4 ms·

Why, though? I hear this argument a lot, but never ever is it backed up by actual facts aside from assumptions (i.e. that technological civilisation build Von N

by qayxc 3y ago

Why, though? I hear this argument a lot, but never ever is it backed up by actual facts aside from assumptions (i.e. that technological civilisation build Von Neumann probes in the first place). So first question: why even Von Neumann probes? What would be the purpose of a self-replicating spacecraft? If it's science, then there's no reason to assume we would even be able to detect it. If it's some kind of colonisation effort, it only requires more assumptions. The basic assumption that the Fermi "Paradox" (I refuse to see it as a paradox) requires, is that technological civilisations remain unchanged over geologic time spans. That's a bold assumption, judging from our sample size of 1. Another assumption is that such civilisations grow exponentially for a practically unlimited amount of time (yeah, yeah, millions of years isn't exactly "unlimited", but on a human time scale it kind of is). Given the vast distances in both time and space, it's much more reasonable to acknowledge that technological civilisations are simply too far apart (in both time and space) to make contact in most cases. A thriving local interstellar civilisation on the other side of the Milky Way within the Zone of Avoidance would be virtually undetectable by us, for example.

brucethemoose2 3y ago
> that technological civilisations remain unchanged over geologic time spans Actually I think the opposite assumption, that civilization radically changes over time, is an argument for it. Future humanity is not people on (sublight) space boats touring the stars like Star Trek, its seemingly some kind of unfathomable transcendent intelligence. Maybe its not even recognized as "civilization" by our standards. And why would such an intelligence not explore its environment? What's the likelihood, if there are many such intelligences, that essentially all of these intelligences choose to remain static, stagnant and stealthy instead of making their presence known within their light horizon?
- qayxc 3y ago
  Well, there are a couple of problems with that. The god-like alien hypothesis is basically useless, as they would have no interest in us and would be undetectable anyway. The exploring civilisation falls into a similar category: if they are super advanced, they wouldn't be seen unless they want to. So no data point to be had there either. If they're just advanced enough to cross the vastness of interstellar space, they'd take hundreds or thousands of years to get around, so very little chance for them to randomly bump into us at this specific point in time. "Making your presence known" is also on shaky grounds, since it only takes one. By that I mean it only takes one locust-like civilisation that matches the "Grabby Aliens"-hypothesis to conquer the known universe within just a few billion years. This would imply, that it'd be highly likely that we ourselves would be part of- or descended from this super-civilisation. Again, the facts don't support that. OTOH, it also only takes one civilisation that wants to prevent such scenario. They don't even have to be around anymore. All it takes is seeding the universe with self-replicating "sentinels" that simply sit dormant around M-, K-, and G-type stars and watch. Once they detect a space-faring civilisation popping up, they'd being their assessment. If the AI suspects a "Grabby-Aliens"-scenario, it's time for Exterminatus or some other, more subtle means of preventing the scenario from materialising. So subtle in fact, that the affected civilisation might not even be aware of it. In fact, it could happen to us right now and we'd be none the wiser - ever wondered why it haven't made it back to the Moon in over 50 years ;) The fun part about this hypothesis is that it's just another scenario that we wouldn't be able to detect or rule out: GRBs happen all the time, good thing Earth hasn't been in the way of a nearby one... Or imagine another Carrington Event, only 50x stronger, blasting us back into the stone-age - just another otherwise oddly calm G-type star having a little hiccup; nothing unusual our extra-terrestrial neighbours would think... Basically the number of scenarios that would match our observations so far while still allowing for a universe teeming with technological civilisations, outnumbers any hypothesis that would truly present a "paradox" IMO. (just an opinion, not a fact, I could be very wrong on this)
ianai 3y ago
There doesn't need to be a why. With the time scales involved one successful Von Neumann probe civilization would quickly (at time scales of the universe) take over everything. That we don’t seem to see that is suggestive-either there’s no one else or there's a very strong, effective galactic or universal ban on VN probes. This somewhat suggests or relies on humans not being uniquely territorial and resource hungry. Kind of like the saying that if you see one cockroach you have many, many cockroaches.
- qayxc 3y ago
  Why doesn't there need to be a why? Outside of art (and even there I'm not sure), there's always a reason - especially if we are talking about an advanced civilisation. There's also no reason to believe this hasn't happened: 1) Galaxies far away are also far back in time - they could all be Dyson-sphered by now and we would be able to know for millions or billions years. 2) This also might have happened elsewhere - we have no means of detecting what's going on in nearby galaxy clusters, or even within our own Milky Way really. 3) In this line of thinking, alien civilisations are always a walking oxymoron or paradox themselves: so they are super-advanced, yet have to be detectable, and they think like us but also don't, because they know about the consequences but don't care about them. They also act without reason but at the same time with purpose. And they are superlong lived (or their machines are) yet feel the need to breed at insane levels to settle entire galaxies because of... of the resources they actually don't need if they wouldn't expand like crazy? - but wait, you said there is no reason - ah my head's spinning :)

