Register a SA Forums Account here!
JOINING THE SA FORUMS WILL REMOVE THIS BIG AD, THE ANNOYING UNDERLINED ADS, AND STUPID INTERSTITIAL ADS!!!

You can: log in, read the tech support FAQ, or request your lost password. This dumb message (and those ads) will appear on every screen until you register! Get rid of this crap by registering your own SA Forums Account and joining roughly 150,000 Goons, for the one-time price of $9.95! We charge money because it costs us money per month for bills, and since we don't believe in showing ads to our users, we try to make the money back through forum registrations.
 
  • Post
  • Reply
I AM GRANDO
Aug 20, 2006

Wafflecopper posted:

I'm sure that must be it, too bad you weren't hanging out with Fermi to tell him it's that simple, we could have avoided this whole conversation.

I would appreciate an earnest answer instead of a dig there. How would we know we were looking at a galaxy-spanning civilization, active or ancient?

Adbot
ADBOT LOVES YOU

Owlofcreamcheese
May 22, 2005
Probation
Can't post for 9 years!
Buglord

Wafflecopper posted:

I'm sure that must be it, too bad you weren't hanging out with Fermi to tell him it's that simple, we could have avoided this whole conversation.

Fermi assumed we would test for aliens a lot more than we ended up doing.

Wafflecopper
Nov 27, 2004

I am a mouth, and I must scream

Antifa Turkeesian posted:

I would appreciate an earnest answer instead of a dig there. How would we know we were looking at a galaxy-spanning civilization, active or ancient?

It's been discussed itt ad nauseum already, pull up Raenir's post history for example. I'm just sick of people coming in with these hot takes like they know better than the scientific community that's been discussing this poo poo for years.

Owlofcreamcheese
May 22, 2005
Probation
Can't post for 9 years!
Buglord

Wafflecopper posted:

It's been discussed itt ad nauseum already, pull up Raenir's post history for example. I'm just sick of people coming in with these hot takes like they know better than the scientific community that's been discussing this poo poo for years.

The scientific alien community? There is very very little funding and very very few scientists studying space aliens (for good reason mostly). But like, even the basic tests proposed haven’t been funded or built.

Name Change
Oct 9, 2005


I'd love to be devoured by the Crawling Chaos as much as the next person but I'm sure scientists, physicists especially, are not amused by people pre-supposing that physics don't matter (and actually none of this matters, now that we think of it!) to aliens.

Like if you're willing to dispense with the limitations of physics and biology and so on, you may as well deal only in superstitious conjecture untethered to meaningful observations.

E: I'm also re-reading posts from last July about people claiming it shouldn't matter if space colonists can't go outside and having a good lol at that given our present condition

Raenir Salazar
Nov 5, 2010

College Slice

Antifa Turkeesian posted:

I would appreciate an earnest answer instead of a dig there. How would we know we were looking at a galaxy-spanning civilization, active or ancient?

I think that's an interesting question and one that I'm not sure who in the thread could answer, I think there's a number between 3 and 5 posters who seem to have legit qualifications for science stuff.

So again, to look at your question: How do we know we are looking at aliens? When do we know we're looking at them? Have we actually been doing a decent job at looking for them?

I think this is an interesting question with a frustrating number of equally probably answers. Is it possible as OCC suggests that we haven't been doing as much testing as we could? On the other hand we do do a *lot* of astronomy, taking pictures at extremely far away places, even gradually over numerous hard drives putting together a picture of a fancy black hole.

If there were solid answers, it wouldn't be a topic for endless discussion.

Other possibilities is that perhaps Fermi may have been discussing stuff, that like Isaac Asimov later on, while very smart and imminently qualified to discuss a number of topics, was he in a position to accurately judge that, gasp, why no aliens? Would he have known what to look for or what signs may exist, and whether we could accurately interpret them? I know he was on the Atomic Bomb Project, but without googling I couldn't tell you if this is a topic he'd be qualified to judge authoritatively. So maybe he was wrong and we haven't had the tools or the will to sufficiently judge whether or not alien life exists based off of observation of outer space alone.


