One argument against the presence of other technological civilizations in the Milky Way is that if they were here, they would already have colonized the galaxy. I don't find that argument compelling.
Consider ourselves! We count as a technological civilization, yet we are so very far from colonizing the galaxy. No man made spacecraft has made it farther into the surrounding universe than just outside the solar system, and that spacecraft, Voyager 1, is not heading for another star at all, let alone an exoplanet. Suppose it eventually landed on exoplanet after all, and miraculously avoided crashing on it. How would it go about colonizing it?
What would it take to colonize the galaxy? How much money would it take, and more importantly, what sort of resources would it take to build the sort of army of spacecraft that would be needed for the task? I realize that those spacecraft would probably mostly be unmanned, and that they would be intelligent enough to use resources on other planets to create replicas of themselves that could go on colonizing the galaxy. But really, seriously, it sounds so science fiction-y.
And just one more question. If we managed to build spacecraft that would be able to colonize the galaxy - and I just can't imagine how we would do it - then how would it benefit us to have spacecraft colonizing the far end of the Milky Way, if we ourselves were stuck on the Earth?
Ann
Why do we assume that an alien technological civilization would already have colonized the Milky Way?
Re: Why do we assume that an alien technological civilization would already have colonized the Milky Way?
I think the distinct lack of evidence for advanced civilizations suggests they occur rarely in the universe. It’s an interesting but (probably) unanswerable question because there are so many variables we have yet to quantify.
I’d start by asking a series of nested questions: how rare is life in the universe? If life is common, how often does it evolve to become complex? If complex life is common, how often does intelligence emerge? If intelligent life is common, how often does it form complex societies? And how many of these societies advance far enough to build radio transceivers?
More questions: what if life is common in the universe but most of it simple / single-celled? What if intelligent life is common but rarely moves past the intelligence of mammals or birds? What if early societies are common but rarely develop beyond hunter-gathering or agriculture?
The “dream scenario” would be interplanetary interaction between advanced societies. However, in order for this to happen you’d need two advanced societies in close proximity, both in space and time. Continuing with my initial line of questions, what are the odds that two nearby societies would reach “maturity” within the same epoch of time? A quick Google search returns a value for the age of homo sapiens at around 160,000 years. What percentage of that time has homo sapiens been listening to interstellar radio transmissions - compared to the time we’ve spent banging rocks against other rocks?
One thing I’ve considered is the idea that perhaps technology only develops from “unlikely survivors.” Whales and porpoises are roughly 10 million years old. They have larger brains than we do. They form complex social bonds/groups. However, they are so well adapted to their environment there would be no pressure to “try anything” to help their survival. They move easily and as fast as they need. They can use sound to communicate vast distances, echo-locate and even attack prey (see: dolphin sound pulses). Homo sapiens on the other hand - not particularly fast or strong, no big teeth or claws, no thick hides or blubber to stay warm. Perhaps need is what pushed us toward the eventual use of clothes, fire, rudimentary tools. From there agriculture, complex society, and (roughly) continuous technological advance. The point is that you could have complex intelligent life forming on other planets that never develop into technological societies. But then, could a species reach agrarian status and stay there for vast periods - never developing industry or what we would call modern technology? Once again, you’d never get a radio transmission, but you might detect indications of such a society in the planet’s atmosphere such as an overabundance of methane and O2.
Ann, you point out that we “count ours as a technological society.” I think a reasonable litmus test to signify “technological status” would be radio (perhaps more reasonable than "warp-capable" ala Star Trek). There could be many civilizations that never reach the point of radio and thus we’d never know about each other. For our part, we’ve only been transmitting and listening to radio for a little more than 100 years. Therefore, only societies that have developed within a tiny bubble around Sol could be aware of us (yet). If my initial assertion is accurate and advanced societies are in fact rare - and we assume societies are fairly evenly spread across the universe - the odds are infinitesimally small that a second radio-capable society would develop in our galaxy, let alone within close proximity (in both time and location) to our own.
My feeling is that either advanced societies are extremely rare and thus perpetually alone; or they are numerous but short-lived, galactically-speaking, and as such it is unlikely that any one society would detect another. It is reasonable to me that the only evidence we’ll ever detect indicating the existence of another civilization will be ancient, feeble radio transmissions of long-dead societies or a few photons in a spectrometer indicating traces of gasses that may or may not have been produced by a developing society blissfully unaware of radio.
I’d start by asking a series of nested questions: how rare is life in the universe? If life is common, how often does it evolve to become complex? If complex life is common, how often does intelligence emerge? If intelligent life is common, how often does it form complex societies? And how many of these societies advance far enough to build radio transceivers?
