# Is the universe old or young? **URL:** \ **Category:** Great Debates\ **Created:** [April 23, 2022, 10:17pm UTC](https://boards.straightdope.com/t/is-the-universe-old-or-young/963334 "2022-04-23T22:17:54Z")\ **Posts on this page:** 20\ **Page:** 10
**Author:** ![k9bfriender](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/k9bfriender/32/3283_2.png) [@k9bfriender](https://boards.straightdope.com/u/k9bfriender)\ **Post date:** [May 1, 2022, 7:11pm UTC](https://boards.straightdope.com/t/is-the-universe-old-or-young/963334/181 "2022-05-01T19:11:53Z")
> [@eburacum45](#): > > This suggests to me that the galaxy is full of million-year-old+ civilisations. I’m prepared to accept that, but it is difficult to explain why none of those million-year-old+ civilisations have sent out exponentiating probes. The million year perspective is what is needed to grok the difficulties in the paradox. Think of where humanity will be in a million years. If someone thinks that we _won’t_ have an interstellar presence and a civilization detectable from far, far away, then they need to explain why. If they don’t think that alien civs would develop that way, and follow a similar path, they need to explain why humanity is unique in that it will. There tend to be a lot of assertions that it would require the entire output of a civilization in order to start this process, but nothing could be further from the truth. If we build a single self contained asteroid colony, then that’s all that is needed to continue that propagation across the entire reachable universe. It would not require the civ to gather its resources to send a ship halfway across the galaxy to a particular star, it would just be the colony growing up until some elements of it find another rock to start living on. Rinse and repeat for a few millions years, and you’ve colonized a good chunk of the galaxy without even trying. And if we are not into colonization, then we would still want resources. If we build an automated asteroid mining operation that can replicate itself, something that is an engineering challenge, to be sure, but not in any way a physical impossibility, why would we _not_ send them further and further out to gather more and more resources for our use? ---
**Author:** ![wolfpup](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wolfpup/32/10618_2.png) [@wolfpup](https://boards.straightdope.com/u/wolfpup)\ **Post date:** [May 1, 2022, 7:25pm UTC](https://boards.straightdope.com/t/is-the-universe-old-or-young/963334/182 "2022-05-01T19:25:04Z")
> [@k9bfriender](#): > > Personally, I find the reasons given that no alien intelligence ever would embark on such endeavors to be unpersuasive. It’s no more oddly specific than opening gold mines where there is gold, or removing mountains to get at the coal underneath. No, it’s more like opening gold mines on a planet orbiting ULAS J0744+25, which happens to be 775,000 light-years away. > [@Jackknifed\_Juggernaut](#): > > But we ARE undoubtedly unique on this planet. There have been a billion species of life on earth, and only 1 that evolved the intelligence we have. Not true. There are at least a dozen hominins in the fossil record that are comparable to us in intelligence, and at least one, _homo neanderthalensis_, that may actually have been smarter. It just happens that only one became dominant and ultimately survived the others. [![](https://i.imgur.com/gSykNNV.jpg) ](https://i.imgur.com/gSykNNV.jpg) ---
**Author:** ![k9bfriender](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/k9bfriender/32/3283_2.png) [@k9bfriender](https://boards.straightdope.com/u/k9bfriender)\ **Post date:** [May 1, 2022, 7:32pm UTC](https://boards.straightdope.com/t/is-the-universe-old-or-young/963334/183 "2022-05-01T19:32:03Z")
> [@wolfpup](#): > > No, it’s more like opening gold mines on a planet orbiting ULAS J0744+25, which happens to be 775,000 light-years away. Why would they do that, when there are gold mines to be opened in their own solar system, or if that’s used up, the next one over? Now, eventually, as they expand in their collection efforts, maybe they end up reaching out that far, in fact, that seems inevitable. But what makes you think that they would _start_ with one 775,000 light years away? The excavator meant to go to ULAS J0744+25 was created in ULAS J0744+24, which is only 774,995 light years away. And the excavator that created it was made in ULAS J0744+23 which is only 774,990 light years away, and so on. > [@wolfpup](#): > > There are at least a dozen hominins in the fossil record that are comparable to us in intelligence, and at least one, _homo neanderthalensis_ , that may actually have been smarter. It just happens that only one became dominant and ultimately survived the others. Which of them invented spaceflight? ---