I think though, to give the idea credit again, if the hundreds of millions of years in which we believe life could have come into being and had enough time to reach being a space faring civilization; it isn't just a matter of fundamentally altering the cosmos like primeval gods, but perhaps merely spreading so far and wide that they should have certainly have colonized close enough for there to be various signs, perhaps. If this is true, then the odds are vastly more likely that we would notice something even if we weren't actively looking; ignoring conspiracy theories like Roswell being a sign and governments are suppressing it etc.


I think the most important thing about though about the Fermi Paradox and how it relates to the Great Filter is that even within the limitations of merely our own solar system, I do not think we've found any evidence outside of Earth that life can independently arise. I don't think we've found any bacteria that arose from dead matter (the first candidate for the great filter); no fossils or evidence of multicellular life on Mars, etc.

The important thing is that even if the chance was low, as long as life as we know it has a decent chance of arising often enough, just a once is enough, then they should have had more than enough time.

So the important take away is, if we're the first ones, then the filter is behind is and something about the jumps from dead matter to multicellular life is really really really hard.

BUT, and this is what makes it deeply concerning. If these steps aren't *actually* all that hard, and we found plenty of evidence that life up until the stage of bacteria was actually super easy and common. I.e we find fish in the oceans of Europa or some poo poo like that, then we're probably dead as species because something is going to end us and we don't know what it is yet; because if like can get up until that stage easily enough, then there should probably over a billion years have been enough time for a few dozen civilizations to arise and begin proliferating across millions of stars in that time.

So that's it, that's something much more credible and interesting to focus on, is that even in our own solar system, there's is a startling absence of things. If we find an Earth like exoplanet in Alpha Centauri or something and go there and there's trees and poo poo we're in unfathomable amounts of deep poo poo.

Raenir Salazar fucked around with this message at 06:21 on Apr 15, 2020

Kesper North
Nov 3, 2011

EMERGENCY POWER TO PARTY
can someone here who understands math tell me if stephen wolfram is loving high

https://writings.stephenwolfram.com/2020/04/finally-we-may-have-a-path-to-the-fundamental-theory-of-physics-and-its-beautiful/

this is relevant because it talks a lot about why FTL is impossible for even more reasons than we already thought... but this also makes wild wild loving claims, so I think Wolfram Alpha's calculations landed on 420.

PawParole
Nov 16, 2019

Wafflecopper posted:

I'm sure that must be it, too bad you weren't hanging out with Fermi to tell him it's that simple, we could have avoided this whole conversation.

don’t speak magyar

Libluini
May 18, 2012

I gravitated towards the Greens, eventually even joining the party itself.

The Linke is a party I grudgingly accept exists, but I've learned enough about DDR-history I can't bring myself to trust a party that was once the SED, a party leading the corrupt state apparatus ...
Grimey Drawer

PawParole posted:

don’t speak magyar

I would learn Magyar, just for the chance to see Fermi's face if I tell him people called "Wafflecopper" and "PawParole" are talking about him

Brendan Rodgers
Jun 11, 2014




I always thought the Fermi Paradox when it's discussed today wasn't so much Fermi's "why haven't probes visited us?" but based on a lack of Kardashev scale stellar/galactic engineering when we look out at the observable universe, on the assumption they should be visible, and the following conclusion that no civilisation has reached that level around us.

If you accept the premise that an advanced civilisation would indefinitely expand, and that eventually they would be doing stuff like building Dyson Swarms, cooling their stars down to burn longer, and bringing them closer together, all this should be visible because thermodynamics is a bitch. We can see a lot of galaxies at a lot of stages of development, and there are research projects looking for evidence of such engineering.

Owlofcreamcheese
May 22, 2005
Probation
Can't post for 9 years!
Buglord

Brendan Rodgers posted:

If you accept the premise that an advanced civilisation would indefinitely expand, and that eventually they would be doing stuff like building Dyson Swarms, cooling their stars down to burn longer, and bringing them closer together, all this should be visible because thermodynamics is a bitch. We can see a lot of galaxies at a lot of stages of development, and there are research projects looking for evidence of such engineering.

How would that manifest? We CAN see all sorts of places the stars are in unexpected densities or have the wrong energy level or a billion other anomalies from expectations. But how do you turn that into alien research?

