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This is a compelling theory, especially the implication that humans are early. I do wonder whether we should see the evidence of spheres of growing alien influe
by GavinB 3y ago
This is a compelling theory, especially the implication that humans are early. I do wonder whether we should see the evidence of spheres of growing alien influence out in the stars, but instead we see a highly uniform universe in all directions.
This would indicate a few possibilities:
1. Expanding alien civilizations are relatively low impact and don't collect all of the energy of stars in ways that are visible to our current telescopes.
2. We are a very early civilization, civs are fairly rare, and we're relatively alone in the parts of the universe that we can see. Civs that are expanding in a grabby fashion started less recently in years than their distance in light years.
3. Aliens expand at close to the speed of light, so there are a lot out there but we won't see them until they're almost here.
4. Something that we have already noticed is actually evidence of grabby aliens, but it is happening in every direction so we assume that it is a natural phenomenon, because it is so uniform.
At the very least, it seems likely that we either we are alone in the galaxy, or expansion is very slow. The idea of "expanding in a bubble of influence close to the speed of light" seems implausible to me, just because of the vast amounts of energy required to accelerate and decelerate to relativistic speeds, not to mention protecting the cargo in transit--when you're flying at .9c, almost every other piece of matter in the universe is flying towards you at you at .9c. Accelerating tiny nanomachine von Neumann probes might be a solution, but how would they decelerate enough to not be destroyed on arrival?
It's all fascinating to think about, at least.
- taneq 3y ago> how would they decelerate enough to not be destroyed on arrival? Solar sail being pushed on by the destination star? Or to begin with, even just a “drouge” creating friction against interstellar gas?
- Matt_Mahgerfteh 3y agoYeah, it's like we're playing cosmic detective trying to figure out if there's anyone else out there in the universe. The fact that we haven't seen any clear signs of alien civilizations doing their thing is kind of mind-boggling. It's like, are they just really subtle about it, or are we just super early to the party?
- 7thaccount 3y agoOr if there is some dark foresting going on or one of a dozen other theories
- deleted 3y ago[deleted]
- throwawayqqq11 3y agoWhen you mine asteroids in orbit on a large scale around your star, the released dust/debris would form an IR halo around the star that would be very easy to detect and reveal your presence but we dont see any of it. So, early humans it propably is.
- ccheney 3y agoYour point on missing IR halos is valid, but don't overlook anomalies like Tabby's Star (KIC 8462852) [0]. Its odd dimming led to theories about alien megastructures like Dyson Spheres, though dust or comets are possible explanations. Still, Tabby's Star highlights the difficulty in excluding advanced alien activities with our current tech. [1] [0] https://en.wikipedia.org/wiki/Tabby%27s_Star https://en.wikipedia.org/wiki/Tabby%27s_Star [1] https://youtu.be/mZve2Oy3cFg?t=82 https://youtu.be/mZve2Oy3cFg?t=82
- matthewdgreen 3y agoThis person [1] ran a data search for stars with a similar light profile (“slow dippers”) to Tabby/Boyajian’s Star, and claims to have found a cluster of similar stars in the region. But the results are not particularly high confidence and are probably just data artifacts. [1] https://iopscience.iop.org/article/10.3847/1538-3881/ac3416 https://iopscience.iop.org/article/10.3847/1538-3881/ac3416
- exe34 3y agoWould you pollute your environment with missiles at orbital speed? I suppose given our stellar stewardship of the atmosphere, maybe they're like us.
- AnimalMuppet 3y agoAliens collecting all the light/electromagnetic radiation from stars would be an interesting way to get dark matter. That's one place it could fit. And, if our theories are right, we're at 4.9% regular matter and 26.8% dark matter, so dark matter is five times as much as regular matter, so that's a lot of aliens...
- bhickey 3y agoWhat you're suggesting doesn't make sense. Dark matter isn't non-luminous matter. It's matter that only interacts gravitationally, but not electromagnetically. This means it doesn't undergo collisions and can't shed angular momentum. It forms a diffuse, largely uniform cloud throughout galaxies. The result is that galaxies are more dense further from the galactic core than we would predict from luminous matter alone.
- bqmjjx0kac 3y agoI'm speaking outside my area, but dark matter is not really confirmed to even exist?
- bhickey 3y agoIt's consistent with observational evidence. You are correct that no one has detected dark matter particles.
- revscat 3y agohttps://youtu.be/nbE8B7zggUg?si=QcBpuxSvXsGGxTKk https://youtu.be/nbE8B7zggUg?si=QcBpuxSvXsGGxTKk
- tsimionescu 3y agoIt's clearly confirmed that galaxies don't obey the known laws of quantum electrodynamics (QED) + general relativity (GR) if we assume they are made entirely of Standard Model particles. So, either QED is wrong (extremely unlikely) or GR is wrong (unlikely) or there is some matter that is not in the Standard Model (plausible). Dark matter corresponds to option 3 - and there are observations that conform some models of dark matter distribution that match quite well between different galaxies. There are other theories as well, such as MOND (modified Newtonian gravity) that explore option 2 (GR is wrong). Still, whatever the theory, it's clear that what is not happening is "aliens someone consuming all of the EM radiation from some stars". With anything resembling currently known physics, it's impossible to "consume" EM radiation in this way. Electric charge is always conserved, electrons and quarks don't disappear just because they move around, even with something like controlled fusion. A Dyson sphere would be an extremely hot visible object, not some dark point.