**Author:** ![wolfpup](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wolfpup/32/10618_2.png) [@wolfpup](https://boards.straightdope.com/u/wolfpup)\ **Post date:** [May 1, 2022, 7:51pm UTC](https://boards.straightdope.com/t/is-the-universe-old-or-young/963334/184 "2022-05-01T19:51:50Z")
> [@k9bfriender](#): > > Why would they do that, when there are gold mines to be opened in their own solar system, or if that’s used up, the next one over? We’ll probably someday be doing some asteroid mining of our own, or perhaps extraterrestrial planetary mining. My point is that when you start dealing with typical interstellar distances, you’ve got a whole new level of challenge with some absolute physical constraints. It’s this “galactic colonization” fantasy that I find implausible. > [@k9bfriender](#): > > Which of them invented spaceflight? The only one that survived. But it could have been any of them, and multiple species of _Hominidae_ could in theory have co-existed and co-evolved. I reject the idea that _homo sapiens_ is some sort of unique “one chance out of 100 billion” miracle, but rather that something like it was virtually inevitable once evolution was well underway. And if it happened here, it almost certainly happened in millions of other equally hospitable places. ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [May 1, 2022, 7:55pm UTC](https://boards.straightdope.com/t/is-the-universe-old-or-young/963334/185 "2022-05-01T19:55:19Z")
> [@Mijin](#): > > And, in terms of likelihood, I’d say “no advanced ETs” is the frontrunner out of those 3 options. I wasn’t clear enough about no time to reach us yet. That would include all the time for existing intelligent beings to be able to launch an interstellar probe. > [@](#): > > Because “they’re hiding” requires every individual of every civilization of every species to always choose to hide, for millions of years. I Eventually yes, millions of years, but the question is why haven’t we seen them yet/ The answer is simple, we have only had the ability to see them for a brief period unless they dropped by and introduced themselves, which they didn’t. So if they are hiding they haven’t had to do it for very long yet. But I still see a problem with the idea that no other intelligent beings exist in the universe right now, there are too many opportunities. So either they didn’t get here yet, or they’re hiding. I don’t buy that they don’t exist yet at a comparable level of intelligence as humans, or greater. ---
**Author:** ![Babale](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/babale/32/15666_2.png) [@Babale](https://boards.straightdope.com/u/Babale)\ **Post date:** [May 1, 2022, 7:59pm UTC](https://boards.straightdope.com/t/is-the-universe-old-or-young/963334/186 "2022-05-01T19:59:58Z")
> [@wolfpup](#): > > Not true. There are at least a dozen hominins in the fossil record that are comparable to us in intelligence, and at least one, _homo neanderthalensis_ , that may actually have been smarter. It just happens that only one became dominant and ultimately survived the others. Yes, but they are all of our line. Intelligence evolved once and was present in all these hominids to varying degrees. ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [May 1, 2022, 8:08pm UTC](https://boards.straightdope.com/t/is-the-universe-old-or-young/963334/187 "2022-05-01T20:08:09Z")
> [@Babale](#): > > No. I am assuming that there was plenty of time for life, including intelligence, to evolve before us. Even if we posit Earth was in the first generatipn of life bearing planets, life could have settled on intelligence in the Mesozoic instead of now, and even though the Mesozoic ended just a blink of an eye ago on a stellar scale, it’s an eternity on the civilization scale. So a civilization that arose when we were in the Mesozoic would have had time to conquer the whole observable universe. This is where we disagree. Going back to the beginning, if they don’t have faster than light travel, even with great technological superiority and millions of years head start it could take much much longer than for any probe to arrive here. ---
**Author:** ![wolfpup](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wolfpup/32/10618_2.png) [@wolfpup](https://boards.straightdope.com/u/wolfpup)\ **Post date:** [May 1, 2022, 8:14pm UTC](https://boards.straightdope.com/t/is-the-universe-old-or-young/963334/188 "2022-05-01T20:14:28Z")
> [@Babale](#): > > Yes, but they are all of our line. Intelligence evolved once and was present in all these hominids to varying degrees. That sounds to me like just a restatement of the fact that any two species are ultimately related, and this remains true if they are of a different genus, different family, different order, and so on up the biological taxonomy. There is always a common ancestor. Furthermore, there is speculation that if the dinosaurs had not been wiped out, some version would have evolved human-like intelligence by now, and probably human-like technological capabilities. My point is that human-level intelligence is not some incredibly rare accident that may only have happened once in the entire galaxy, but rather that we are just one of millions of statistically probable outcomes that have happened throughout the galaxy wherever life formed and set evolution in motion. > [@TriPolar](#): > > if they don’t have faster than light travel This is another one of my bugaboos. If FTL travel or information transmission is possible, then our whole fundamental concept of space and time is completely wrong. And that seems unlikely. ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [May 1, 2022, 8:17pm UTC](https://boards.straightdope.com/t/is-the-universe-old-or-young/963334/189 "2022-05-01T20:17:27Z")