Like how does it go? A million times we have found an endless list of times galaxies had the wrong shape or there was missing matter or a star had the wrong energy level or a supernova was inexplicable or a star was an unexplainable temperature. But like, so what? You are never going to have someone say "it's aliens" on that stuff. no one respectable is going to find Boötes void then say "aliens stole the stars" and not be laughed out.

Like you can't look at the sky and see anomolies the just know aliens did it, because we look at the sky and it's all anomolies still because we are still learning.

Brendan Rodgers
Jun 11, 2014




We definitely don't have a complete picture of the sky, or analysis of it, I was just commenting on the nature of the search.

Here's a couple of studies that show the kinda methods used:

https://www.researchgate.net/publication/253507132_A_search_of_the_IRAS_database_for_evidence_of_Dyson_Spheres

https://iopscience.iop.org/article/10.3847/1538-4357/aac386/meta

There was the candidate, Tabby's Star, apologies if I'm just linking a bunch of stuff that was already linked, this is a big thread I ain't read through it all:

https://en.wikipedia.org/wiki/Tabby%27s_Star

Owlofcreamcheese
May 22, 2005
Probation
Can't post for 9 years!
Buglord

Brendan Rodgers posted:

We definitely don't have a complete picture of the sky, or analysis of it, I was just commenting on the nature of the search.

It's specifically though that we are like 500 years from being able to see an anomaly and say "yes, aliens". because we see anomalies all the time. Galaxies are missing mass, there is no antimatter in the universe and too little lithium, our sun is the wrong temperature, there is radio and x-ray sources we don't know what they are, sometimes stars supernova when they shouldn't be able to, the cosmic background radiation aligns too well with the plane of the solar system.

Like we could just say "it's aliens" about any of these, but that would be stupid, but it means that unless an alien showed up on our doorstep saying "I'm an alien" we just aren't at the point we can derive aliens from anomalies. If we looked and saw a million stars that acted like they had dyson swarms around them we'd be a hundred years before we exhausted all the non-crazy possibilities for what was happening. And even then if we had always seen that from the beginning we'd just end up having worked in that systemic error in every model.

I AM GRANDO
Aug 20, 2006

Raenir Salazar posted:


I think the most important thing about though about the Fermi Paradox and how it relates to the Great Filter is that even within the limitations of merely our own solar system, I do not think we've found any evidence outside of Earth that life can independently arise. I don't think we've found any bacteria that arose from dead matter (the first candidate for the great filter); no fossils or evidence of multicellular life on Mars, etc.

But we don’t know conclusively that there aren’t fossils of multicellular life on mars or that it doesn’t have bacteria right now, to say nothing of Titan or all those ice-shell moons. It seems premature to make claims like this for the same reason it seems premature to say there’s no evidence of interstellar civilizations. We can say that it would be unmistakable or not what physics would predict, but there are plenty of aspects of our galaxy that we don’t understand well enough to do more than guess at, like that star with transuranic elements inside of it. And then there’s all the stuff we haven’t seen yet, to which you could respond “but it should be unmistakable based on what we’ve seen already,” but we could just have an unfortunate sample size. Jupiter could have collected a dozen derelict probes, but we just haven’t seen them yet in the course of our exploration.

I guess the fermi paradox just seems like a solution in search of a problem, and maybe the question of alien detection has to wait until we as a species have a firmer grasp on the nature of the universe and what predictions we can make about what undisturbed space ought to look like.

Owlofcreamcheese
May 22, 2005
Probation
Can't post for 9 years!
Buglord

Antifa Turkeesian posted:

But we don’t know conclusively that there aren’t fossils of multicellular life on mars or that it doesn’t have bacteria right now, to say nothing of Titan or all those ice-shell moons. It seems premature to make claims like this for the same reason it seems premature to say there’s no evidence of interstellar civilizations. We can say that it would be unmistakable or not what physics would predict, but there are plenty of aspects of our galaxy that we don’t understand well enough to do more than guess at, like that star with transuranic elements inside of it. And then there’s all the stuff we haven’t seen yet, to which you could respond “but it should be unmistakable based on what we’ve seen already,” but we could just have an unfortunate sample size. Jupiter could have collected a dozen derelict probes, but we just haven’t seen them yet in the course of our exploration.

I guess the fermi paradox just seems like a solution in search of a problem, and maybe the question of alien detection has to wait until we as a species have a firmer grasp on the nature of the universe and what predictions we can make about what undisturbed space ought to look like.

