Poll of the Day > Doesn't the Fermi Paradox mean we should just stop looking?

(+) Yeah! (+)

If you take the worst case scenario, that were not alone, and the only reason nobodys picking up the phone is that by doing so, then they alert their presence to whatever galactic super predator everybodys hiding from.

Do you think there will come a time when we legitimately have to think about shutting down SETI/METI because of the threat of a potential enemy civilisation? Although unlikely, the consequence of this scenario being true could wipe us out. In which case wed be better off staying off the grid and out of sight.

Or is the genie out of the bottle now and its too late so we might as well just keep transmitting?

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FatalAccident posted...

Or is the genie out of the bottle now and its too late so we might as well just keep transmitting?

It's this.

Fortunately, with just over 100 years of radio transmissions, we cast a 100 light year radius, which on a galactic level really isn't a wide range. It's extremely unlikely anything has even heard us.

Something will probably hear us eventually. The reality is that they won't care. The energy needed to get here outweighs any benefit gained. Earth isn't exactly special, resource wise.

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I'm no expert on radio waves but I'm pretty sure we can't really send a transmission very far either unless they're targeted.

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If we really wanted to assure that we eventually got the attention of a passing alien species, all we have to do is launch a rocket with samples of multiple transuranic elements straight into the sun and wait. If anyone looks at a spectrograph of the light from our star and suddenly there's a spike of elements that literally can't happen on their own normally, someone will eventually show up to take a look.

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faramir77 posted...

Fortunately, with just over 100 years of radio transmissions, we cast a 100 light year radius, which on a galactic level really isn't a wide range. It's extremely unlikely anything has even heard us.

Most of it is just extremely weak static by this point (Like .000000000000000001 of a signal). To really send a signal we would need to send out radio waves as strong as a pulsar to even make a dent.

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I thought this was the Drake Paradox... and the Fermi Paradox was A to the n + b to the n = c to the n

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faramir77 posted...

It's this.

Fortunately, with just over 100 years of radio transmissions, we cast a 100 light year radius, which on a galactic level really isn't a wide range. It's extremely unlikely anything has even heard us.

Something will probably hear us eventually. The reality is that they won't care. The energy needed to get here outweighs any benefit gained. Earth isn't exactly special, resource wise.

maybe it would be to some other planet
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https://youtu.be/KNTxq2v3jcM

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Space invasions is a fun idea but there is no signs of life out there anywhere. No fallout planets or wrecked spaceship battles. Just another fairytale way to act like we can come together as a planet to fight a global threat.
Many sharks think humans are the real invaders.

Yellow posted...

I'm no expert on radio waves but I'm pretty sure we can't really send a transmission very far either unless they're targeted.

Basically this. We've always sort of assumed that radio waves propagate forever, so there's essentially a shell of signal growing ever outward from Earth, which will eventually intersect with any other hypothetical culture, so thousands of years from now, there may be aliens watching our WWII newsreels.

But in reality, signal degradation seems to imply that radio signals become almost meaningless past a certain point, so we'd be almost undetectable to anyone who wasn't already on top of us. It's been theorized that even from Alpha Centauri (the closest star at 4 light years, give or take), you wouldn't be able to detect much other than an extremely high-powered, narrow-beamed signal - and even that would be extremely weak. The ultimate extent of possible detection might be no more than 100 light years or so.

Essentially, SETI as we know it is generally a waste of time and resources, because odds are we'll never be able to detect anyone (or introduce ourselves to anyone) unless they're already close enough to be looking for us. We wouldn't even be able to detect people on the other side of the width of our own galactic arm, let alone anyone else in the Milky Way or beyond. It's only real value would be as an early-warning system for aliens who've already found us and are communication with each other, but refuse to make first contact for some reason. And even then, that's assuming they haven't found a way to shield their communications, or that we'd even know what to look for (if they communicate in some way other than radio waves).
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ParanoidObsessive posted...

Essentially, SETI as we know it is generally a waste of time and resources

I wouldn't say so yet - we've mapped about 2% of the sky now at their current maximum range. Once a full mapping is complete we'll safely be able to say there's no radio-capable aliens within radio range.

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The fermi paradox means you should be the extra terrestrial being.

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ParanoidObsessive posted...

