8 ms·

Very exciting news, if by exciting you mean horrifying. It would be near confirmation of the Great Filter.

HuShifang 6y ago
If it all holds up, it means that we saw evidence of alien life for a hundred-plus years (the "unknown absorbers") before we realized it and verified it. Point being, humans can be "slow on the uptake" (and not unreasonably so, given the distances, time scales, and complexities involved). See also the Silurian Hypothesis [0], which I think just got a lot more interesting as a thought experiment. [0]: https://www.theatlantic.com/science/archive/2018/04/are-we-earths-only-civilization/557180/ https://www.theatlantic.com/science/archive/2018/04/are-we-e...
- alquemist 6y ago
  > Was There a Civilization on Earth Before Humans? [...] Gavin and I don’t believe the Earth once hosted a 50-million-year-old Paleocene civilization. Betteridge's Law confirmed. We can track down fossils billions of year back by observing the way they shaped the encasing rocks, and not once have we noticed a ceramic shard, a metal bit or the silhouette of a plastic object.
  - c22 6y ago
    From the article: > There are fossils, of course. But the fraction of life that gets fossilized is always minuscule and varies a lot depending on time and habitat. It would be easy, therefore, to miss an industrial civilization that lasted only 100,000 years—which would be 500 times longer than our industrial civilization has made it so far.
    - alquemist 6y ago
      > And then there’s all that plastic. Studies have shown that increasing amounts of plastic “marine litter” are being deposited on the seafloor everywhere from coastal areas to deep basins, and even in the Arctic. Wind, sun, and waves grind down large-scale plastic artifacts, leaving the seas full of microscopic plastic particles that will eventually rain down on the ocean floor, creating a layer that could persist for geological timescales. Sandstones. Sandstones originate as far as hundreds of million years in the past. Occasionally they harbor fossils, which are indeed rare. But a lot of sandstone is made of sanded up organic material which we can readily identify, even if we can't point to the specific organism they originated from. We only need a tiny industrial-related grain of sand (ceramic, glass, metal, plastic traces) to point to a past civilization. Nobody ever noticed such a grain of sand.
      - phreeza 6y ago
        They we would not have access to petroleum, so no plastic.
      - c22 6y ago
        Sure, and the article mentions other possible signs of civilization as well, then it goes on to say: > So it might take both dedicated and novel detection methods to find evidence of a truly short-lived event in ancient sediments. In other words, if you’re not explicitly looking for it, you might not see it. That recognition was, perhaps, the most concrete conclusion of our study. I'm not bullish on pre-historic civilization, and neither is the article, but the takeaway is we may not have reason to expect that we'd have found these tiny industrialized traces without a search aimed specifically at them. As far as I know, such searches have not been carried out in earnest to date.
        alquemist 6y ago
        We've put old rocks under the electronic microscope. That's how we identified billion year old cyanobacteria fossils. While there is no readily available comprehensive record of who searched for microfossils by looking at what old rocks, with or without a microscope, it's not like it's a new idea. https://ucmp.berkeley.edu/bacteria/cyanofr.html https://ucmp.berkeley.edu/bacteria/cyanofr.html
        c22 6y ago
        I feel like we're talking past each other here. The very first sentence of your link says "The cyanobacteria have an extensive fossil record." In the next paragraph it says "Cyanobacteria are among the easiest microfossils to recognize. Morphologies in the group have remained much the same for billions of years..." So not a truly short-lived event in ancient sediments then.
gfodor 6y ago
Not if we live in a dark forest and I’m sure there are many other reasons to believe absence of evidence does not mean evidence of absence.
- vecter 6y ago
  It's unlikely we live in a dark forest. The resources necessary to execute entire civilizations across interstellar space would be literally astronomical.
  - TeMPOraL 6y ago
    They would be comparable to resources needed for sublight interstellar travel. If you can get a colony ship to the nearest start at 0.9 c, you can also send an equivalent-weight chunk of matter towards someone else's planet and don't slow down.
  - postalrat 6y ago
    How could you possibly know this.
saberdancer 6y ago
Why would it be confirmation of Great Filter? It's quite possible that life is abundant in the galaxy but that intelligent life is not common and especially industrialized civilizations.
- Jetroid 6y ago
  That's still a confirmation of the Great Filter; just that life on Earth has already passed through it.
  - pvaldes 6y ago
    (Ok. Can somebody explain what is all this fuss about filters?)
    - gremlinsinc 6y ago
      Essentially it's the fermi paradox. If life is out there, why aren't there signs? The universe should be teaming with life but isn't. There's a few reasons why... the Great Filter is a hypothesis that basically means almost all life hits a wall where it dies out no matter what. No life so far that we know has ever made it past this filter. Here's a good read on the subject: https://waitbutwhy.com/2014/05/fermi-paradox.html https://waitbutwhy.com/2014/05/fermi-paradox.html
      - CamperBob2 6y ago
        If life is out there, why aren't there signs? For the same reason the large dinosaurs died out. Life as we know it operates best within fairly narrow mass scales and energy level ranges. Those are both several orders of magnitude away from the quantities needed to produce effects observable at interstellar distances. The universe should be teeming with life but isn't. We currently have no good evidence that it is. That doesn't mean it isn't, just that our detection methods aren't yet up to the challenge. Basic information theory suggests that they may never be. Advanced civilizations will use coherent EM radiation for a limited time only. The radiation they do generate in the long term probably won't be wasted by letting it escape isotropically into space. Also, at some point they may come to understand that drawing attention to themselves isn't a good survival strategy. A civilization that is advanced enough for us to observe is also advanced enough to hide from us.
nafey 6y ago
We could have crossed the great filter already if there is a great filter between bacterial and sapien life forms
colordrops 6y ago
Or perhaps once a certain level of technology is reached, the civilization advances so fast as to no longer be recognizable. Perhaps it's not a filter but rather a lack of imagination. What appears to be the universe and all things to us could be a limited as a drop of water to a paramecium.
StanislavPetrov 6y ago
Only if you ignore the UFO footage and data released by the Pentagon (and others over the years). https://www.nytimes.com/2020/04/28/us/pentagon-ufo-videos.html https://www.nytimes.com/2020/04/28/us/pentagon-ufo-videos.ht...
- infradig 6y ago
  You mean these ones... https://m.youtube.com/watch?v=Q7jcBGLIpus https://m.youtube.com/watch?v=Q7jcBGLIpus