Yeah, everyone talks like we searched and searched and in these closing days found nothing. But like, we actually didn't look yet.

Like actually look up what tests we have actually done for bacteria on mars. It's a really finite number. the results are basically all "we don't know" or "the test broke". There is some idea we could have done some comprehensive study. But the actual state of even the stuff we have done is 'well, one of the big tests exploded, another was inconclusive, we found methane blooms we can't explain but that could be geologic, the test to figure out if it is is a future mission" instead of any sort of closing the book. Like every single rover could have been covered with mars bacteria nonstop and we never actually run tests to even know that. let some sort of final declaration there is not and never was any life on mars. Let alone life on any other planet or moon.

DrSunshine
Mar 23, 2009

Did I just say that out loud~~?!!!
About the Viking lander anomalous Mars biosignature test - I've actually had the pleasure of being company at a dinner party with a NASA planetary scientist who's spent the last like 20 years or so studying Mars! I brought that question up, and he said it probably wasn't life. Apparently the specific reaction taking place can produce methane through reactions with the perchlorate that is abundant in Martian regolith.

EDIT: As an aside - man I love the kind of crazy balls-to-the-wall stuff NASA comes up with sometimes. Dropping an SUV-sized rover onto mars with a goddamn rocket crane, for example. And this: They want to turn an entire crater on the far side of the moon into a radio telescope. Aahahhaha.

DrSunshine fucked around with this message at 14:35 on Apr 15, 2020

Rappaport
Oct 2, 2013

DrSunshine posted:

EDIT: As an aside - man I love the kind of crazy balls-to-the-wall stuff NASA comes up with sometimes. Dropping an SUV-sized rover onto mars with a goddamn rocket crane, for example. And this: They want to turn an entire crater on the far side of the moon into a radio telescope. Aahahhaha.

I don't see what's crazy about a radio telescope. Now, detonating a nuke is a horse of a different colour...

Libluini
May 18, 2012

I gravitated towards the Greens, eventually even joining the party itself.

The Linke is a party I grudgingly accept exists, but I've learned enough about DDR-history I can't bring myself to trust a party that was once the SED, a party leading the corrupt state apparatus ...
Grimey Drawer

Antifa Turkeesian posted:

But we don’t know conclusively that there aren’t fossils of multicellular life on mars or that it doesn’t have bacteria right now, to say nothing of Titan or all those ice-shell moons. It seems premature to make claims like this for the same reason it seems premature to say there’s no evidence of interstellar civilizations. We can say that it would be unmistakable or not what physics would predict, but there are plenty of aspects of our galaxy that we don’t understand well enough to do more than guess at, like that star with transuranic elements inside of it. And then there’s all the stuff we haven’t seen yet, to which you could respond “but it should be unmistakable based on what we’ve seen already,” but we could just have an unfortunate sample size. Jupiter could have collected a dozen derelict probes, but we just haven’t seen them yet in the course of our exploration.

I guess the fermi paradox just seems like a solution in search of a problem, and maybe the question of alien detection has to wait until we as a species have a firmer grasp on the nature of the universe and what predictions we can make about what undisturbed space ought to look like.

The problem with ancient alien civilizations is that we can never be sure if what we're looking at came to be naturally, or if some random alien artists came over 5 million years ago and xeno-formed some random planet into a hellish nightmare, with molten lead raining from the skies.

Without actually traveling there and making some real close experiments, we'd never be able to find out that this one exoplanet was suddenly changed in the past from its boring, Mars-like true self into what we can see today. We just have to assume that by Occam's Razor, the chance for Assholians traveling around to change planets just to spite future civilizations is round about zero.

Or to move stars and whatever other bullshit space aliens with many millions of years of technological development could pull. Move a couple stars around and a zillion years from now, some other species will see some weird galactic orbits and that's it. They'll probably think those orbits (if they can even notice the anomaly in the first place) are just something that happens naturally, just with low probability!

Recently, I stumbled over a theory that argues the answer to the Fermi-Paradox is "tons of alien species, all at least millions of years space traveling, but they are goons who want to make their computers run faster, so they tend to gravitate into the dead, outer regions of space, like the galactic halo". Amazingly creative, but sadly also totally unprovable, even if we send out probes to the halo tomorrow. Space is simply too huge, if those guys are there and don't want to talk to us, then we simply never find them.