And even then, that's assuming they haven't found a way to shield their communications, or that we'd even know what to look for (if they communicate in some way other than radio waves).

In all honesty we're probably doing the equivalent of banging on bongos in a jungle while wifi data is zipping past us with more information then we can we ever fathom.

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yeah even if there were aliens within 100 light years, it's extremely unlikely they'd actually pick up anything at all. the signal is too weak and spread out now

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papercup posted...

yeah even if there were aliens within 100 light years, it's extremely unlikely they'd actually pick up anything at all. the signal is too weak and spread out now

I honestly wonder how much the heliopause doesn't attune down to pure noise, same with anything that makes it out when it crosses into another system's heliopause.

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Currently confirmed technology to exist or likely be able to exist in the future is such that interstellar war is unrealistic.

This only will change if some more sci-fi level tech becomes available. Most notably, a combination of both a highly effective power source, and a proper high speed warp drive.

As for heliopause, it doesn't affect things TOO badly as we can still receive strong repeating pulses quite fine (i.e. from pulsars, even those in another galaxy). Our furthest detected pulsar is about 50 million lightyears away, but it goes without saying that a pulsar is generally a bit stronger than a pulse of EM waves created by a civilization towards a specific star system to potentially make contact (the pulsar in question is the farthest one we've seen so far too). But its not stronger by enough that you couldn't detect something from at least a few thousand lightyears with good reliability, made by civilization.

The real issue is really just more this:
-If you are capable of FTL travel, then you are going to be using FTL technology for interstellar communication since its faster (even if it means just having ships with cargo crates full of alien USB and SSD equivalents being shipped back and forth between systems), and as such will generally not have your primary communication systems looking for radio waves.
-As such, you will likely not have anything really listening for the radio waves of humans aside from your OWN astronomers, and any SETI-like program YOU have on one or more of your worlds.
-Therefore, aliens who have FTL capability may not really be listening much, aside from some astronomers here and there.

This also means that, well... If you are an alien who DOESN'T have FTL capability, then... There is no reason to go on over to some other planet dozens or hundreds of lightyears away to try and invade them.

All of this of course also all assumes that there aren't aliens out there who both have FTL and at least enough similarity to us that they may or may not have put together some form of reasonably good empire/federation/something similar, which has something akin to a prime directive of just leaving humans alone until they advance enough to properly join/be assimilated/otherwise start interacting with the interstellar community. It tends to amuse me that in most sci-fi settings, the aliens rarely if ever make something similar to Star Trek's Federation. Mass Effect kinda did it, but in most settings its the Humans who end up doing this or starting it.
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Sephiroth C Ryu posted...

There is no reason to go on over to some other planet dozens or hundreds of lightyears away to try and invade them.

I've always had a major problem with this idea overall. There is literally no natural resource on Earth except for life that isn't exponentially more readily available from lifeless rocks and gas balls elsewhere. The idea of invading Earth for it's resources is absurd when there's a billion times more of whatever it is your alien race needs just floating in the Oort cloud. If you've figured out how to cross the interstellar voids on any reasonable time scale, surely you've also sussed that out.

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WhiskeyDisk posted...

There is literally no natural resource on Earth except for life that isn't exponentially more readily available from lifeless rocks and gas balls elsewhere.

Real estate.

Sure, you can strip mine a comet or asteroid for mineral resources, but if you want a hundred acres to build your retirement home on because you're from an overcrowded homeworld and looking to spread out, the easiest way to do so is find a compatible planet and kill off the inhabitants so you can move into their niche.

It's generally one of the first places the human mind goes because it's literally what WE'VE done for most of human history, and what we'd almost certainly do if we start exploring the universe and find a perfect Earth-like world that is inconveniently already inhabited. Sure, we're probably not going to be giving smallpox blankets to aliens, but trying to stake out large chunks of their planet and squeezing them into ever-smaller "native zones" is pretty easy to justify over a long enough time period even with our newly "enlightened" culture.

Especially if the aliens look ugly. Or can't effectively communicate with us in any meaningful way (making it easier to see them more as monsters/animals than individuals).
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We are doing a great job of ruining our world's real estate though. The most aggregious instances of humanity doing real estate invasions was the new world, where populations were sparse and nature (and resources) were pretty close to untouched.

