Let's talk Great Filter

I’ve always thought it would be interesting to explore the idea of a society of intelligent beings where life takes place on a seasonal timeframe in a similar way to some insects. One generation grows up together and never meets their parents or children. They learn together and through knowledge left behind by the last generation before the winter killed them off (seasons and years could be much longer on this planet). Each generation focuses on improving that knowledge and leaving tools behind for the next generation to allow them to achieve more in one lifetime. Then they mate and die, never knowing whether what they have left will survive the winter. It would be interesting to see how this affected priorities wrt space travel, expansion etc., and therefore their potential visibility to us.


Yeah mismatching time scales could be a big deal, rocks as life, to them geologic time is normal speed. Or the opposite, they move / think / exist in computer scale time where a nanosecond is an eternity.

It’s like I’m reading a book… and it’s a book I deeply love. But I’m reading it slowly now. So the words are really far apart and the spaces between the words are almost infinite. I can still feel you… and the words of our story… but it’s in this endless space between the words that I’m finding myself now. It’s a place that’s not of the physical world. It’s where everything else is that I didn’t even know existed. I love you so much. But this is where I am now. And this who I am now. And I need you to let me go. As much as I want to, I can’t live your book any more.


I thought this animated short based on that premise was pretty clever:

ETA: If I remember right Alan Moore once penned a one-off comic story based on that idea too. The leader of an invading alien occupation force was filing a mission log reporting its frustration subjugating the inhabitants of the planet they were occupying because the beings of that planet existed on such a different time scale that there was no way to let them know they had been “conquered.”

In the end of the story the stress of the situation drives the invaders to madness and their entire occupying force withers to dust by the time the locals have a chance to take notice of their presence.


I remember an article about SETI in Scientific American around 15 years ago. A point made is that SETI is looking for signals MUCH more powerful than we can transmit. If a duplicate Earth were place even at the very closest star system, Alpha Centauri, we likely wouldn’t detect its radio signals. The exception was if they were transmitting at full power with their Arecibo telescope, and we were listening with ours.

No doubt receivers have gotten more sensitive, but still. The closest star with a decent chance of having life is more than double the distance of Alpha Centauri.

It may well be that civilizations get more energy efficient. Since our receivers - including those on satellites - are more sensitive, we’re not using 100ft dishes to transmit to communications satellites any more. Internet use means that we use undersea cables more than ever. (Even at the speed of light, relaying data via geosynchronous orbit adds a large delay.) We’re starting to use lasers instead of radios for satellite communications.

Which brings us to Optical SETI: Apparently we can count individual photons and detect coherent light, making it far better for interstellar communications.

The galaxy could be dotted with civilizations, most trapped in their star systems by the vast distance between stars, and even being more advanced they might not be detectable by radio.


There is a relatively recent event that will have an effect on broadcast monitoring aliens… Aliens who have started their trip to Earth based upon “radio” broadcasts may find themselves repulsed when they reach the Kardashian Horizon.


After Long Silence by Sheri S. Tepper

Humankind has colonized the planet Jubal, but only to a point. It is the massive crystal Presences which seem to hold true dominion. In some they inspire awe, in others dread. All that is known for certain is that they restrict travel and technology--and that they can be deadly. It is suspected that the crystals are both alive and intelligent. And before those who would do so can simply destroy them, the Presences must be convinced to break their long silence.

Check out Lockstep by Karl Schroeder.


When they say it’s a projection or hologram, what they’re really saying is something more like we are the artefacts of a projection, not that we are running out some algorithm. There’s a close analogy in explaining mathematical projections down from higher dimensions. To be a dimensional projection is sort of like being the shadow of something. The hologram idea is the idea that by looking at the “shadow” of a shape, or the outside of a volume of space (in the physics sense) then you have all of the information about the structure of that shape, or the inside of that volume of space. I hope I’m making sense. It’s more of a linking principle, very similar to mapping in mathematics.

Matt Parker does an excellent explanation of projections here. This is sort of what they mean by the idea that the universe is a hologram.

Scan to 35:25 for the part where he starts talking about 4-th dimensional cubes.

All in all, it’s actually a lot less mystical than it sounds at first blush.


Ooh, I stand corrected. I should double-check the videos more often. Thanks!

My tangent applied to Simulated Reality, not the Holographic Principle.

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That’s where I’d put my money.

We are almost certainly not alone. However, we are also almost certain to never meet any extra-solar species, for the simple reason that it turns out that Einstein was right about the whole speed-of-light-is-a-hard-limit thing.

The most parsimonious explanation for the Fermi Paradox is that interstellar travel is a practical engineering impossibility.

We might, at some point in the future, detect some sign of extra-solar life (which, as mentioned above, is much more difficult to do than is assumed by many armchair geeks). But we ain’t ever getting together for a chat.


As a planet, we can’t even come to agreement on whether or not Jesus was a person 2000 years ago, how the hell are we so certain that some Salarins didn’t pop-by Wyoming in 1675, pick up a baker’s dozen of Commanche, and then scamper back out of our field of surveillance?

I’d speculate we have no way of being certain that no-thing visited Earth prior to the 1950s or so.


@William_Holz already hit the point. But yeah I was referring to the theory we could possible be a simulation program.

I have heard of the hologram one as well, which is also interesting, but thanks for the video link! I’ll check it out after the kids are in bed.

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As my friend once put it: “Why would an advanced species come here to kidnap humans and give them anal probes when after 50 years, all they’ve learned is that one in ten really don’t mind the probe so much?”


That’s really interesting - Professor Brian Cox dedicated a whole documentary to this subject and you’ve destroyed it with one image.

If the sphere of our influence is really so small, however - then the galaxy or universe is to all intents and purposes, still empty, right? I mean teeming with life that we have little hope of interacting with is not an appreciably different scenario from our perspective - apart from the receding risk of a Great Filter (knowing our capacity for risk compensation, this may not be a good thing).

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That tiny dot still contains a lot of stuff, though; it’s a sphere with a ~100 light year radius.

This is why Douglas Adams made such a song and dance about how unimaginably big the universe is. Even the people who know that it’s really, really big often don’t properly grasp how truly big it is. :slightly_smiling:


If that 100 LY sphere contains just over 100 G Stars, then I suspect we will need to examine an area far greater than this to have much of a chance of finding playmates.


Or “A Deepness In the Sky” by Vernor Vinge


One nice little theory that I have heard ties in the lack of obsevable aliens with the problem of dark energy and missing matter.
The aliens are there,they’re just inside dyson spheres, so we can’t even see the stars they inhabit.


I wonder if even Dyson himself had an inkling of what a mind-bogglingly vast enterprise such a thing would be.

Has anyone crunched the numbers on that? Would your star even still be going when you finished?


Life itself is the alien. It successfully colonized once the earth was cool enough.

To me this means one of two things:

Either we are the descendants of the monocellular (or maybe even simpler) aliens,


They will be back to suck the oil and water from the planet to power their ships someday, and they are gonna be pissed about what we did to their gas station.