Raenir Salazar
Nov 5, 2010

College Slice

Antifa Turkeesian posted:

But we don’t know conclusively that there aren’t fossils of multicellular life on mars or that it doesn’t have bacteria right now, to say nothing of Titan or all those ice-shell moons. It seems premature to make claims like this for the same reason it seems premature to say there’s no evidence of interstellar civilizations. We can say that it would be unmistakable or not what physics would predict, but there are plenty of aspects of our galaxy that we don’t understand well enough to do more than guess at, like that star with transuranic elements inside of it. And then there’s all the stuff we haven’t seen yet, to which you could respond “but it should be unmistakable based on what we’ve seen already,” but we could just have an unfortunate sample size. Jupiter could have collected a dozen derelict probes, but we just haven’t seen them yet in the course of our exploration.

I guess the fermi paradox just seems like a solution in search of a problem, and maybe the question of alien detection has to wait until we as a species have a firmer grasp on the nature of the universe and what predictions we can make about what undisturbed space ought to look like.

We don't know for sure, albeit I think Mars with the rovers and multiple satellites I think it can be said the chances of evidence of life on Mars is low; hence why its important to go out there and look. Because after climate change our next great existential threat is the Great Filter and determining where we are in relation to it.

Owlofcreamcheese
May 22, 2005
Probation
Can't post for 9 years!
Buglord

DrSunshine posted:

About the Viking lander anomalous Mars biosignature test - I've actually had the pleasure of being company at a dinner party with a NASA planetary scientist who's spent the last like 20 years or so studying Mars! I brought that question up, and he said it probably wasn't life. Apparently the specific reaction taking place can produce methane through reactions with the perchlorate that is abundant in Martian regolith.

I think that is it. Any specific anomaly and saying it's aliens is crazy. But if an anomaly was aliens we wouldn't know. Like maybe the layers of the sun are the wrong temperatures because aliens and galaxies spin wrong because aliens and heavy elements were made in the proportion they are by aliens and supernovas happen when aliens make it happen and methane on mars is from aliens and every other mystery of space is aliens, but like, that is a pretty dead end for research. Someone can say that and everyone can go "yeah maybe" and then go back to looking for actual reasons. But it's not like if the actual reason actually was aliens that we'd know until just hundreds of years of research and exhaustion of every single other possible explanation. Because it's probably not aliens for any specific mystery.

I AM GRANDO
Aug 20, 2006

Yeah I don't mean to sound like I'm keeping hope alive by saying that it doesn't seem like we have enough knowledge to know for sure that there don't seem to be other civilizations in the galaxy, but just to say that there's no reason to start coming up with explanations for why the galaxy seems empty of civilizations when we're not at a state of knowledge to really look closely enough to know that it even seems empty. All that great filter theorizing rests on a really weak foundation and we haven't yet determined the truth value of any of its premises to any real degree.

Libluini
May 18, 2012

I gravitated towards the Greens, eventually even joining the party itself.

The Linke is a party I grudgingly accept exists, but I've learned enough about DDR-history I can't bring myself to trust a party that was once the SED, a party leading the corrupt state apparatus ...
Grimey Drawer
The Great Filter is our stupidity. And it's really more of a Tiny Filter, because it's only stopping us.

Ästivation Hypothesis tells it like it is. All those super-powered ancient aliens, sitting in the cold outer void, laughing (very slowly) about how dumb we are. That's the true answer to the Fermi Paradox.

Owlofcreamcheese
May 22, 2005
Probation
Can't post for 9 years!
Buglord

Libluini posted:

The Great Filter is our stupidity. And it's really more of a Tiny Filter, because it's only stopping us.


Humans haven't even actually died yet. All the "but we will" is still edgy predictions.

Libluini
May 18, 2012

I gravitated towards the Greens, eventually even joining the party itself.

The Linke is a party I grudgingly accept exists, but I've learned enough about DDR-history I can't bring myself to trust a party that was once the SED, a party leading the corrupt state apparatus ...
Grimey Drawer

Owlofcreamcheese posted:

Humans haven't even actually died yet. All the "but we will" is still edgy predictions.