> [@k9bfriender](#): > > It doesn’t require any such “single minded effort” any more than it was a “single minded effort” that mined all that iron out of the ground that is now in buildings, or the oil that you put in your car. Individuals and groups of individuals working to exploit resources is the entire history of the human race, and I would say the entire history of life itself. Do you have any idea how much time and resources humans have put into the mining of iron on this planet, and all that not making a serious dent in our iron supply. Your analogies are way out of scale and proportion, the tiny iron mines on this planet are nothing compared to the consumption of resources you imagine. How do you think that would happen? Given enough incentive we got a man to the moon but not finding anything valuable there we haven’t even tried to go back. What motivates an over-populated planet to start scavenging all of it’s resources nearby in space just for the pipe dream of finding something worthwhile out among the stars? There were people sure we would be on Mars 4 years after landing on the moon, and traveling to the stars by now. Turns out some problems are trickier to realize than to imagine. ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [May 1, 2022, 8:22pm UTC](https://boards.straightdope.com/t/is-the-universe-old-or-young/963334/190 "2022-05-01T20:22:09Z")
> [@wolfpup](#): > > This is another one of my bugaboos. If FTL travel or information transmission is possible, then our whole fundamental concept of space and time is completely wrong. And that seems unlikely. I couldn’t say myself, but if the vast distance between stars is reduced to nothing timewise then the universe will become a messy place. ---
**Author:** ![k9bfriender](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/k9bfriender/32/3283_2.png) [@k9bfriender](https://boards.straightdope.com/u/k9bfriender)\ **Post date:** [May 1, 2022, 8:23pm UTC](https://boards.straightdope.com/t/is-the-universe-old-or-young/963334/191 "2022-05-01T20:23:27Z")
> [@wolfpup](#): > > My point is that when you start dealing with typical interstellar distances, you’ve got a whole new level of challenge with some absolute physical constraints What physical constraints are you talking about? There are no barriers between solar systems. At what point do we decide that we have enough? > [@wolfpup](#): > > It’s this “galactic colonization” fantasy that I find implausible. I think that’s just because you aren’t thinking in timescales of millions of years. (And no one is having a “fantasy”, so use of such belittling words starts turning this from an interesting and speculative discussion into a much less interesting attempt at barely veiled insults towards those you disagree with. I can’t stop you from doing so, but I _can_ stop taking your posts seriously.) Ten million years from now, do you think that we will still be limited to only the resources in our own solar system? > [@wolfpup](#): > > I reject the idea that _homo sapiens_ is some sort of unique “one chance out of 100 billion” miracle, I mean, if you simply reject it out of hand, then there’s not much point in further discussing it, I suppose. > [@wolfpup](#): > > but rather that something like it was virtually inevitable once evolution was well underway. And if it happened here, it almost certainly happened in millions of other equally hospitable places. That makes two assumptions on your part. One that evolution is well underway in many places, and isn’t stuck at procryptic life, as life was on Earth for the first couple billion years. And the other is that you extrapolate that into an “almost certainly” without any justification. > [@TriPolar](#): > > I wasn’t clear enough about no time to reach us yet. That would include all the time for existing intelligent beings to be able to launch an interstellar probe. So, what prevented any existing intelligent being from evolving until a few million years ago? ---
**Author:** ![k9bfriender](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/k9bfriender/32/3283_2.png) [@k9bfriender](https://boards.straightdope.com/u/k9bfriender)\ **Post date:** [May 1, 2022, 8:28pm UTC](https://boards.straightdope.com/t/is-the-universe-old-or-young/963334/192 "2022-05-01T20:28:36Z")
> [@wolfpup](#): > > That sounds to me like just a restatement of the fact that any two species are ultimately related, and this remains true if they are of a different genus, different family, different order, and so on up the biological taxonomy. If you have a line of species that develops higher intelligence, and it is only ones in that line that have, then why would you think that that would provide evidence that other lines would? > [@wolfpup](#): > > Furthermore, there is speculation that if the dinosaurs had not been wiped out, some version would have evolved human-like intelligence by now, and probably human-like technological capabilities. Speculation based on what? They had a hundred sixty five million years, didn’t do shit with it. Hominids have been here for only 4 million, and we’ve obviously come much further in that time. > [@wolfpup](#): > > My point is that human-level intelligence is not some incredibly rare accident that may only have happened once in the entire galaxy, but rather that we are just one of millions of statistically probable outcomes that have happened throughout the galaxy wherever life formed and set evolution in motion. How do you draw that conclusion, and more importantly, if that is the case, and that comes back to the same question over and over again, **where are they?