If FTL is easy enough, its easier to just find a planet not inhabited by a civilization at that particular moment in its history and claim/fight over THAT planet instead. Instead of this planet that has been half-ruined by its inhabitants, who are somewhat liable to start spreading radioactive waste around parts of it to boot it in a highly explosive manners if you try and invade them and their other weapons don't prove effective on you. Bear in mind, of course, that many sci-fi movies about invasions give aliens a very major technology that renders us all but unable to harm them, such as powerful energy shields and/or ludicrously durable alloys (strangely, giving them non-shield-based point defense is not too common in sci-fi Modern Earth invasion scenarios, but then again, that would let you hurt them with just spamming a bunch of artillary cannons and railguns at them so shields are more menacing).
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Sephiroth C Ryu posted...

We are doing a great job of ruining our world's real estate though. The most aggregious instances of humanity doing real estate invasions was the new world, where populations were sparse and nature (and resources) were pretty close to untouched.

If FTL is easy enough, its easier to just find a planet not inhabited by a civilization at that particular moment in its history and claim/fight over THAT planet instead. Instead of this planet that has been half-ruined by its inhabitants, who are somewhat liable to start spreading radioactive waste around parts of it to boot it in a highly explosive manners if you try and invade them and their other weapons don't prove effective on you. Bear in mind, of course, that many sci-fi movies about invasions give aliens a very major technology that renders us all but unable to harm them, such as powerful energy shields and/or ludicrously durable alloys (strangely, giving them non-shield-based point defense is not too common in sci-fi Modern Earth invasion scenarios, but then again, that would let you hurt them with just spamming a bunch of artillary cannons and railguns at them so shields are more menacing).
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Which is all utterly absurd when all a potential invader needs to do is show up unannounced with an asteroid the size of Manhattan in tow and chuck it into our gravity well and just hang out in high orbit for a few weeks while the fires burn themselves out if all they want is the real estate.

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That would ruin the estate as well though.
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Sephiroth C Ryu posted...

That would ruin the estate as well though.
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It really wouldn't unless your plan actually involved leaving the actual buildings intact. If for some inexplicable reason, that is your plan all you're going to need is a 60MT neutron bomb detonated at the right altitude over the Earth's North or South magnetic pole which would be trivial tech to a FTL capable species.

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ParanoidObsessive posted...

Sure, you can strip mine a comet or asteroid for mineral resources, but if you want a hundred acres to build your retirement home on because you're from an overcrowded homeworld and looking to spread out, the easiest way to do so is find a compatible planet and kill off the inhabitants so you can move into their niche.

Or like my recent Stellaris campaign. My origin was Doomsday meaning my planet was going to explode in 35-50 years. All the nearby stars didn't have any place I could live. But I found one habitable planet kind of far away but it had intelligent life that was in the Machine Age (think 1920-1944). I quickly invaded them rounded up all the populations and resettled them on a savanna planet I found but had no use for. I mean I probably could've exterminated them all, sold them into slavery on the other side of the galaxy, kept them as slaves, exiled them to other race that would take them, or even turn them into food. But I felt nice giving them a home on a reservation planet.

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Miroku_of_Nite1 posted...

Or like my recent Stellaris campaign. My origin was Doomsday meaning my planet was going to explode in 35-50 years. All the nearby stars didn't have any place I could live. But I found one habitable planet kind of far away but it had intelligent life that was in the Machine Age (think 1920-1944). I quickly invaded them rounded up all the populations and resettled them on a savanna planet I found but had no use for. I mean I probably could've exterminated them all, sold them into slavery on the other side of the galaxy, kept them as slaves, exiled them to other race that would take them, or even turn them into food. But I felt nice giving them a home on a reservation planet.

Trail of space tears.
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WhiskeyDisk posted...

It really wouldn't unless your plan actually involved leaving the actual buildings intact. If for some inexplicable reason, that is your plan all you're going to need is a 60MT neutron bomb detonated at the right altitude over the Earth's North or South magnetic pole which would be trivial tech to a FTL capable species.

If they want Earth specifically, they likely want it because it has a biosphere and an atmosphere they like.

Causing an extinction event enough to wipe out all humanity would also cause, shall we say, a lot of damage to the planet's biosphere, and the atmosphere itself may be rendered less than ideal for a significant time.