I'm a Human and I tell you, we're dead

Ästivation Hypothesis

(no really, google that poo poo, it's amazingly brazen in its predictions)

Yngwie Mangosteen
Aug 23, 2007
I only get results in German can you provide a translated link or a better google search term?


Edit:
Aestivation hypothesis gives English results.

Libluini
May 18, 2012

I gravitated towards the Greens, eventually even joining the party itself.

The Linke is a party I grudgingly accept exists, but I've learned enough about DDR-history I can't bring myself to trust a party that was once the SED, a party leading the corrupt state apparatus ...
Grimey Drawer
Sorry, in my excitement I forgot English doesn't have Umlaute.

lllllllllllllllllll
Feb 28, 2010

Now the scene's lighting is perfect!
Oh no, my original Alienware PC's GPU runs better with additional cooling, better wait a hundred billion years to really max out FPS for the ultimate VR experience.

Raenir Salazar
Nov 5, 2010

College Slice

Antifa Turkeesian posted:

Yeah I don't mean to sound like I'm keeping hope alive by saying that it doesn't seem like we have enough knowledge to know for sure that there don't seem to be other civilizations in the galaxy, but just to say that there's no reason to start coming up with explanations for why the galaxy seems empty of civilizations when we're not at a state of knowledge to really look closely enough to know that it even seems empty. All that great filter theorizing rests on a really weak foundation and we haven't yet determined the truth value of any of its premises to any real degree.

It's not an issue about hope or not, it isn't like the previous FTL discussion where laymen are badgering physics people with elaborate thought experiments to keep any hope at all of a future gay space communist space opera future alive.

It's more like.

Assuming the universe is empty. Because so far evidence suggests its so even if there are innumerable reasons as to why it could appear to be empty; that would be pretty hosed up for us.

Given the time scales involved. There are many other alternatives for either end; but this is the more interesting one and also the most general case going by Occam's Razor.

I tried to explain the Great Filter once to a coworker but we couldn't get past the stage where he insisted aliens have always been visiting us and the government is keeping it a secret.

Precambrian Video Games
Aug 19, 2002



Wafflecopper posted:

It's been discussed itt ad nauseum already, pull up Raenir's post history for example. I'm just sick of people coming in with these hot takes like they know better than the scientific community that's been discussing this poo poo for years.

This is kind of funny because it's hard to argue that SETI is limited by data availability even now and it certainly won't be 5 years from now. More than anything it's limited by a lack of compelling search methodologies and/or predictions for template signals. More funding and effort is going into radio astronomy for detecting reionization and in optical/IR for exoplanet direct imaging/transmission spectroscopy - all of which are incredibly difficult problems that require multi-billion experiments - because they have reasonable expectations for successful detections and/or an interesting null result. Many of these experiments will be useful for SETI (and other serendipitous science) but they're largely not being built primarily for SETI because nobody has a great idea what to look for and how to look for it efficiently.

Libluini
May 18, 2012

I gravitated towards the Greens, eventually even joining the party itself.

The Linke is a party I grudgingly accept exists, but I've learned enough about DDR-history I can't bring myself to trust a party that was once the SED, a party leading the corrupt state apparatus ...
Grimey Drawer

lllllllllllllllllll posted:

Oh no, my original Alienware PC's GPU runs better with additional cooling, better wait a hundred billion years to really max out FPS for the ultimate VR experience.

I see what you did there

Raenir Salazar
Nov 5, 2010

College Slice
Considering a sufficiently advanced civilization could simulate an entire reality using matroshka brains, that *would* be the ultimate FPS experience. Let pet civilizations grown in the simulation get to varying levels of power, like they're an ant farm and then invade with pre-selected templates of "invasion fleets" like you're controlling the Crisis events in Stellaris.

DrSunshine
Mar 23, 2009

Did I just say that out loud~~?!!!
So the poster earlier in the thread made a salient point - or rather question - in asking "Well what would be a reasonable thing to detect that's uncontrovertible alien activity?"