If it all holds up, it means that we saw evidence of alien life for a hundred-plus years (the "unknown absorbers") before we realized it and verified it. Point being, humans can be "slow on the uptake" (and not unreasonably so, given the distances, time scales, and complexities involved). See also the Silurian Hypothesis [0], which I think just got a lot more interesting as a thought experiment. [0]: https://www.theatlantic.com/science/archive/2018/04/are-we-earths-only-civilization/557180/ https://www.theatlantic.com/science/archive/2018/04/are-we-e...

alquemist 6y ago
> Was There a Civilization on Earth Before Humans? [...] Gavin and I don’t believe the Earth once hosted a 50-million-year-old Paleocene civilization. Betteridge's Law confirmed. We can track down fossils billions of year back by observing the way they shaped the encasing rocks, and not once have we noticed a ceramic shard, a metal bit or the silhouette of a plastic object.
- c22 6y ago
  From the article: > There are fossils, of course. But the fraction of life that gets fossilized is always minuscule and varies a lot depending on time and habitat. It would be easy, therefore, to miss an industrial civilization that lasted only 100,000 years—which would be 500 times longer than our industrial civilization has made it so far.
  - alquemist 6y ago
    > And then there’s all that plastic. Studies have shown that increasing amounts of plastic “marine litter” are being deposited on the seafloor everywhere from coastal areas to deep basins, and even in the Arctic. Wind, sun, and waves grind down large-scale plastic artifacts, leaving the seas full of microscopic plastic particles that will eventually rain down on the ocean floor, creating a layer that could persist for geological timescales. Sandstones. Sandstones originate as far as hundreds of million years in the past. Occasionally they harbor fossils, which are indeed rare. But a lot of sandstone is made of sanded up organic material which we can readily identify, even if we can't point to the specific organism they originated from. We only need a tiny industrial-related grain of sand (ceramic, glass, metal, plastic traces) to point to a past civilization. Nobody ever noticed such a grain of sand.
    - phreeza 6y ago
      They we would not have access to petroleum, so no plastic.
    - c22 6y ago
      Sure, and the article mentions other possible signs of civilization as well, then it goes on to say: > So it might take both dedicated and novel detection methods to find evidence of a truly short-lived event in ancient sediments. In other words, if you’re not explicitly looking for it, you might not see it. That recognition was, perhaps, the most concrete conclusion of our study. I'm not bullish on pre-historic civilization, and neither is the article, but the takeaway is we may not have reason to expect that we'd have found these tiny industrialized traces without a search aimed specifically at them. As far as I know, such searches have not been carried out in earnest to date.
      - alquemist 6y ago
        We've put old rocks under the electronic microscope. That's how we identified billion year old cyanobacteria fossils. While there is no readily available comprehensive record of who searched for microfossils by looking at what old rocks, with or without a microscope, it's not like it's a new idea. https://ucmp.berkeley.edu/bacteria/cyanofr.html https://ucmp.berkeley.edu/bacteria/cyanofr.html
        c22 6y ago
        I feel like we're talking past each other here. The very first sentence of your link says "The cyanobacteria have an extensive fossil record." In the next paragraph it says "Cyanobacteria are among the easiest microfossils to recognize. Morphologies in the group have remained much the same for billions of years..." So not a truly short-lived event in ancient sediments then.

