Some thoughts on the Fermi paradox

[rotting bones]

That doesn't answer the question. What does this allow you to do that the two envelopes can't?

The contents of the envelopes are determined by prior physical causes. The states of the particles are a heavenly miracle.

PS. The good news that quantum computer science wants to give the financial world is that we can now create passwords that are perfectly secure. Of course, those perfectly secure passwords need to be stored in this corrupt, dusty world of ours.

[zompist]

And how else are species going to communicate other than by electromagnetic radiation (light, radio) or vibrations induced in the surrounding medium (sound, tremors)? Once you know the signal, it's either ordered or not. If it's ordered, it's generated by life or not.

It's a good point that electromagnetic fields are really good for communication! But, as alternatives:

-- send a spaceship
-- hurl a rock (or any other piece of matter)
-- lay out some really long wires *
-- use gravity waves
-- send a stream of raw protons /neutrons
-- send neutrinos (they are detectable, but don't interact electrically)
-- wormholes ?
-- something something dark matter / dark energy

* This probably counts as a really bad idea, but sometimes those make good sf. After all, you've already given us a reason for doing it: so messages can't be detected as radiation. Wolfram Alpha tells me that a wire 1 mm wide and 4 light years long has a volume of 30 km³, which is easily doable.

(An ordinary wire can't carry a current that far, but some form of boosters could be strung along the wire...)

[zompist]

That doesn't answer the question. What does this allow you to do that the two envelopes can't?

The contents of the envelopes are determined by prior physical causes. The states of the particles are a heavenly miracle.

PS. The good news that quantum computer science wants to give the financial world is that we can now create passwords that are perfectly secure. Of course, those perfectly secure passwords need to be stored in this corrupt, dusty world of ours.

You're still not answering the question.

"Security" is at least a guess at an answer. But now we're talking operations. You have no proof that my random dice roll is compromised, and you have no proof that your quantum lab has no spies.

Sometimes people get so enamored of high tech solutions that they forget low tech exists. The classic example is the American space program, which spent huge sums to develop a pen that would work in a no-gravity environment. The Soviets used pencils.

[Ares Land]

For a civilization that spans a significant portion of a galaxy?

What's the point of broadcasting an SOS over interstellar distances? Unless FTL is possible, no one can rescue you in time.

If you need regular communication with ground control a focused signal is a better use of energy, I think.

What if new colonies are always popping up and you are broadcasting instructions, news and entertainment to them?

Within a solar system, they'd want, basically, an Internet connection, and that you'd get by focussed beams.

For interstellar colonies, why not? But these aren't likely to be always popping up. They're awfully expensive, and it'd take a very long time for them to be necessary... solar systems are big.

[rotting bones]

It's a good point that electromagnetic fields are really good for communication! But, as alternatives:

-- send a spaceship
-- hurl a rock (or any other piece of matter)
-- lay out some really long wires *
-- use gravity waves
-- send a stream of raw protons /neutrons
-- send neutrinos (they are detectable, but don't interact electrically)
-- wormholes ?
-- something something dark matter / dark energy

* This probably counts as a really bad idea, but sometimes those make good sf. After all, you've already given us a reason for doing it: so messages can't be detected as radiation. Wolfram Alpha tells me that a wire 1 mm wide and 4 light years long has a volume of 30 km³, which is easily doable.

(An ordinary wire can't carry a current that far, but some form of boosters could be strung along the wire...)

I brought up communication by matter myself later in my interminable monologue. I thought of projectiles, but decided it would be a bad idea.

You're still not answering the question.

"Security" is at least a guess at an answer. But now we're talking operations. You have no proof that my random dice roll is compromised, and you have no proof that your quantum lab has no spies.

Of course not. Fortunately, the financial world is easily impressed by hard math, and the math here is solid: https://en.wikipedia.org/wiki/Quantum_cryptography

[Ares Land]

You're still not answering the question.

"Security" is at least a guess at an answer. But now we're talking operations. You have no proof that my random dice roll is compromised, and you have no proof that your quantum lab has no spies.

Yep, that's it. You instantly know whether the message has been tampered with (well, once it leaves the lab of course!)
I've seen it mentioned in SF (though where was it? In Blindsight maybe?)

[rotting bones]

For a civilization that spans a significant portion of a galaxy?
What's the point of broadcasting an SOS over interstellar distances? Unless FTL is possible, no one can rescue you in time.

PS. To give an example for the first point, I'm imagining a biosphere failing very slowly, so it transmits an SOS. The decentralized network makes a decision to send materials to the habitat, etc.

[rotting bones]

Yep, that's it. You instantly know whether the message has been tampered with (well, once it leaves the lab of course!)
I've seen it mentioned in SF (though where was it? In Blindsight maybe?)

Well, you can know if it has been tampered with while it was being sent. But in practice, there is too much going on.