Off the top of my head, maybe:

  • A dyson sphere or swarm. A star that undergoes a noticeable and unexplainable dimming.
  • Very warm, dark things. A dyson sphere would be unmistakable as a large glowing spot in infrared that doesn't emit in other parts of the spectrum
  • A ringworld. With sufficiently good telescopic imaging, it might be possible to spot a ringworld as a kind of dark band in the visible spectrum against a star's light. Wouldn't work for ringworlds orbiting O-side facing us though.
  • A star system accelerating opposite to the orbits of the rest of the stars in the galaxy, or in a direction orthogonal to the plane of the galaxy. Might be a sign of a system propelled by a Shkadov thruster.
  • "Holes" in the galaxy's density caused by an anomalous absence of matter which was mined, harvested, accelerated elsewhere.

That's assuming that at least some civilization extant or deceased attempted large-scale stellar engineering projects. It could be that these projects are just impractical or inefficient, or that not all spacefaring civilizations valued, the way humans seem to, the ever-increasing exploitation of material and energy resources.

I AM GRANDO
Aug 20, 2006

If we cut up Mercury for parts to make a dyson swarm and it failed and fell into the sun after we went extinct, would there be any clues that Mercury had ever been there?

Owlofcreamcheese
May 22, 2005
Probation
Can't post for 9 years!
Buglord

DrSunshine posted:


  • A dyson sphere or swarm. A star that undergoes a noticeable and unexplainable dimming.
  • Very warm, dark things. A dyson sphere would be unmistakable as a large glowing spot in infrared that doesn't emit in other parts of the spectrum
  • A ringworld. With sufficiently good telescopic imaging, it might be possible to spot a ringworld as a kind of dark band in the visible spectrum against a star's light. Wouldn't work for ringworlds orbiting O-side facing us though.
  • A star system accelerating opposite to the orbits of the rest of the stars in the galaxy, or in a direction orthogonal to the plane of the galaxy. Might be a sign of a system propelled by a Shkadov thruster.
  • "Holes" in the galaxy's density caused by an anomalous absence of matter which was mined, harvested, accelerated elsewhere.

I am 100% sure if we detected any of those that it would not and should not be taken as proof of aliens.

Like the bootles void is 330 million light years across, it only contains 60 galaxies in the whole thing and is an empty space covering .3% of the entire known universe. If you wanna write a scifi story saying aliens ate the rest of the galaxies that's rad, but like, no. Science isn't going to come to that sort of conclusion until a thousand years from now when every guess and theory and hypothesis gets ruled out first.

Like there is almost nothing we could see and say "yup, aliens", because there is always going to be a hundred years of "well our theories didn't predict this but it's been detected" first. Like we just get radio signals we don't know where they come from and right now we have about 50 competing theories with like 2 good solid ones, but none of them are seriously suggesting aliens and it'd be so wildly many failures before anyone started to seriously entertain that. As a race exploring space we are still at the 'we don't know how many planets are in our own solar system" territory.

Raenir Salazar
Nov 5, 2010

College Slice

Antifa Turkeesian posted:

If we cut up Mercury for parts to make a dyson swarm and it failed and fell into the sun after we went extinct, would there be any clues that Mercury had ever been there?

One way would be that if 1,000 LY away you detected with accuracy up to 0.000000001% that a star had its gravity being distorted by "something" with sufficient mass, and then traveled to there and found, wtf there's nothing actually there, then that could suggest it, we sort of have a window to how things looked X many years in the past. So if we had the data storage and harvesting abilities to take perfect snapshots of the observable galaxy every year and crossed references the images to what we actually see up close that could give way to some information.

Owlofcreamcheese posted:

I am 100% sure if we detected any of those that it would not and should not be taken as proof of aliens.

We're just shooting the poo poo, and probably no one here could say definitively, but suppose for the sake of the argument the scientific community sees evidence that there's a star that dims/brights as though something massive was orbiting around it and they have no consensus as to whats happening; that could be something although it isn't definitive proof as in a line between any two points on a X/Y plane is always straight.

Dameius
Apr 3, 2006

Raenir Salazar posted:

One way would be that if 1,000 LY away you detected with accuracy up to 0.000000001% that a star had its gravity being distorted by "something" with sufficient mass, and then traveled to there and found, wtf there's nothing actually there, then that could suggest it, we sort of have a window to how things looked X many years in the past. So if we had the data storage and harvesting abilities to take perfect snapshots of the observable galaxy every year and crossed references the images to what we actually see up close that could give way to some information.


