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Here's a parameter I don't think the Fermi Equation takes into account: I call it "Fragile Universe", based off of the notion of the "Fragile" or "Vulnerable W

Here's a parameter I don't think the Fermi Equation takes into account: I call it "Fragile Universe", based off of the notion of the "Fragile" or "Vulnerable World Hypothesis" [1]. f_c is the parameter for the fraction of "civilizations that reach the technological level whereby detectable signals may be dispatched", so that handles the "Fragile World Hypothesis". Alien civilizations can wipe themselves out, exhaust resources, etc. before we get to see their detectable signals [2]. What the equation doesn't take into consideration is the possibility that an advanced species can trigger the destruction or total reset of the entire universe, eg. by nucleating the vacuum collapse. The first advanced species to reach that point could kill every species in the universe and start the whole thing over from scratch. This is an extreme version of the anthropic principle [3]. We exist because the universe hasn't been reset yet. By us or otherwise. Presumably we might be the first to get there. Universe fragility could be the reason we don't see aliens. We could be the very first, and we could wind up hitting the reset button. [1] https://nickbostrom.com/papers/vulnerable.pdf https://nickbostrom.com/papers/vulnerable.pdf ; tldr: advanced species can trivially wipe themselves out and will tend to do so. Not just nukes, but in the extreme, your average citizen can create grey goo at home with the press of a button that will turn the entire planet into paper clips. [2] It could be that the time frames in which advanced civilizations emit detectable signals are so geologically small as they shift into non-detectable modes (eg. dark forest, disinterest in expansion, shift into a higher plane of existence, etc.), but that's orthogonal to the discussion. [3] https://en.wikipedia.org/wiki/Anthropic_principle https://en.wikipedia.org/wiki/Anthropic_principle

ziddoap 2y ago
>eg. by nucleating the vacuum collapse. The first advanced species to reach that point could kill every species in the universe and start the whole thing over from scratch. How do you imagine the Universe resetting? Assuming the false vacuum decay occurs, I don't think any species (no matter how advanced) could reset the vacuum state back to a metastable state post-collapse. It does just appear to be the anthropic principle, but with some extra steps.
- echelon 2y ago
  Maybe it doesn't? Maybe there are lots of other universes, and we just happen to be in one of the metastable ones that hasn't collapsed yet.
jebarker 2y ago
Novice question here: What use is there in adding a term like that to the Drake equation? It seems like it's value would be completely uncertain (like other terms in the equation) and so you have overwhelming uncertainty in the output of the equation.
- andrewflnr 2y ago
  Your instinct is largely correct. This is a silly idea.
- simne 2y ago
  Right answer is - we don't know. Unfortunately, Drake equation now is just estimate, without any real data, as humanity just don't know example of any extraterrestrial life at all. And what even more sad, our empty knowledge is not because non-existence of life in Universe, but because our science is very young and we just don't have powerful enough instruments to detect et life. We could only be sure, life was not exist on Moon equatorial stripe on surface, but for example we cannot be sure about deep under-surface and about polar regions.
  - simne 2y ago
    Things are even worse for intelligent life. Because we only could understand et with similar to our level of sci/tech development, but what if we encounter civilization, even one magnitude older than our? For example, now our science have evidences about human civilizations up to somewhere 10k..50k years, and our current civilization oldest evidences are about 5k years. Imagine, how could look our civilization in 500k years? And if we use adequate considerations, human life was appear on Earth ~ 500 thousands years ago, and before was possible reptile civilization, for about 10 millions years, but our Earth become life planet ~ billion years, and exist planets in other star systems, which are tens billions years older than Earth. So what I mean, in our 5k years our civilization decided to re-circling resources and probably in ~ 100 years we could implement this decision and will become invisible to ets of our level. Imagine, what technologies would be available for magnitude older civilization. Could someone be sure about possibility of detection so much newer technologies? You may hear classification of seti scientists as Cygnus, Cancer and Pike. What I want to say, civilizations younger than our are detectable for us, but older are detectable only if them decided to contact us.
bluGill 2y ago
The universe is 93 billion light years across. No alien can reset it within time spans that matter to our solar system which has maybe 8 billion years left before our sun dies)
wat10000 2y ago
I don't think that solves it. The Fermi paradox is that based on the probabilities we estimate, we should see lots of aliens, and we don't. Thus something in our estimates must be wrong, but we don't know what. This fragility idea just shifts it from "we should see lots of aliens and we don't" to "the universe should have been destroyed by now and it hasn't been."
- DennisP 2y ago
  Actually the Drake equation may not say that: > When we take account of realistic uncertainty, replacing point estimates by probability distributions that reflect current scientific understanding, we find no reason to be highly confident that the galaxy (or observable universe) contains other civilizations, and thus no longer find our observations in conflict with our prior probabilities....When we update this prior in light of the Fermi observation, we find a substantial probability that we are alone in our galaxy, and perhaps even in our observable universe (53%–99.6% and 39%–85% respectively). ’ https://arxiv.org/abs/1806.02404 https://arxiv.org/abs/1806.02404

