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The Fermi paradox revisited: Technosignatures and the contact era

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Re: The Fermi paradox revisited: Technosignatures and the contact era

#51

Post by seanw444 »

drowsspa wrote: post #42
seanw444 wrote: post #27

Earlier quoted context omitted.

What's hard to comprehend is how there could be a possible way to preserve our consciousness through a hibernation state. Like, our cells might not die, and we might be technically revived, but we'd still be brain-dead. And if we figure it out, does the original "experiencer of consciousness" in that body return to life? Or is it a new consciousness, with the same memories, but the original person who went to sleep w…

That sounds like a non-issue. Our conscience already "pauses" when we go to sleep or get hit in the head, we already have people being resuscitated...

What if consciousness is something that can only be revived, with the revival of the body, a short period of time after the body "shuts down"? Like its own non-physical life form, for lack of better description.

We focus on the preservation of the body when talking about this stuff. But maybe the pattern of "waking up from normal sleep" doesn't hold true over such a time span?

Of course there's no scientific rebuttal for this fairly unscientific question, yet, but it's interesting to think about.

Re: The Fermi paradox revisited: Technosignatures and the contact era

#52

Post by maerF0x0 »

PaulHoule wrote: post #29
cannonpr wrote: post #11

Earlier quoted context omitted.

Because I suspect that under focused analysis the signal won’t quite look like cosmic radiation background. Now I also haven’t done the analysis, but information, and entropy are funny things. Will they get to watch a human TV show ? Hell no. Would it look “random” versus showing that it once contained some structured information ? I think that’s a very open question. There are probably more serious papers that deal…

An old NTSC video signal has a clear periodic structure. Simply counting lines is going to reveal a lot about the structure and if anyone gets the idea of plotting lines they will figure out how to decode it. An efficient digital signal is going to maximize the use of bandwidth if it looks like white noise. That said, a signal like that needs a carefully calibrated receiver, so part of the signal in time-frequency sp…

Makes me wonder if alien life will actually not find our messages simply because we're using such "ancient" techniques. Perhaps they invented a TV like object and used a NTSC like signal, but like 100k years ago and no one in their race knows to look for our old signals. Maybe our comms look like hieroglyphics to them ?

Re: The Fermi paradox revisited: Technosignatures and the contact era

#53

Post by bnralt »

tsimionescu wrote: post #31
bnralt wrote: post #15

Earlier quoted context omitted.

I've been wondering what the advantage of von Neumann probes are. Once you have the ability to autonomously construct probes, it seems like it would be easier and faster to mass produce them in one solar system and send them directly to their destinations. For instance, with a von Neumann probe you have to have probes with additional mass for self-replication, have it accelerate halfway to point A, decelerate halfway…

The point is that solar systems have tiny amounts of resources when compared against the idea of colonizing an entire galaxy, whereas the concept of a von Neumann probe swarm would have resources proportional to the task. Now, whether that is actually possible in any serious sense is very much in doubt.

There are ~2 x 10^9 stars in the solar system. The mass of earth is 6 x 10^24 kilos, with about 1/3 of that being iron. So even if we're just using the mass of a single celestial object the size of the earth, and only looking at iron alone, that'd be 1,000,000,000,000,000 kilos of iron you could use per star (for reference, this would be the equivalent of ~300 million fully fueled Saturn V's per star). It seems like a single solar system would have enough resources.

Re: The Fermi paradox revisited: Technosignatures and the contact era

#54

Post by izzydata »

douglaswlance wrote: post #13

If we assume alien life in the universe is predatory and seeks to consume other life forms, and since the universe allows detection from other species over infinite distances and time scales, we would expect life in the universe to either be totally undetectable or else be consumed by life that is totally undetectable.

If you are talking about a dark forest then it is more opf the idea that any other sufficiently advanced civilization would simply destroy you as soon as you are known to them rather than attempting to consume any potential resources you have as that isn't economical. The most economical thing could be as simple as sending a small object at light speed through your sun to cause a supernova.

This eliminates you as a potential threat and you have no chance to use other limited resources outside of that system.

Re: The Fermi paradox revisited: Technosignatures and the contact era

#55

Post by tsimionescu »

bnralt wrote: post #53
tsimionescu wrote: post #31

Earlier quoted context omitted.