More questions: what if life is common in the universe but most of it simple / single-celled? What if intelligent life is common but rarely moves past the intelligence of mammals or birds? What if early societies are common but rarely develop beyond hunter-gathering or agriculture?
The “dream scenario” would be interplanetary interaction between advanced societies. However, in order for this to happen you’d need two advanced societies in close proximity, both in space and time. Continuing with my initial line of questions, what are the odds that two nearby societies would reach “maturity” within the same epoch of time? A quick Google search returns a value for the age of homo sapiens at around 160,000 years. What percentage of that time has homo sapiens been listening to interstellar radio transmissions - compared to the time we’ve spent banging rocks against other rocks?
One thing I’ve considered is the idea that perhaps technology only develops from “unlikely survivors.” Whales and porpoises are roughly 10 million years old. They have larger brains than we do. They form complex social bonds/groups. However, they are so well adapted to their environment there would be no pressure to “try anything” to help their survival. They move easily and as fast as they need. They can use sound to communicate vast distances, echo-locate and even attack prey (see: dolphin sound pulses). Homo sapiens on the other hand - not particularly fast or strong, no big teeth or claws, no thick hides or blubber to stay warm. Perhaps need is what pushed us toward the eventual use of clothes, fire, rudimentary tools. From there agriculture, complex society, and (roughly) continuous technological advance. The point is that you could have complex intelligent life forming on other planets that never develop into technological societies. But then, could a species reach agrarian status and stay there for vast periods - never developing industry or what we would call modern technology? Once again, you’d never get a radio transmission, but you might detect indications of such a society in the planet’s atmosphere such as an overabundance of methane and O2.
Ann, you point out that we “count ours as a technological society.” I think a reasonable litmus test to signify “technological status” would be radio (perhaps more reasonable than "warp-capable" ala Star Trek). There could be many civilizations that never reach the point of radio and thus we’d never know about each other. For our part, we’ve only been transmitting and listening to radio for a little more than 100 years. Therefore, only societies that have developed within a tiny bubble around Sol could be aware of us (yet). If my initial assertion is accurate and advanced societies are in fact rare - and we assume societies are fairly evenly spread across the universe - the odds are infinitesimally small that a second radio-capable society would develop in our galaxy, let alone within close proximity (in both time and location) to our own.
My feeling is that either advanced societies are extremely rare and thus perpetually alone; or they are numerous but short-lived, galactically-speaking, and as such it is unlikely that any one society would detect another. It is reasonable to me that the only evidence we’ll ever detect indicating the existence of another civilization will be ancient, feeble radio transmissions of long-dead societies or a few photons in a spectrometer indicating traces of gasses that may or may not have been produced by a developing society blissfully unaware of radio.
-
Chris Peterson
- Abominable Snowman
- Posts: 18612
- Joined: Wed Jan 31, 2007 11:13 pm
- Location: Guffey, Colorado, USA
- Contact:
Re: Why do we assume that an alien technological civilization would already have colonized the Milky Way?
It seems unlikely that any water-based life would develop technology. Just too difficult. But maybe the bigger issue is that technological intelligence in a biological life form is just so fragile. Perhaps technological biological animals are quickly replaced with "artificial" ones. We're not far from that capability ourselves.Orca wrote: ↑Sat Jul 27, 2024 6:40 pm I think the distinct lack of evidence for advanced civilizations suggests they occur rarely in the universe. It’s an interesting but (probably) unanswerable question because there are so many variables we have yet to quantify.
I’d start by asking a series of nested questions: how rare is life in the universe? If life is common, how often does it evolve to become complex? If complex life is common, how often does intelligence emerge? If intelligent life is common, how often does it form complex societies? And how many of these societies advance far enough to build radio transceivers?
More questions: what if life is common in the universe but most of it simple / single-celled? What if intelligent life is common but rarely moves past the intelligence of mammals or birds? What if early societies are common but rarely develop beyond hunter-gathering or agriculture?
The “dream scenario” would be interplanetary interaction between advanced societies. However, in order for this to happen you’d need two advanced societies in close proximity, both in space and time. Continuing with my initial line of questions, what are the odds that two nearby societies would reach “maturity” within the same epoch of time? A quick Google search returns a value for the age of homo sapiens at around 160,000 years. What percentage of that time has homo sapiens been listening to interstellar radio transmissions - compared to the time we’ve spent banging rocks against other rocks?