by qayxc 3y ago

brucethemoose2 3y ago

> that technological civilisations remain unchanged over geologic time spans Actually I think the opposite assumption, that civilization radically changes over time, is an argument for it. Future humanity is not people on (sublight) space boats touring the stars like Star Trek, its seemingly some kind of unfathomable transcendent intelligence. Maybe its not even recognized as "civilization" by our standards. And why would such an intelligence not explore its environment? What's the likelihood, if there are many such intelligences, that essentially all of these intelligences choose to remain static, stagnant and stealthy instead of making their presence known within their light horizon?

qayxc 3y ago
Well, there are a couple of problems with that. The god-like alien hypothesis is basically useless, as they would have no interest in us and would be undetectable anyway. The exploring civilisation falls into a similar category: if they are super advanced, they wouldn't be seen unless they want to. So no data point to be had there either. If they're just advanced enough to cross the vastness of interstellar space, they'd take hundreds or thousands of years to get around, so very little chance for them to randomly bump into us at this specific point in time. "Making your presence known" is also on shaky grounds, since it only takes one. By that I mean it only takes one locust-like civilisation that matches the "Grabby Aliens"-hypothesis to conquer the known universe within just a few billion years. This would imply, that it'd be highly likely that we ourselves would be part of- or descended from this super-civilisation. Again, the facts don't support that. OTOH, it also only takes one civilisation that wants to prevent such scenario. They don't even have to be around anymore. All it takes is seeding the universe with self-replicating "sentinels" that simply sit dormant around M-, K-, and G-type stars and watch. Once they detect a space-faring civilisation popping up, they'd being their assessment. If the AI suspects a "Grabby-Aliens"-scenario, it's time for Exterminatus or some other, more subtle means of preventing the scenario from materialising. So subtle in fact, that the affected civilisation might not even be aware of it. In fact, it could happen to us right now and we'd be none the wiser - ever wondered why it haven't made it back to the Moon in over 50 years ;) The fun part about this hypothesis is that it's just another scenario that we wouldn't be able to detect or rule out: GRBs happen all the time, good thing Earth hasn't been in the way of a nearby one... Or imagine another Carrington Event, only 50x stronger, blasting us back into the stone-age - just another otherwise oddly calm G-type star having a little hiccup; nothing unusual our extra-terrestrial neighbours would think... Basically the number of scenarios that would match our observations so far while still allowing for a universe teeming with technological civilisations, outnumbers any hypothesis that would truly present a "paradox" IMO. (just an opinion, not a fact, I could be very wrong on this)

ianai 3y ago

There doesn't need to be a why. With the time scales involved one successful Von Neumann probe civilization would quickly (at time scales of the universe) take over everything. That we don’t seem to see that is suggestive-either there’s no one else or there's a very strong, effective galactic or universal ban on VN probes. This somewhat suggests or relies on humans not being uniquely territorial and resource hungry. Kind of like the saying that if you see one cockroach you have many, many cockroaches.

qayxc 3y ago
Why doesn't there need to be a why? Outside of art (and even there I'm not sure), there's always a reason - especially if we are talking about an advanced civilisation. There's also no reason to believe this hasn't happened: 1) Galaxies far away are also far back in time - they could all be Dyson-sphered by now and we would be able to know for millions or billions years. 2) This also might have happened elsewhere - we have no means of detecting what's going on in nearby galaxy clusters, or even within our own Milky Way really. 3) In this line of thinking, alien civilisations are always a walking oxymoron or paradox themselves: so they are super-advanced, yet have to be detectable, and they think like us but also don't, because they know about the consequences but don't care about them. They also act without reason but at the same time with purpose. And they are superlong lived (or their machines are) yet feel the need to breed at insane levels to settle entire galaxies because of... of the resources they actually don't need if they wouldn't expand like crazy? - but wait, you said there is no reason - ah my head's spinning :)