PS. I mean, the whole quantum system is embedded in classical reality. Why would you bother targeting the quantum part of the mechanism?

PPS. If you want to sell your own quantum snake oil to the financial world, this page gives an overview of how it works: https://en.wikipedia.org/wiki/Quantum_key_distribution

PPPS. You would be securing the network part of the system, the segment which is most vulnerable to attack. That part is not a lie.

[zompist]

PS. To give an example for the first point, I'm imagining a biosphere failing very slowly, so it transmits an SOS. The decentralized network makes a decision to send materials to the habitat, etc.

If I understand you, you're picture a civ sending out space habitats in all directions. Because the network doesn't know where they all are, habitats have to broadcast in all directions and the network has to listen in all directions.

My main point would be: space is big. Broadcasting in all directions is not going to be better than directed transmissions. If you send out 1000 space habitats, it's still cheaper to target each one. (Maybe you're thinking that they will change directions; but if they can send an SOS they can send a course correction.)

The other problem has already been pointed out: it's really hard to imagine circumstances where a rescue makes any sense. If they're 4 light years away maybe you can send something to help them (not exactly rescue them)... but if they're 4 ly away neither party is broadcasting. If they're 40 ly away, or 400... well, what kind of "emergency" is it that can be ameliorated 80 years later?

(As an sf writer, I'm sure you can come up with something. Weird scenarios make for good stories! But stories are about things going wrong, and if actual space agencies made the dumb design decisions people make in stories, their civs are unlikely to last very long.)

[rotting bones]

I am imagining that life in the Type II civilization is more or less like it is here. Just like the earth, every world is unstable and running out of time on the order of centuries. But unlike on earth, they request other habitats to send the materials they need and in turn send what the others need. Loosely speaking.

As for broadcasting, all life on earth that relies on communication uses it. If space is big, why is broadcasting in all directions, or at least towards the hemisphere that roughly faces civilization, not going to be better than focusing your beam in narrow angles towards where you last knew civilized life was supposed to exist? There might now be colonies that are much closer to you, but you don't know of their existence because they moved to those locations after your people set out to colonize this region, and there are light years separating the centers of civilization.

PS. Also, the older colonies could have moved or perished. Why risk it?

[zompist]

I am imagining that life in the Type II civilization is more or less like it is here. Just like the earth, every world is unstable and running out of time on the order of centuries. But unlike on earth, they request other habitats to send the materials they need and in turn send what the others need.

Then they're beyond help, as travel time is also measured in centuries.

If your aim is "at any cost, develop a sf scenario where a broadcast SOS message makes sense", I'm sure you can do it, and maybe it will be a cracking good yarn. What I'm not buying is that this is any guide to how interstellar civilizations can be expected to behave.

Oh, and just for fun... what sort of ubobtainium is a) so expensive that the biosphere is unable to get its own, b) so inexpensive that any node in the network can and should lob some at an SOS, and c) going to help in any way after 80 or 800 years?

[Ketsuban]

Sometimes people get so enamored of high tech solutions that they forget low tech exists. The classic example is the American space program, which spent huge sums to develop a pen that would work in a no-gravity environment. The Soviets used pencils.

Classic it may be, but it's untruthful. Paul Fisher developed the space pen out of his own pocket and then sold it to NASA. Pencils are a bad idea in oxygen-rich microgravity environments - the wood is flammable, the graphite floats around and conducts electricity to places you might not want it, and the records made with them are liable to get smudged and/or be hard to read, leading to copying errors. (The Soviets adopted Fisher's pen a couple of years after NASA.)

[zompist]

Sometimes people get so enamored of high tech solutions that they forget low tech exists. The classic example is the American space program, which spent huge sums to develop a pen that would work in a no-gravity environment. The Soviets used pencils.

Classic it may be, but it's untruthful. Paul Fisher developed the space pen out of his own pocket and then sold it to NASA. Pencils are a bad idea in oxygen-rich microgravity environments - the wood is flammable, the graphite floats around and conducts electricity to places you might not want it, and the records made with them are liable to get smudged and/or be hard to read, leading to copying errors. (The Soviets adopted Fisher's pen a couple of years after NASA.)

OK, thanks for the info. This is one of those things that get passed round the nerdosphere... it's a good reminder to verify them!

[rotting bones]

Then they're beyond help, as travel time is also measured in centuries.

If your aim is "at any cost, develop a sf scenario where a broadcast SOS message makes sense", I'm sure you can do it, and maybe it will be a cracking good yarn. What I'm not buying is that this is any guide to how interstellar civilizations can be expected to behave.

Well, I don't understand this weird obsession with directed messages. Nor do I see why they are more efficient, progressive or whatever when they obviously don't make sense for a galactic civilization that doesn't know who its neighbors are.

Oh, and just for fun... what sort of ubobtainium is a) so expensive that the biosphere is unable to get its own, b) so inexpensive that any node in the network can and should lob some at an SOS, and c) going to help in any way after 80 or 800 years?