** > [@wolfpup](#): > > This is another one of my bugaboos. If FTL travel or information transmission is possible, then our whole fundamental concept of space and time is completely wrong. And that seems unlikely. FTL in this thread is 100% strawman. It has only been mentioned by those on the side of believing that the universe is crammed full of invisible aliens. ---
**Author:** ![k9bfriender](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/k9bfriender/32/3283_2.png) [@k9bfriender](https://boards.straightdope.com/u/k9bfriender)\ **Post date:** [May 1, 2022, 8:29pm UTC](https://boards.straightdope.com/t/is-the-universe-old-or-young/963334/193 "2022-05-01T20:29:55Z")
> [@TriPolar](#): > > Do you have any idea how much time and resources humans have put into the mining of iron on this planet, and all that not making a serious dent in our iron supply. And yet, it’s something that we do. And it doesn’t require single minded dedication to it, or any of the other claims made in the thread. > [@TriPolar](#): > > the tiny iron mines on this planet are nothing compared to the consumption of resources you imagine Exactly, which is why we would want those resources. Not sure what point you are trying to make by pointing out the vast resources available in space. > [@TriPolar](#): > > How do you think that would happen? Lots of ways, but are you actually looking for a technical description? I’d happily write up pages on that, but I suspect that you meant that as a rhetorical question, so actually answering it would be a complete waste of my time. Let me know if you are _actually_ interested, and I’ll think about putting forth the effort to answer. > [@TriPolar](#): > > What motivates an over-populated planet to start scavenging all of it’s resources nearby in space just for the pipe dream of finding something worthwhile out among the stars? You keep going back to the idea that this would require a planetary effort with absolutly no justification. The reason for getting those resources would be to have them. Why do you think that an overpopulated planet _wouldn’t_ want more resources? > [@TriPolar](#): > > pipe dream of finding something worthwhile out among the stars? What are you even talking about here? We _know_ what is in asteroids, and we know exactly how worthwhile they would be to mine. And why are you saying anything about “among the stars”? Is that 100% red herring, or do you actually think that there are no asteroids in our own solar system, and that we’d have to go thousands of light years away to find one? > [@TriPolar](#): > > There were people sure we would be on Mars 4 years after landing on the moon, and traveling to the stars by now. Turns out some problems are trickier to realize than to imagine. Mostly for political reasons, but there’s a lot of FUD responsible for that. Anyway… Are you claiming that, over the next 10 million years, we will not colonize or mine a single asteroid? If so, that’s a pretty big claim, but if that’s your position, so be it. If not, then explain why we stop. ---
**Author:** ![wolfpup](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wolfpup/32/10618_2.png) [@wolfpup](https://boards.straightdope.com/u/wolfpup)\ **Post date:** [May 1, 2022, 8:49pm UTC](https://boards.straightdope.com/t/is-the-universe-old-or-young/963334/194 "2022-05-01T20:49:27Z")
> [@k9bfriender](#): > > What physical constraints are you talking about? There are no barriers between solar systems. The speed of light is such a physical constraint. I don’t doubt that science and technology will discover and produce mind-boggling wonders in the future, but that’s not the same as saying that one of the most fundamental foundations of physics is completely wrong. > [@k9bfriender](#): > > I think that’s just because you aren’t thinking in timescales of millions of years. (And no one is having a “fantasy”, so use of such belittling words starts turning this from an interesting and speculative discussion into a much less interesting attempt at barely veiled insults towards those you disagree with. I didn’t intend anything I said to be “belittling”, and I apologize if it seemed that way. I guess it’s just frustrating that this concept is so frequently presented as a self-evident truth about the behaviours of sufficiently advanced civilizations. As for timescales of millions of years, if we’re talking about the quest for resources I’d speculate it’s unlikely that the resources of