- c22 3y agoI like option 4. Perhaps some of the things we think are black holes are just grabby aliens.
- therockspush 3y agoWho knows what they've been grabbing. https://www.youtube.com/watch?v=u5qYH-Y3tQ4 https://www.youtube.com/watch?v=u5qYH-Y3tQ4
- cwillu 3y agoAlas, there's a fifth possibility: 5. Controlled transportation between the stars, sufficient for colonization, is sufficiently impractical that there are no grabby aliens within our light-cone.
- XorNot 3y agoThat itself would be quite interesting though, because based on what we know now it's merely difficult, not impossible with reasonably foreseeable technological improvements. The dynamics which would make it impossible on any known timespan don't seem currently observable.
- whizzter 3y agoI think a huge factor you don't account for here is that some of these technological improvements might imply a great-filter that we really haven't passed yet as humans, and the negative effects would affect most similarly expansionist and competitive races alike us since it might be questionable if there would be enough pressure on a non-competitive race to expand rather than just conserve local resources. Just with state-controlled nuclear weapons we've been on the brink of extinction a couple of times already, the energy levels required for star-travel implies this kind of destructive power being in the hands of even more people (and by necessity more or less out of control of the nation states). A commercial airliner took down WTC, a starship would be an WMD capable of taking out a city (or more). One implication of this is that there's a chance that we've already invented practical fusion power, but if it's trivial to miniaturize AND weaponize then people in control of it have decided to withhold it to avoid every weird terrorist group creating one.
- scotty79 3y agoMaybe all roads to space travel lead through global dystopian panopticon and police state?
- throwuwu 3y agoYou might want to check the physics on your assertion that a starship could take out a city. It’d have to be designed to do so otherwise it would just vaporize as it entered the atmosphere at the velocity you’d need for that kind of impact.
- brazzy 3y agoMy money is on option 2 with the key factor being that complex, intelligent life takes a long time to develop. Our empirical data (of sample size one) indicates that it takes multiple billions of years to go from single celled life to even quite simple multi-celled life. If we got lucky with that, the average could easily be longer than the age of the universe.
- willis936 3y agoThe problem with option 3 is that even a small drop below light speed becomes a large multiplier when looking at galactic and intergalactic distances. Let's say you can manage 0.5 c (pushing far beyond any current physical understanding of what is possible), that means we would have up to a 40,000 year heads up on an approaching galactic civilization. Even if it was 0.9c we would have up to 8,000 years notice. Even with something crazy like direct antimatter - matter conversion the amount of energy to bring a ship to that kind of speed would be a gigantic beacon in the night sky. Barring science fiction we can be relatively confident none are on their way right now.
- pfdietz 3y agoGiven that the universe is 13.8 billion years old, 40,000 years is nothing. The presumption that other putative galactic civilizations start at nearly exactly the same time as us is implausible, especially considering more than 9 billion years passed before the solar system even formed.
- willis936 3y agoSure, but we'd see the markers on timescales relevant to us. The gap between the light cone and actual velocity is the critical difference between a kugelblitz and an invasion: you could conceivably conceal the former but not the latter.
- pfdietz 3y agoI'm pointing out that any scenario that requires this synchronization is inherently implausible. So if we don't see the markers, trying to say it's because there are lots of civilizations but they just happened to pop up in synchrony with us is not a plausible theory.
- iraqmtpizza 3y agoAll evidence says that humans stand alone in the galaxy. Everything else is cope.
- LadyCailin 3y agoThat’s like looking only in the drawer, and saying, there is no evidence here that a cat lives in this house. When in fact the cat is just upstairs.
- iraqmtpizza 3y agoThere are electromagnetic waves reaching the earth from this galaxy which were emitted anywhere from 80,000 years ago to an instant ago, and everywhen in between. Practically all alien races among the hundreds of billions of solar systems would have to have been electromagnetically silent for a minimum of 80 thousand years for us not to see them. If you include other galaxies, then they would've had to have been silent since the beginning of time. Also, non-living matter spontaneously forms into living matter by no known mechanism. If you're going to believe something religiously, make it something less trivial than muh aliens.
- throwuwu 3y agoNot silent, just not broadcasting.
- iraqmtpizza 3y ago[flagged]
- throwuwu 3y agoNo, I imagine them doing exactly the same thing we are: using more and more efficient methods of communication as we develop them. Compressing and encoding data, focusing our transmissions where they need to be instead of blasting at max power in all directions, using the most effective form of transmission for the purpose whether it’s laser, microwaves, specific wavelengths of radio, or hard line connections for planet side comms. Signals decay very rapidly over distance so unless you have a very good reason to build a gigantic transmitter capable of reaching beyond a few light years in all directions you’re not going to just accidentally wind up communicating with a random star 100ly away.
- JPLeRouzic 3y ago> 4. Something that we have already noticed is actually evidence of grabby aliens, but it is happening in every direction so we assume that it is a natural phenomenon, because it is so uniform * Brown dwarfs: These are objects with masses too small to ignite nuclear fusion in their cores and shine like stars. However, they are still warm enough to emit infrared radiation. * There are rogue planet candidates that do not belong to a solar system.
- idiotsecant 3y ago5. Grabby aliens do not exist because the universe is a dark forest and any detectable signs of life result in anonymous relativistic snowflake bombardment.