One thing I’ve considered is the idea that perhaps technology only develops from “unlikely survivors.” Whales and porpoises are roughly 10 million years old. They have larger brains than we do. They form complex social bonds/groups. However, they are so well adapted to their environment there would be no pressure to “try anything” to help their survival. They move easily and as fast as they need. They can use sound to communicate vast distances, echo-locate and even attack prey (see: dolphin sound pulses). Homo sapiens on the other hand - not particularly fast or strong, no big teeth or claws, no thick hides or blubber to stay warm. Perhaps need is what pushed us toward the eventual use of clothes, fire, rudimentary tools. From there agriculture, complex society, and (roughly) continuous technological advance. The point is that you could have complex intelligent life forming on other planets that never develop into technological societies. But then, could a species reach agrarian status and stay there for vast periods - never developing industry or what we would call modern technology? Once again, you’d never get a radio transmission, but you might detect indications of such a society in the planet’s atmosphere such as an overabundance of methane and O2.
Ann, you point out that we “count ours as a technological society.” I think a reasonable litmus test to signify “technological status” would be radio (perhaps more reasonable than "warp-capable" ala Star Trek). There could be many civilizations that never reach the point of radio and thus we’d never know about each other. For our part, we’ve only been transmitting and listening to radio for a little more than 100 years. Therefore, only societies that have developed within a tiny bubble around Sol could be aware of us (yet). If my initial assertion is accurate and advanced societies are in fact rare - and we assume societies are fairly evenly spread across the universe - the odds are infinitesimally small that a second radio-capable society would develop in our galaxy, let alone within close proximity (in both time and location) to our own.
My feeling is that either advanced societies are extremely rare and thus perpetually alone; or they are numerous but short-lived, galactically-speaking, and as such it is unlikely that any one society would detect another. It is reasonable to me that the only evidence we’ll ever detect indicating the existence of another civilization will be ancient, feeble radio transmissions of long-dead societies or a few photons in a spectrometer indicating traces of gasses that may or may not have been produced by a developing society blissfully unaware of radio.
Spreading across a galaxy is not hard. It can be done in a few million years, which should not be a problem for a stable "civilization". But what would be the motivation? It's not like these different "colonies" are going to interact significantly with each other, so no great galactic empire of some sort. Each one will be pretty isolated (or together with a fairly small handful of nearby systems). Academic interest? How many other stars do you need to visit before curiosity is satisfied? Population management? Why would non-biological beings with extremely long lifetimes necessarily have any imperative to breed?
Chris
*****************************************
Chris L Peterson
Cloudbait Observatory
https://www.cloudbait.com
*****************************************
Chris L Peterson
Cloudbait Observatory
https://www.cloudbait.com
Re: Why do we assume that an alien technological civilization would already have colonized the Milky Way?
I have been reading Cixin Liu's Three Body Problem trilogy over the past few years. Highly recommend!! Has anyone else here read it?Chris Peterson wrote: ↑Sat Jul 27, 2024 7:02 pm But maybe the bigger issue is that technological intelligence in a biological life form is just so fragile.
Here's an applicable excerpt from Death's End for this thread, hopefully with no spoilers:
"No avian society ever develops space travel because it's impossible to focus on calculus when you could be outside flying." -Randall Munroe
Re: Why do we assume that an alien technological civilization would already have colonized the Milky Way?
Thank you, Orca, for that extremely thoughtful input. Thanks to you too, Chris, for your answer to Orca. I agree with all of the points from both of you.Orca wrote: ↑Sat Jul 27, 2024 6:40 pm I think the distinct lack of evidence for advanced civilizations suggests they occur rarely in the universe. It’s an interesting but (probably) unanswerable question because there are so many variables we have yet to quantify.
I’d start by asking a series of nested questions: how rare is life in the universe? If life is common, how often does it evolve to become complex? If complex life is common, how often does intelligence emerge? If intelligent life is common, how often does it form complex societies? And how many of these societies advance far enough to build radio transceivers?
More questions: what if life is common in the universe but most of it simple / single-celled? What if intelligent life is common but rarely moves past the intelligence of mammals or birds? What if early societies are common but rarely develop beyond hunter-gathering or agriculture?
The “dream scenario” would be interplanetary interaction between advanced societies. However, in order for this to happen you’d need two advanced societies in close proximity, both in space and time. Continuing with my initial line of questions, what are the odds that two nearby societies would reach “maturity” within the same epoch of time? A quick Google search returns a value for the age of homo sapiens at around 160,000 years. What percentage of that time has homo sapiens been listening to interstellar radio transmissions - compared to the time we’ve spent banging rocks against other rocks?
