

Or... civilizations don't experience unbounded growth over millions of years across millions of light years to begin with.

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

#262

Post by pharke »

NiceWayToDoIT wrote: post #183
colinmhayes wrote: post #175

Earlier quoted context omitted.

If civilization as we know it ends but humanity survives it would be very difficult for future generations to reestablish because we've used up all the easy to access hydrocarbons. Without easy to reach coal there won't be another industrial revolution and humanity would be stuck for millions of years until the hydrocarbons reform.

That is some kind of Oil centric thinking that got us in this mess in the first place. Renewables and fusion can do the much better better job at any point. By the way coal will not form ever again, only reason why coal/oil formed is because bacteria has not learned how to decompose cellulose at the time. https://www.nationalgeographic.com/science/article/the-fanta...

I believe that theory is no longer valid. It was supposedly fungus that feeds on woody plants that resulted in a drop in lignin rich coal but that doesn't seem to quite work out. Coal is formed when there's a lot of organic matter that gets trapped in an oxygen poor environment and then buried and compressed over time. That process is certainly still happening though not at the same rate it has in the past. This article has some good details https://arstechnica.com/science/2016/01/why-was-most-of-the-...

There's still quite a lot of coal though.

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

#263

Post by AmericanChopper »

rnhmjoj wrote: post #29

> In other words, the finite nature of resources will ultimately pit one civilization against another as they all struggle to sustain their growth. I'm not sure this constraint is so strict to force a strong competition for survival, given how vast the universe is. It seems to me this projecting our earth-bound mentality of limited resources to a whole different scale, where it may not really apply.

According to this theory, the resource consumers in the universe are just as vast as the universe itself. At the end of the series the final resource constraint they deal with is running out of physical matter in the universe. Once the civilizations depicted in the book are done mastering survival in this universe, they all turn their attention to surviving the death of the universe. Stability simply moves the survival goalposts, and “we could probably last a few billion years” (or rephrased, “we will probably perish in a few billion years”) becomes the new existential crisis to solve.

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

#264

Post by pharke »

hnbad wrote: post #112
myrmidon wrote: post #73

Earlier quoted context omitted.

Do you think there is a "real" (>1% over the next century) risk for humanity to wipe itself out, or just that the hostile-alien risk is way beyond negligible in comparison? Because all current climate doom-erism notwithstanding-- humanity extinction seems impossible to achieve to me via climate change or nuclear war; rogue autonomous self-replicating systems might be a danger, but are too far beyound current tech to…

We don't need to go extinct. Our global economy is very fragile, relatively speaking and it's not at all clear we could sustain the economy necessary to perform space exploration if bad things happen. To avoid an extended argument about all the ways in which climate change will screw things up, let's focus on nuclear war: a nuclear war between, say, India and China would not only wipe out huge swaths of the human pop…

Those convoluted supply chains are a recent phenomena. Some international trade is necessary but large countries like the United States are capable of producing almost everything they require domestically. Trade is only preferable if you can import something for less money than you can manufacture it locally.

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

#265

Post by mikevin »

e40 wrote: post #234
aeturnum wrote: post #205

Earlier quoted context omitted.

I think people are alarmed, but solutions to these problems are enormously costly and largely fictional. The techniques we have for living in space (or transiting through it) would not sustain us if we lost earth. They are enormously costly[1], which is fine for what we are doing, but we need multiple orders-of-magnitude improvement to be practically interstellar. On balance, I think we could spend more, but I also t…

> I think people are alarmed I think your view is skewed. Every single person I've talked to about this as looked at me like they are bored. Of course, here on HN, I've found many like-minded people. That's great, but I think very few humans, especially humans in the power structures that run this planet, care about this issue.

I think that's a pretty healthy reaction, pretty much all of human history took place in an environment where investing time an energy in thinking/caring about "the big picture"/"distant future" would drastically lower your chances of survival. Even today there's still plenty of people who have to worry about having something to eat tomorrow.

We're slowly getting comfortable enough about our immediate situation, leaving room to start thinking on a bigger scale. But I think it takes actual effort to say: "ok brain, I understand our immediate situation is important but I think we've got that covered enough to allow us to start caring about the less immediate problems we might face"

I'm a glass half full guy so maybe it's naive but I think we're actually doing pretty well. Climate change sucks and we're pretty slow to respond but you wouldn't expect a hunter/gatherer to be able to see the importance of fighting it. Our situation is different but the brain isn't all that different when it comes to prioritizing things to spend time/energy on. Obesity is a good example of what happens when you combine ancient instincts with modern situations.

Same thing probably goes for racism. We're advanced enough to know better and responsible for our actions but we're dealing with a brain has evolved mostly during times where trusting other tribes and survival of the fittest were Incompatible. Xenophobia had some evolutionary benefit and now we have to deal with it's existence in a vastly different situation.

Like I said, people should know better and have to be held responsible for their actions and we should never be comfortable with the slow rate of change. Still I like to remind myself every now and then that its amazing how much progress has already been made changing things that evolution hasn't had time to value yet.