an entire planetary system (most of which is likely to be resource-rich yet uninhabitable) would be exhausted in any foreseeable timeframe. And you were talking about essentially mining operations for resources. Doing that on an interstellar scale would require resource planning with millions of years of lead time. Is that realistic for any conceivable civilization? > [@k9bfriender](#): > > > [@wolfpup](#): > > > > I reject the idea that _homo sapiens_ is some sort of unique “one chance out of 100 billion” miracle, > > I mean, if you simply reject it out of hand, then there’s not much point in further discussing it, I suppose. Discuss, or don’t discuss, whatever you like. The question is this. What is more likely – that we are absolutely unique in the entire galaxy of millions or billions of potentially life-bearing planets, or that we’re just typical, just one among a great many? > [@k9bfriender](#): > > They had a hundred sixty five million years, didn’t do shit with it. Hominids have been here for only 4 million, and we’ve obviously come much further in that time. I’m not an evolutionary biologist, but the longevity of dinosaurs is a testament to their evolutionary success at that point. They didn’t evolve in any particularly notable ways (as far as we know) because they didn’t need to. Why did hominids evolve relatively rapidly? Possibly because of competition and scarcer resources. I really don’t know, but the same factors could have affected any successful dominant species. > [@k9bfriender](#): > > … that comes back to the same question over and over again, **where are they?** Many possible reasons have already been given, all quite plausible. Among them: the sheer vastness of space, both theoretical and practical speed limitations, the relative undetectability of long-distance radio waves even in theory due to noise thresholds, and the problem of knowing what to look for, among others. > [@k9bfriender](#): > > FTL in this thread is 100% strawman. It’s not a strawman, it’s a physical reality, and showing it to be wrong requires dismantling the very foundations of physics. ---
**Author:** ![Mijin](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mijin/32/9369_2.png) [@Mijin](https://boards.straightdope.com/u/Mijin)\ **Post date:** [May 1, 2022, 9:40pm UTC](https://boards.straightdope.com/t/is-the-universe-old-or-young/963334/195 "2022-05-01T21:40:28Z")
> [@TriPolar](#): > > Eventually yes, millions of years, but the question is why haven’t we seen them yet/ The answer is simple, we have only had the ability to see them for a brief period unless they dropped by and introduced themselves, which they didn’t. So if they are hiding they haven’t had to do it for very long yet. No, this conflates two different things. If we’re talking about what we can _see_, well, our field of view is huge, indeed the entire observable universe. So they don’t need to come to us. (Yes, we can only see EM radiation, and to a low granularity (and, with **much** worse resolution, neutrinos, gravitons etc), but that’s a different point. The point is, no, they don’t necessarily need to come here). If we’re talking about aliens actually _visiting_, then no, it doesn’t necessarily need to happen at the same time as we’re looking. An obelisk on the moon would have done nicely, for example. > [@](#): > > But I still see a problem with the idea that no other intelligent beings exist in the universe right now, there are too many opportunities. So either they didn’t get here yet, or they’re hiding. I don’t buy that they don’t exist yet at a comparable level of intelligence as humans, or greater. The problem that you are not seeing is that no-one is making a claim here but you. I am not saying there are no advanced ETs. I am saying that our (lack of) observations of, for example, phenomena that block or emit EM waves on a significant scale is a very important data point, that constrains certain hypotheses about ETs. ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [May 1, 2022, 9:49pm UTC](https://boards.straightdope.com/t/is-the-universe-old-or-young/963334/196 "2022-05-01T21:49:57Z")
> [@k9bfriender](#): > > So, what prevented any existing intelligent being from evolving until a few million years ago? Nothing I know of. Again I will point out, if any did evolve they have not gotten to where we can see them yet or they are hiding. It doesn’t matter why they didn’t get here yet, it could be because they only just evolved intelligence or they are too far away or they are just lazy. What we know is that we haven’t encountered them yet. ---