Also, that is not how neutron bombs work. If you are referencing the Starburst thing, that requires a fairly large nuke, and further research indicated it isn't as powerful an EMP effect as expected in most cases (even if it was, the EMP would do more damage to buildings and infrastructure then the humans anyway).

If all you want to do is cause human civilization to collapse, then you can use a smaller asteroid (or several) in a manner that causes it to collapse without causing too much harm to the planet (many of the humans would die with the collapse and ensuing chaos, as well as some with the direct effects of the impacts, but humans would still be around with whatever weapons are still left as well as more primitive/post apocalyptic stuff they make).

In short, you can kill a lot of humans easily (likely well over 90%) without hurting the planet you want much. But getting rid of them all is decidedly not easy, as a few can use various resources to survive things that by all rights they normally wouldn't just based on their physical stats.

If the scenario is "we want to get rid of humans to take this planet because we like for its bioshere/atmosphere," then frankly they either have to:

1. Be really patient (like, willing to wait potentially up to a hundred years or more for life to start getting back on track after HOPEFULLY getting rid of the humans in a way that devastated the planet too)
2. Have the necessary resources and tech and equipment available to just cause a stellar "accident" to thin us out and collapse civilization without doing too much damage, then just do a proper invasion and conquer/"rescue" us and get the bulk of the planet in the process.

Past that, you have to look at other scenarios for why an alien race would want to be hostile rather than wanting the planet (which again, would only likely be a thing if they like the same biosphere/atmosphere types we do, as it is pretty easy to find random rocks with or without atmospheres if you don't care what kind of atmosphere it has).
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Revelation34 posted...

Trail of space tears.

Lightyears of tears

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As long as we are thinking up reasons for an invasion/anti-human campaign/attacking earth, though, lets see...

-Something just bad is out there. Like maybe someone with interstellar ability eventually went and got into Hollywood's favorite AI scenario and then lost, leaving an automated AI war machine capable of keeping itself functional and everything, but also lacking any sort of ability to have or gain logical circuitry that emulate empathy (such as even "this stuff is interesting and could prove to teach us something useful, so we should leave it be to see what we can learn from it"). You know, automated, cold, self-maintaining and replicating AI death fleets that don't really make new technology much, if at all. They might not need a reason to attack a planet with life on it, especially if they are effectively just malfunctioning warbots on a galactic scale. They find a weird radio source? They flag it is enemy, and attack.

-They don't want the planet. They actually want humanity in some way. We can imagine various versions of this scenario, from it being a small fleet of slave traders that perform raiding warfare attacking and kidnapping humans to sell, to a civilization that outright just needs the population of earth because it has some issue that it desperately needs humans for. This could be anything from needing a sudden and very large population of slave labor to them just being a dwindling race who wants their civilization to persist even if the last of they themselves eventually die off, and forcefully "recruiting" a new race to continue "holding the torch," and deciding that humanity can/should do it (or that we are just the only ones they found nearby). To other reasons, really. You can imagine lots of things.

-Basically the Zerg or Tyranid, except more realistic. I.e. some sort of alien life who has interstellar technology, but whose general mindset is one of consuming other life like the afforementioned fictional threats, and may potentially even have some degree of hive mind aspect to them. For this scenario, the radio waves don't help, as they would also be looking for planets that show oddities and thus likely have life. So the fact that our planet has an atmosphere with oxygen in it would be the bigger beacon to them than our radio waves. As such, this scenario would tend to require that they are still somewhat a fledgeling interstellar race, as they haven't already found the planet and come to consume it.

-They have idealogical reasons that deem humans as dangerous or something that must be destroyed. They don't care about the planet, and can just lob a big rock at it to clean it out and purge the galaxy of whatever they don't like about humanity. In this scenario, we might not even know the truth behind our incoming demise, as we don't have full tracking of all dangerous objects yet anyway and would assume we just missed it. As for why they don't like humanity, there are plenty of possible reasons, ranging from them learning enough about us to decide we are dangerous in some way, to them just having a xenophobic society to where they just don't WANT other aliens around.

-A more "gentle" reason. They want to induct us into their empire or other such thing. And decide that an invasion or show of force is necessary rather than diplomacy. In this scenario, we could expect anything from a bloody war that doesn't care how many people die as long as the rest surrender, to a civil conflict where they show up and demand some form of surrender, swatting away the military and then leadership until we (or they) put someone in charge who does so.