gfodor 6y ago

Not if we live in a dark forest and I’m sure there are many other reasons to believe absence of evidence does not mean evidence of absence.

vecter 6y ago
It's unlikely we live in a dark forest. The resources necessary to execute entire civilizations across interstellar space would be literally astronomical.
- TeMPOraL 6y ago
  They would be comparable to resources needed for sublight interstellar travel. If you can get a colony ship to the nearest start at 0.9 c, you can also send an equivalent-weight chunk of matter towards someone else's planet and don't slow down.
- postalrat 6y ago
  How could you possibly know this.

saberdancer 6y ago

Why would it be confirmation of Great Filter? It's quite possible that life is abundant in the galaxy but that intelligent life is not common and especially industrialized civilizations.

Jetroid 6y ago
That's still a confirmation of the Great Filter; just that life on Earth has already passed through it.
- pvaldes 6y ago
  (Ok. Can somebody explain what is all this fuss about filters?)
  - gremlinsinc 6y ago
    Essentially it's the fermi paradox. If life is out there, why aren't there signs? The universe should be teaming with life but isn't. There's a few reasons why... the Great Filter is a hypothesis that basically means almost all life hits a wall where it dies out no matter what. No life so far that we know has ever made it past this filter. Here's a good read on the subject: https://waitbutwhy.com/2014/05/fermi-paradox.html https://waitbutwhy.com/2014/05/fermi-paradox.html
    - CamperBob2 6y ago
      If life is out there, why aren't there signs? For the same reason the large dinosaurs died out. Life as we know it operates best within fairly narrow mass scales and energy level ranges. Those are both several orders of magnitude away from the quantities needed to produce effects observable at interstellar distances. The universe should be teeming with life but isn't. We currently have no good evidence that it is. That doesn't mean it isn't, just that our detection methods aren't yet up to the challenge. Basic information theory suggests that they may never be. Advanced civilizations will use coherent EM radiation for a limited time only. The radiation they do generate in the long term probably won't be wasted by letting it escape isotropically into space. Also, at some point they may come to understand that drawing attention to themselves isn't a good survival strategy. A civilization that is advanced enough for us to observe is also advanced enough to hide from us.

nafey 6y ago

We could have crossed the great filter already if there is a great filter between bacterial and sapien life forms

colordrops 6y ago

Or perhaps once a certain level of technology is reached, the civilization advances so fast as to no longer be recognizable. Perhaps it's not a filter but rather a lack of imagination. What appears to be the universe and all things to us could be a limited as a drop of water to a paramecium.

StanislavPetrov 6y ago

Only if you ignore the UFO footage and data released by the Pentagon (and others over the years). https://www.nytimes.com/2020/04/28/us/pentagon-ufo-videos.html https://www.nytimes.com/2020/04/28/us/pentagon-ufo-videos.ht...

infradig 6y ago
You mean these ones... https://m.youtube.com/watch?v=Q7jcBGLIpus https://m.youtube.com/watch?v=Q7jcBGLIpus