ziddoap 2y ago

>eg. by nucleating the vacuum collapse. The first advanced species to reach that point could kill every species in the universe and start the whole thing over from scratch. How do you imagine the Universe resetting? Assuming the false vacuum decay occurs, I don't think any species (no matter how advanced) could reset the vacuum state back to a metastable state post-collapse. It does just appear to be the anthropic principle, but with some extra steps.

echelon 2y ago
Maybe it doesn't? Maybe there are lots of other universes, and we just happen to be in one of the metastable ones that hasn't collapsed yet.

jebarker 2y ago

Novice question here: What use is there in adding a term like that to the Drake equation? It seems like it's value would be completely uncertain (like other terms in the equation) and so you have overwhelming uncertainty in the output of the equation.

andrewflnr 2y ago
Your instinct is largely correct. This is a silly idea.
simne 2y ago
Right answer is - we don't know. Unfortunately, Drake equation now is just estimate, without any real data, as humanity just don't know example of any extraterrestrial life at all. And what even more sad, our empty knowledge is not because non-existence of life in Universe, but because our science is very young and we just don't have powerful enough instruments to detect et life. We could only be sure, life was not exist on Moon equatorial stripe on surface, but for example we cannot be sure about deep under-surface and about polar regions.
- simne 2y ago
  Things are even worse for intelligent life. Because we only could understand et with similar to our level of sci/tech development, but what if we encounter civilization, even one magnitude older than our? For example, now our science have evidences about human civilizations up to somewhere 10k..50k years, and our current civilization oldest evidences are about 5k years. Imagine, how could look our civilization in 500k years? And if we use adequate considerations, human life was appear on Earth ~ 500 thousands years ago, and before was possible reptile civilization, for about 10 millions years, but our Earth become life planet ~ billion years, and exist planets in other star systems, which are tens billions years older than Earth. So what I mean, in our 5k years our civilization decided to re-circling resources and probably in ~ 100 years we could implement this decision and will become invisible to ets of our level. Imagine, what technologies would be available for magnitude older civilization. Could someone be sure about possibility of detection so much newer technologies? You may hear classification of seti scientists as Cygnus, Cancer and Pike. What I want to say, civilizations younger than our are detectable for us, but older are detectable only if them decided to contact us.

bluGill 2y ago

The universe is 93 billion light years across. No alien can reset it within time spans that matter to our solar system which has maybe 8 billion years left before our sun dies)

wat10000 2y ago

I don't think that solves it. The Fermi paradox is that based on the probabilities we estimate, we should see lots of aliens, and we don't. Thus something in our estimates must be wrong, but we don't know what. This fragility idea just shifts it from "we should see lots of aliens and we don't" to "the universe should have been destroyed by now and it hasn't been."

DennisP 2y ago
Actually the Drake equation may not say that: > When we take account of realistic uncertainty, replacing point estimates by probability distributions that reflect current scientific understanding, we find no reason to be highly confident that the galaxy (or observable universe) contains other civilizations, and thus no longer find our observations in conflict with our prior probabilities....When we update this prior in light of the Fermi observation, we find a substantial probability that we are alone in our galaxy, and perhaps even in our observable universe (53%–99.6% and 39%–85% respectively). ’ https://arxiv.org/abs/1806.02404 https://arxiv.org/abs/1806.02404