**Author:** ![Mijin](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mijin/32/9369_2.png) [@Mijin](https://boards.straightdope.com/u/Mijin)\ **Post date:** [May 1, 2022, 9:56pm UTC](https://boards.straightdope.com/t/is-the-universe-old-or-young/963334/197 "2022-05-01T21:56:12Z")
> [@wolfpup](#): > > There are an estimated 100 billion to as many as 400 billion stars in our galaxy, and from what we’ve seen so far the majority of them probably have planets. If only a fraction of those are in the habitable zone for life as we know it, and only a fraction of that fraction evolved life, and only a smaller fraction still evolved intelligence, that still leaves the potential for millions of technologically advanced civilizations out there. We have no idea about the likelihood overall. The tiny fractions could add up to 1 / tree(3) and we’re unique. Though it is an encouraging sign that some previous unknowns, like the average number of planets orbiting stars are quite high. > [@wolfpup](#): > > And I find the claim that at least a few such civilizations would engage in the sequential colonization behaviour you describe – either by successively propagating colonies across many star systems or doing so with self-replicating robots – to be quite unpersuasive. It’s oddly specific behaviour that I continue to maintain does require a commensurately specific motivation. Again, I think you have this exactly backwards. WRT EM radiation, for example, I don’t need to posit any specific motivation for a species to emit, refract or absorb significant EM radiation. Yes, we talk about Dyson spheres and the like, but that’s only to illustrate that we can already hypothesize reasons to build such structures i.e. we already have reason to disfavor the explanation that there is no benefit to emit, refract or absorb significant amounts of EM radiation. But it wouldn’t matter if an alien species built a giant microwave emitter to snerf the smorgal field…any EM radiation we see could be evidence of an ET civilization even if we have no idea what they are doing and why. > [@wolfpup](#): > > You apparently hold the seemingly contradictory views that there are probably no other technologically advanced civilizations in the galaxy, but that if there were, there would be so many of them that at least a few would be engaged in large-scale galactic colonization I have been very clear that I hold no position either way. But to be clear on the spreading across the galaxy thing, and I have already said this many times: it would only take one faction of one species (or artificial lifeform) to start such an endevour to potentially litter the whole galaxy. So I would disagree with the proposition about needing many advanced ETs to exist. ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [May 1, 2022, 10:02pm UTC](https://boards.straightdope.com/t/is-the-universe-old-or-young/963334/198 "2022-05-01T22:02:15Z")
> [@Mijin](#): > > The problem that you are not seeing is that no-one is making a claim here but you. I am not saying there are no advanced ETs. I am saying that our (lack of) observations of, for example, phenomena that block or emit EM waves on a significant scale is a very important data point, that constrains certain hypotheses about ETs. I’m not arguing against anybody. One of the possible reasons we have not encountered alien intelligence is because it doesn’t exist. I stated that was the least likely of the 3 possibilities I listed. I don’t see why I have to justify that as a possibility even if it seems improbable. The other 2 possibilities for why we have not encountered alien intelligence is that they are hiding or are too far away for us to detect them. I suppose I have to add that they aren’t hiding and we just haven’t noticed, but I think that is falls under concept of being too far away or the concept of hiding. Maybe they aren’t actively hiding and we still can’t see them, but I don’t see what difference that makes. ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [May 1, 2022, 10:24pm UTC](https://boards.straightdope.com/t/is-the-universe-old-or-young/963334/199 "2022-05-01T22:24:21Z")
> [@k9bfriender](#): > > Exactly, which is why we would want those resources. Not sure what point you are trying to make by pointing out the vast resources available in space. I’ll go back and stop discussing answering your questions. Your sci-fi fantasies present absolutely no reason why we haven’t encountered alien intelligence yet. Are you making the argument that we haven’t encountered intelligent aliens yet because they are spreading self-replicating habitats through the universe? ---
**Author:** ![Babale](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/babale/32/15666_2.png) [@Babale](https://boards.straightdope.com/u/Babale)\ **Post date:** [May 1, 2022, 11:11pm UTC](https://boards.straightdope.com/t/is-the-universe-old-or-young/963334/200 "2022-05-01T23:11:01Z")
> [@wolfpup](#): > > That sounds to me like just a restatement of the fact that any two species are ultimately related, and this remains true if they are of a different genus, different family, different order, and so on up the biological taxonomy. Sure, and that’s why it’s interesting to speculate over whether feathers and pterosaur fuzz evolved separately in two unrelated lineages, or if all archosaurs had a primitive fuzz that evolved into these two forms. Hominids all already had the intelligence due to an intelligent common ancestor. That doesn’t tell us anything about how likely evolution is to evolve. [Previous page](https://boards.straightdope.com/t/is-the-universe-old-or-young/963334.md?page=9) [Next page](https://boards.straightdope.com/t/is-the-universe-old-or-young/963334.md?page=11)