This turned out way longer than I expected but it's something I think about a lot. Hope you don't mind me using your comment to finally put some thoughts into words.

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

#266

Post by giantrobot »

nikhilgk wrote: post #203
giantrobot wrote: post #191

Earlier quoted context omitted.

Even broadcast emissions aren't detectable at long distances. If you parked an Arecibo-class telescope in orbit around Alpha Centauri the only signals you'd detect coming from Earth would be intentional directional transmissions from an Arecibo-class (or Goldstone class) radar. Our television and radio broadcasts aren't detectable by an Arecibo-class telescope out much past Jupiter let alone outside the solar system.…

> Even then out past a thousand light years even a multi-terawatt (EIRP) signal would be difficult to detect. Not necessarily. Gravitational lensing may enable directed communication at much lower power levels : https://storkpaulo.wordpress.com/2010/04/26/gravitational-le...

Leaving the serious engineering difficulties involved in a solar gravitational lensing system aside, such a system doesn't necessarily help in picking up just random omnidirectional broadcasts from an ETI.

Say we had an SGL telescope positioned such to image an Earth-sized planet we know is in orbit of Alpha Centauri A. For ease of math we'll say this Earth sized planet is at a distance such the solar constant is the same as Earth. So that's a total power received from the Sun of 1.74x10^17 watts and with the Earth's mean albedo of 0.3 about 5.22x10^16 watts being reflected off into space.

We can use our SGL to image the planet around Alpha Centauri because it's reflecting 52.2 petawatts of sunlight out into space. So it takes the power of a star reflecting off a disc with a cross sectional area of 1.26x10^8 square kilometers for a proposed SGL system to detect and image a planet.

The amount of power an omnidirectional antenna can possibly emit is somewhat less than 52 petawatts. Broadcast antennas output at most a few megawatts EIRP because there's no utility in blasting out hundreds of megawatts for terrestrial transmission. Such broadcasts just aren't going to be detectable even with gravitational lensing from our Centauran neighbors.

Nor are gravitational lenses terribly useful for beacons since you need the right geometry between the sender, star, and receiver to use the lens. You could use lensing to increase the EIRP of your transmission but only at a specific target. Nobody outside the focal plane of the lensing system is going to benefit from the lens.

SGLs are a neat idea and an interesting topic but I don't think they solve many SETI problems.

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

#267

Post by toufka »

0-_-0 wrote: post #163
snowwrestler wrote: post #48

To me the most likely back of the napkin answer to the Fermi paradox is that aliens are elsewhere in time. The Milky Way galaxy is about 100,000 light years across but about 13.5 billion years old. So it’s like 135,000x deeper in the time direction than the distance direction. We’re in the light cones of all the stars we can see, and as far as we know, we can’t get out of them. If a civilization ended even 100 years…

It's much easier to traverse 1 year in time then 1 light year in space though

Is it? I can move all sorts of distances, in different directions, at all sorts of rates. It's surely harder to go certain speeds than others, and in certain directions than others. But to move 1 year in time - I only have one speed and one direction to move.

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

#268

Post by tjalfi »

ping_pong wrote: post #209
evrydayhustling wrote: post #19

Earlier quoted context omitted.

As other commenters have said, we can't take our own viewpoint as an example of what kinds of civilizations survive because our technological age is so young. But IMO Dark Forest is bunk anyway, because it assumes that projecting power over interstellar distances is easier than defending yourself. That's not true within terrestrial history ... even though the arrival of colonists was massively disruptive to populatio…

> On Earth, successful civilizations have been capable of trade and cultural exchange in addition to force. Forget about what monstrosities we have done to other human civilizations throughout history. Instead, think about what we have done to animals. We have hunted many animals out of existence, or we have farmed them and made them basically the equivalent of the Matrix, sources of energy and food. We are trying to…

John Varley's Eight Worlds[0] series has an alien species called the Invaders. They invaded Earth to protect cetaceans from the effects of human civilization.

The Invaders divide sentient life into three tiers - species like themselves that evolve in gas giants, cetaceans, and vermin; we're in the third category.

[0] https://en.wikipedia.org/wiki/Eight_Worlds

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

#269

Post by AmericanChopper »

formerly_proven wrote: post #30

This paper discusses the "dark forest" idea and concludes that it is very unlikely to be true: https://arxiv.org/abs/1302.0606 MAD with Aliens? Interstellar deterrence and its implications

The “MAD with Aliens” portion of the book isn’t particularly relevant to the dark forest theory it postulates. The MAD in the book only applies to a conflict between earth and another nearby non-technologically-sophisticated alien spices, who are competing for earths resources in order to survive. The conflict is resolved by both us and them advancing beyond the need for earth, and becoming full dark forest participants.

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

#270

Post by mentalpiracy »

AnIdiotOnTheNet wrote: post #216
ping_pong wrote: post #211

Earlier quoted context omitted.

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.

Resources not the point here, the point is removing the possibility that our civ could ever be a risk to them
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