One thing I’ve considered is the idea that perhaps technology only develops from “unlikely survivors.” Whales and porpoises are roughly 10 million years old. They have larger brains than we do. They form complex social bonds/groups. However, they are so well adapted to their environment there would be no pressure to “try anything” to help their survival. They move easily and as fast as they need. They can use sound to communicate vast distances, echo-locate and even attack prey (see: dolphin sound pulses). Homo sapiens on the other hand - not particularly fast or strong, no big teeth or claws, no thick hides or blubber to stay warm. Perhaps need is what pushed us toward the eventual use of clothes, fire, rudimentary tools. From there agriculture, complex society, and (roughly) continuous technological advance. The point is that you could have complex intelligent life forming on other planets that never develop into technological societies. But then, could a species reach agrarian status and stay there for vast periods - never developing industry or what we would call modern technology? Once again, you’d never get a radio transmission, but you might detect indications of such a society in the planet’s atmosphere such as an overabundance of methane and O2.
Ann, you point out that we “count ours as a technological society.” I think a reasonable litmus test to signify “technological status” would be radio (perhaps more reasonable than "warp-capable" ala Star Trek). There could be many civilizations that never reach the point of radio and thus we’d never know about each other. For our part, we’ve only been transmitting and listening to radio for a little more than 100 years. Therefore, only societies that have developed within a tiny bubble around Sol could be aware of us (yet). If my initial assertion is accurate and advanced societies are in fact rare - and we assume societies are fairly evenly spread across the universe - the odds are infinitesimally small that a second radio-capable society would develop in our galaxy, let alone within close proximity (in both time and location) to our own.
My feeling is that either advanced societies are extremely rare and thus perpetually alone; or they are numerous but short-lived, galactically-speaking, and as such it is unlikely that any one society would detect another. It is reasonable to me that the only evidence we’ll ever detect indicating the existence of another civilization will be ancient, feeble radio transmissions of long-dead societies or a few photons in a spectrometer indicating traces of gasses that may or may not have been produced by a developing society blissfully unaware of radio.
What I can't figure out is why an army of robots would want to colonize the Milky Way. What would be the point?
Do Androids Dream of Electric Sheep, asked Philip K. Dick. For myself, I'd like to know, do robots dream of colonizing the galaxy?
Ah, people. Little do you know, there is no one inside.
Except perhaps HAL.
Ann
Color Commentator
-
Chris Peterson
- Abominable Snowman
- Posts: 18612
- Joined: Wed Jan 31, 2007 11:13 pm
- Location: Guffey, Colorado, USA
- Contact:
Re: Why do we assume that an alien technological civilization would already have colonized the Milky Way?
Colonize, no. As you say, to what point? Even if those robots were somehow interested in reproducing themselves continuously, why would they choose planets? Space is much bigger.
But exploration would seem to provide a reasonable motive. And if you measure your existence in millions of years, light-speed communication between different parts of the galaxy isn't really much of a problem.
Chris
*****************************************
Chris L Peterson
Cloudbait Observatory
https://www.cloudbait.com
*****************************************
Chris L Peterson
Cloudbait Observatory
https://www.cloudbait.com
Re: Why do we assume that an alien technological civilization would already have colonized the Milky Way?
Ann -Ann wrote: ↑Fri Aug 09, 2024 4:07 am Thank you, Orca, for that extremely thoughtful input. Thanks to you too, Chris, for your answer to Orca. I agree with all of the points from both of you.
What I can't figure out is why an army of robots would want to colonize the Milky Way. What would be the point?
Do Androids Dream of Electric Sheep, asked Philip K. Dick. For myself, I'd like to know, do robots dream of colonizing the galaxy?
Ah, people. Little do you know, there is no one inside.
Except perhaps HAL.
Ann
I can't, oughtn't, and won't, in my own words, outdo Orca's razor-sharp thoughtfulness, or Chris's density of technical wisdom, so instead I point to other writers whose words speak to your original question while acknowledging Orca's & Chris's contributions.
To summarize Ricahrd Brodie in Virus of the Mind, there is not really a good/bad "why/why not;" but there is a core command: "replicate!" (Chris might chime in to clarify?)
And, with stone outlasting flesh, IF 'replicate=true', THEN one might (and Cixin Liu does) conceive of a scenario where all sorts of AI spaceships outlive their biological occupants. On the right timescales, the galaxy might be filled with these tombs. (Orca's writing grasps this better than I do.)
Ann, I thought your prompt nicely triangulated the current moment's intersections of fact/fiction : evidence/speculation : history/projection : past/future. I like to think the moment we live in, post-Drake equation but pre-Contact, yada yada, post-Past but pre-Future...oops, I guess that's called Now...I like to think about how our current paradigms might shift with new information, and what that information might be.
So, my answer to "how colonizing the far end of the Milky Way" benefits us on Earth?
It advances our paradigm.
Sam