The point is that solar systems have tiny amounts of resources when compared against the idea of colonizing an entire galaxy, whereas the concept of a von Neumann probe swarm would have resources proportional to the task. Now, whether that is actually possible in any serious sense is very much in doubt.

There are ~2 x 10^9 stars in the solar system. The mass of earth is 6 x 10^24 kilos, with about 1/3 of that being iron. So even if we're just using the mass of a single celestial object the size of the earth, and only looking at iron alone, that'd be 1,000,000,000,000,000 kilos of iron you could use per star (for reference, this would be the equivalent of ~300 million fully fueled Saturn V's per star). It seems like…

I am quite certain that using all of the iron in a single planet's core is well beyond the difficulty of building a self-replicating probe (which itself is well beyond our technical capabilities).

Not to mention, such probes are unlikely to be build able from a single metal, and some metals used for advanced electronics are significantly rarer than iron.

Re: The Fermi paradox revisited: Technosignatures and the contact era

#56

Post by YurgenJurgensen »

pharke wrote: post #38
api wrote: post #12

Earlier quoted context omitted.

If something visits us from another star system it's also likely to be an AI. Hibernation for thousands of years to travel between stars would be almost trivial for machine intelligence. Just turn yourself off. It'd be easy to tie this directly to solar power. Have an array of solar panels that powers you near a star and in interstellar space you just naturally go to sleep. When you approach the next star system the…

If we're talking about galactic distances and timescales I don't see why we couldn't safely assume enough technological advancement for either aliens or humans to modify their own biology to the point where centuries would be a small fraction of your total lifespan. I think the bigger question is why any significant number of people would travel to more than a few star systems if you had to do it slowly. If the syste…

If the Internet has told us anything, it's that as soon as the production of a self-replicating probe becomes accessible to a hobbyist, some people will do it even if there's no benefit to them. And it only takes one. The far future human colonists won't be landing on unspoilt wilderness; they'll be reclaiming systems from some 25th century script kiddy.

Re: The Fermi paradox revisited: Technosignatures and the contact era

#57

Post by izzydata »

cartercwchen wrote: post #24

I prefer the Dark Forest interpretation of the Fermi Paradox: https://en.wikipedia.org/wiki/Dark_forest_hypothesis

I thoroughly enjoyed Cixin Liu's Three Body series. Even if wildly unlikely I find the idea kind of comforting to existential dread despite it being possibly the worst fate for humanity.

Re: The Fermi paradox revisited: Technosignatures and the contact era

#58

Post by bnralt »

Hizonner wrote: post #45
bnralt wrote: post #15

Earlier quoted context omitted.

I've been wondering what the advantage of von Neumann probes are. Once you have the ability to autonomously construct probes, it seems like it would be easier and faster to mass produce them in one solar system and send them directly to their destinations. For instance, with a von Neumann probe you have to have probes with additional mass for self-replication, have it accelerate halfway to point A, decelerate halfway…

To send you back any information, your probe has to either send back something physical or use the electromagnetic spectrum. If you send a probe with no manufacturing capacity, then it either has to carry all the fuel, shielding, and redundancy for both directions of the trip, or carry a very large radio and its much larger power source. That's gonna be really, really heavy. Probably heavier than the manufacturing ma…

Like you said, if you want it to do "something interesting," like building a colony, we're not talking about probes anymore. But even then, it seems like mass producing the would be faster.

Consider - you're clearly going to be getting somewhere faster if you accelerate for 50,000 lightyears and decelerate for 50,000 than if you accelerate for 5, decelerate for 5, build a probe, accelerate for 5, decelerate for 5, build a probe, etc., 10,000 times. In the end you're going to be covering less distance if you go directly (because you're not zig-zagging from star to star), you're going to be reaching a higher maximum velocity (you're going to be accelerating for a longer length of time), and you won't have to wait to manufacture probes along the way.

Re: The Fermi paradox revisited: Technosignatures and the contact era

#59

Post by AnIdiotOnTheNet »

cartercwchen wrote: post #24

I prefer the Dark Forest interpretation of the Fermi Paradox: https://en.wikipedia.org/wiki/Dark_forest_hypothesis

You prefer to live in a universe where this is true, or just think it is the most likely explanation?

Because frankly you should seek help if it is the former.

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