It's about economies of scale. It's cheaper to make the same goods in large quantities.

[zompist]

Then they're beyond help, as travel time is also measured in centuries.

If your aim is "at any cost, develop a sf scenario where a broadcast SOS message makes sense", I'm sure you can do it, and maybe it will be a cracking good yarn. What I'm not buying is that this is any guide to how interstellar civilizations can be expected to behave.

Well, I don't understand this weird obsession with directed messages. Nor do I see why they are more efficient, progressive or whatever when they obviously don't make sense for a galactic civilization that doesn't know who its neighbors are.

I feel like I'm starting to repeat myself, so I'll let it go after this. This "weird obsession" is what our current global civilization is doing. It's more efficient to direct your energy rather than toss most of it into space. I don't really see why these things are hard to understand.

A "galactic civilization that doesn't know who its neighbors are" is possible, but also making it so that it depends for its survival on random SOSes is a couple weirdnesses too much for me.

[rotting bones]

I feel like I'm starting to repeat myself, so I'll let it go after this. This "weird obsession" is what our current global civilization is doing. It's more efficient to direct your energy rather than toss most of it into space. I don't really see why these things are hard to understand.

A "galactic civilization that doesn't know who its neighbors are" is possible, but also making it so that it depends for its survival on random SOSes is a couple weirdnesses too much for me.

What's weird about distributed resource allocation? It is standard technology: https://arxiv.org/abs/1409.2475 https://scholar.google.com/scholar?hl=e ... tion&btnG=

In these systems, nodes in the network send messages to their neighbors without having direct knowledge of their internal states. Nodes can even fail right in the heart of the network, but the algorithm is designed so that everything works out anyway in the long run.

I'm not assuming ignorance of neighboring habitats for no reason. They are separated by light years. Assuming FTL doesn't exist, I don't understand how they can possibly have direct knowledge of what's going on out there.

Directed messages are possible on earth because we have entered a relatively stable period, and we know the destinations of our messages. Imagine a medieval society. If a farmer leaves to visit the city, it is not inconceivable that he will never return, but they keep doing it anyway.

In that society, maps may not even exist. At each location, the farmer joins the throng heading to their common destination. My scenario is not even as bad as average pre-modernity. Which of my assumptions are fantastic?

[Moose-tache]

order is objective: https://en.wikipedia.org/wiki/Negentropy

This is not the same as saying "artificial production is obvious." For example, sonar pings nowadays are made to contain no repeated notes, because they don't want harmonics to obfuscate their readings. In entropy terms, these sonar pings are indistinguishable from random noise. People in this thread have suggested that even low-information signals like SOS calls should be recognizable as communication. That seems like a stretch to me.

[rotting bones]

That depends on the structure of the message. It needs to be recognized as artificial by the recipient. Whatever header marks it as such is likely to be highly ordered, since that is its one job. As for the contents, a record of goods produced and list of requirements would resemble a sequence of numbers when decompressed. Of course, the contents will almost certainly be somewhat compressed, and that will increase its entropy.

PS. Even if it's just an SOS message, it has to be such that the intended recipient can't mistake it for a natural radio emission. If they can't mistake it, then why can we?

[zompist]

Which of my assumptions are fantastic?

Well, since you ask:

1. That a spacefaring civilisation is expanding massively
2. That it's doing so without tracking its colonies
3. That they require ongoing shipments of material goods
4. That shipments are not coordinated, but are sent in response to randomly broadcast queries
5. That colonies are normally in a dire state and won't last centuries
6. That they place orders that can't be fulfilled for centuries

If there's a common thread, it's maybe that each of these points become unlikely on its own, and vanishingly unlikely all together, the more it costs to do travel and communications. And in an STL universe, that cost is very high.

If you wanted to make this work for a story or conworld, I think it'd work for a non-sentient species which nonetheless has spaceflight. (Perhaps they evolved from a sentient race and kept the tools without understanding them.) So they expand without planning because they are incapable of planning. They aren't too good at survival, so when they do find a successful niche they export goods widely and wildly. They'd be a sort of interstellar virus, possibly a pest to the sentient species (because if you try to eradicate a node, any nearby successful nodes mob you).

[rotting bones]

It won't seem that way to the people living there when cargo is constantly entering and leaving. I wish cargo were coming to earth that would render irrelevant any climate crises headed our way. I would be willing to work in order to manufacture whatever goods were wanted in return.

This faith is not so different from the one that keeps terrestrial civilization ticking. Tomorrow, everyone might betray me for no reason, but if that kept happening, then the consequences could be dire for everyone's standard of living.

PS. Of course, in this civilization, workers (probably) won't be sweating on factory floors. They will be controlling the machines that manufacture goods and mine asteroids, and perhaps performing manual maintenance work on their infrastructure once in a while.