We're just shooting the poo poo, and probably no one here could say definitively, but suppose for the sake of the argument the scientific community sees evidence that there's a star that dims/brights as though something massive was orbiting around it and they have no consensus as to whats happening; that could be something although it isn't definitive proof as in a line between any two points on a X/Y plane is always straight.

If they found Voyager and correlated that the system depicted on the gold disc was the system they were looking at when they came here and decoded everything properly they'd come up one planet short.

Raenir Salazar
Nov 5, 2010

College Slice

Dameius posted:

If they found Voyager and correlated that the system depicted on the gold disc was the system they were looking at when they came here and decoded everything properly they'd come up one planet short.

Stop complaining about Pluto already, god damnit enough already lay off of it.

:haw:

I AM GRANDO
Aug 20, 2006

DrSunshine posted:

So the poster earlier in the thread made a salient point - or rather question - in asking "Well what would be a reasonable thing to detect that's uncontrovertible alien activity?"

Off the top of my head, maybe:

  • A dyson sphere or swarm. A star that undergoes a noticeable and unexplainable dimming.
  • Very warm, dark things. A dyson sphere would be unmistakable as a large glowing spot in infrared that doesn't emit in other parts of the spectrum
  • A ringworld. With sufficiently good telescopic imaging, it might be possible to spot a ringworld as a kind of dark band in the visible spectrum against a star's light. Wouldn't work for ringworlds orbiting O-side facing us though.
  • A star system accelerating opposite to the orbits of the rest of the stars in the galaxy, or in a direction orthogonal to the plane of the galaxy. Might be a sign of a system propelled by a Shkadov thruster.
  • "Holes" in the galaxy's density caused by an anomalous absence of matter which was mined, harvested, accelerated elsewhere.

That's assuming that at least some civilization extant or deceased attempted large-scale stellar engineering projects. It could be that these projects are just impractical or inefficient, or that not all spacefaring civilizations valued, the way humans seem to, the ever-increasing exploitation of material and energy resources.

But wouldn’t there be a natural explanation for each of these things that doesn’t involve engineering from a civilization? There are all kinds of hosed-up or weird stars, but the likelier explanation for a lot of these things would involve physics and chemistry. Like, we found what looked like a dyson swarm, but it’s more easily explained by weird dust clouds we haven’t seen before and that explanation is equally good at explaining things.

That’s not to say that a civilization loving around couldn’t be the actual explanation (plenty of plausible explanations turn out to be wrong in favor of weirder ones), but wouldn’t we have to know the nature of the universe a lot better before we could tell the difference?

People like to mock the ptolemaic model of the solar system as naive, but it seemed about as plausible as the copernican one for a while, until better data were available and people understood the universe better.

It just seems like we have to wait a little while to make sense of what we’re seeing, even if it really looks like a bunch of stars have been deliberately placed somewhere by an intelligence, because we can’t exclude other causes yet. It’s worth thinking about and theorizing, though.

DrSunshine
Mar 23, 2009

Did I just say that out loud~~?!!!
Nature seems to abhor going up against entropy, against the thermodynamic "easiest route". So, while I suppose it wouldn't be inconceivable for some kind of unknown stellar process to force a star to accelerate in an unnatural direction, I think it'd be at least a very strong case for a non-natural explanation.

Adbot
ADBOT LOVES YOU

Owlofcreamcheese
May 22, 2005
Probation
Can't post for 9 years!
Buglord

Raenir Salazar posted:

We're just shooting the poo poo, and probably no one here could say definitively, but suppose for the sake of the argument the scientific community sees evidence that there's a star that dims/brights as though something massive was orbiting around it and they have no consensus as to whats happening; that could be something although it isn't definitive proof as in a line between any two points on a X/Y plane is always straight.


we see stars that dim for unexplainable reasons all the time.

https://www.discovermagazine.com/the-sciences/as-betelgeuse-dims-dramatically-astronomers-scratch-their-heads

we never jump to 'aliens" and usually come up with an explanation. or don't and come up with several theories and move on. We would NEVER settle on aliens as the reason for literally like, hundreds of years of failing to find anything like a plausible reason.

  • 1
  • 2
  • 3
  • 4
  • 5
  • Post
  • Reply