-They appear hostile but are trying to save Earth's life. They have FTL, but something they DON'T have the technology to stop is going to hit the Earth (like the polar pulse from a star going supernova fairly "nearby" or a reasonably large black hole that will enter the solar system shortly and destroy all the orbits), and they care enough about life to try to forcefully relocate as much of it as possible to another planet that is not about to get sterilized. Maybe they don't have enough time to try and learn enough to be diplomatic, and so they are just doing it forcefully.

These are just a few ideas, mind you. I'm sure there are plenty of other various ideas one can imagine for something to want or "want" to attack earth.
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Sephiroth C Ryu posted...

If they want Earth specifically, they likely want it because it has a biosphere and an atmosphere they like. Causing an extinction event enough to wipe out all humanity would also cause, shall we say, a lot of damage to the planet's biosphere, and the atmosphere itself may be rendered less than ideal for a significant time.

Depends on their culture. Even on Earth, there's a difference between cultures that want immediate results, and ones that are willing to sacrifice in the short-term for long-term gains (ie, "Five Year Plan" scenarios).

A hypothetical alien civilization that tends to plan ahead could potentially decide to fire off a dramatic impact now, and wait for the effects to settle down over the next hundred or so years. Doubly so if they have advanced technological means of their own to help "clean" the environment after the fact to speed up the process.

This can become even more likely if we're talking about a race that has to take the "long way" to get here, where you're talking things like generation ships or decades of cryosleep-style travel. Who would, incidentally, be far more likely to latch on to any habitable planet they find (regardless of whether or not it's already inhabited) because it takes so long to travel to look for one. All you'd need to do is send a smaller strike team here first, have them make your initial strike and sweep for survivors later, so by the time the actual colonization fleet gets here you're already mostly back to normal.

And on that note, for anyone who has free time these days and is looking for something to do, you might want to consider the Worldwar series by Harry Turtledove (In the Balance, Tilting the Balance, Upsetting the Balance, Striking the Balance), which is basically a story with that sort of long-term planning alien race coming to Earth during WWII. And how they might be willing to scorch a bit of earth on the way to conquering their own little piece of it.



Sephiroth C Ryu posted...

Also, that is not how neutron bombs work.

To be fair, if we're talking about an alien race capable of interstellar space flight, they could have access to any amount of technology that we either currently do not possess or outright don't understand. They could theoretically have something akin to that sort of weapon, wherein short-term lethal radiation is released over large swaths that can kill larger organic life without leaving extreme fallout or other consequences that can't be fixed.

Presumably most alien invaders wouldn't necessarily care, though, because they'd have no real interest in preserving structures when they can just bulldoze and rebuild in their own image. So they wouldn't need anything along those lines.



Sephiroth C Ryu posted...

In short, you can kill a lot of humans easily (likely well over 90%) without hurting the planet you want much. But getting rid of them all is decidedly not easy, as a few can use various resources to survive things that by all rights they normally wouldn't just based on their physical stats.

Yes, but to be fair, if you can take out 90% of the species quickly and easily, you've reduced the survivors to scattered bands and isolated individuals who can almost certainly be hunted down and eliminated over time (in fact, you could easily make it a sport for interested individuals - imagine a race of aliens that go out in power armor like Halo and hunt surviving humans like the Predator because they find it fun).

You also start coming up against issues like breeding bottlenecks (if you can't get enough humans in contact in specific areas, they won't be able to breed effectively enough to increase their numbers long-term).

Again, if you have an alien race patient enough to plan in the extreme long-term, they could easily aim for an initial strike that takes out a majority of the population, then follow up with sweeps to reduce the population more and prevent survivors from clustering together into settled regions. Over a century or so you basically reduce the entire population to hunter-gatherers with Stone Age level of tech, which won't be able to put up much more than nuisance resistance once you actually bring your colonizers in to stake their claim.

Again, it's essentially what we did to Native Americans - most of them weren't nomadic hunter-gatherers before Europeans got to the Americas, but massive sweeping plague followed by constant military harrying radically altered their entire lifestyle, and forced them into situations where they effectively couldn't win in the long-term against continuing colonization. Now imagine that scenario, except the Europeans have 21st century planes, tanks, and guns.
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