The imperative of ending SETI Now

[Serafina]

Even if you have RKVs, if your target has habitats that move around on a regular base, you'll miss them. Such a precaution is very easy to take, and it might be done for completely unrelated reasons as well.
Not to mention the possibility of just not detecting every habitat.

[PeZook]

Hitting a target that small would certainly require either the capability for in-flight targetting and course adjustment (thus reducing maximum viable velocity of the missile) or godlike sensor and computer tech to be able to prefectly preditc their movements. Not to mention a 100% perfect knowledge of the target system, including every single comet that could possibly slightly offset the orbit of your target in 132.65 years.

...and then your target fires thrusters because of a systems malfunction and whoops!

[Ariphaos]

PeZook:

[1) Such missiles represent an incredible investment of resources and energy]

Its cheaper then you think.

No it isn't, see my post on the prior page. It is vastly more expensive than you think.

At least from what i read about. While it is true that relativistic rockets require enormous power supplies,

They don't just require enormous supplies of power. They require multi-parsec launching apparatuses in order to vent heat, or else they boil the projectile away. Again, see my calculator.

it is also true that, with increasingly advanced technology, we can power the whole Earth with more efficient means, say with a field of solar cells adding up to barely more than 200-by-200 kilometers, drawn out into a narrow band around the Moon's equator. Self-replicating robots could accomplish this task with only the cost of developing the first twenty or thirty machines. And once we're powering the Earth practically free of charge, why not let the robots keep building panels on the Lunar far side? Add a few self-replicating linear accelerator-building factories, and plug the accelerators into the panels, and you could produce enough anti-hydrogen to launch a starship - or a relativistic kill vehicle - every year. But why stop at the Moon? Have you looked at Mercury lately? ...

If you think anti-hydrogen is a reasonable means of propulsion you are well into soft science fiction again.

Of course, there's the fact that it is possible for a species to be discovered when it already have colonies around its nearby star, with communication at max. So it is very easy actually for any aliens to pinpoint every off planet industrial base and exterminate all of them.

You are pulling this out of your ass. Look up angular resolution limits.

Without soft science fiction of some kind, for one star system to destroy another star system of similar technological prowess is simply impossible.

[3) The galaxy is fucking gigantic and there might be other, far more powerful civilizations watching you go apeshit and try to exterminate everyone around you.]

To the problem of other civilizations seeing what we are doing, a dreadful solution had been already been suggested in the novel "The Killing Star":

The novel's plot isn't worth the shit termites excrete after eating it, even far more so because the name and plot are presented as some sort of feasible possibility on otherwise good websites like Atomic Rocket.

The Killing Star deserves only one sort of mention in any discussion regarding interstellar contact: mockery.

That's right, for good or ill, kill everyone and just kill and kill and kill until there's no one left. Not even a more advance civilization could stop all the missiles.

No. It is completely and utterly wrong, for several reasons.

1) Targeting at ranges past thirty light years is ridiculously difficult. Past a hundred light years, you don't have a prayer of targeting an Earth-sized planet with one shot. Past a thousand, and ISM variations actually have a meaningful impact on your targeting ability. You literally cannot build a telescope big enough to get the resolution you need.
2) In terms of energy and resource efficiency, throwing RKV's is stupid compared to pointing sunshine and happiness at the target.
3) At relativistic velocities, these projectiles do actually generate significant amounts of blackbody radiation. In addition, firing them will be noticed as well, without an even more resource-wasting impact of applying directional cooling. Antimatter reactions also produce a unique - and detectable - neutrino signature - as over half of the rest mass is converted into high-energy neutrinos. Making it longer and thinner is not an option, because the force you are applying acts on the facing area of the projectile. You need to throw slugs.
4) Coming down to the final point: Sunshine and happiness is the perfect defense against relativistic kill vehicles, should some civilization be dumb enough to use them. You know what they are targeting - or rather, what they have a prayer of hitting - and where they are coming from. Point sunlight in that narrow band, and the RKV just boils away. The only way to compensate this is to make the projectile even longer and thinner, which makes it even less resource efficient to launch, or slower (which gives more boiling time).

[SpaceMarine93]

[How are you going to exterminate "all of them"? Launch an RKV per habitat? Good luck, you'll do nothing but generate energy for your missiles. And if you can't get it to .99c, the targets can just, you know, MOVE OUT OF THE WAY.]

Of course, PeZook, if a civilization could easily move a planet to a different orbit, another civilization on the same level and wants them dead could easily accelerate their missile to just about the speed of light. That is assuming of course that they haven't thought of something on the grounds of "Quantum Entanglement delivery system based Anti-Matter bombs"

[SpaceMarine93]

Xeriar, now that I think about it, you are right.

"blackbody radiation. In addition, firing them will be noticed as well, without an even more resource-wasting impact of applying directional cooling. Antimatter reactions also produce a unique - and detectable - neutrino signature - as over half of the rest mass is converted into high-energy neutrinos. "

If a RKV is at around near the speed of light, hypothetically, how much time does a civilization have between detecting said radiation and neutrinos, and be able to deploy countermeasures needed to save themselves? Its like, "crap, CRAP! If we detected neutrinos from that star system, this means a RKV might be on our - " [EPIC EXPLOSION]

[Akhlut]

Xeriar, now that I think about it, you are right.

"blackbody radiation. In addition, firing them will be noticed as well, without an even more resource-wasting impact of applying directional cooling. Antimatter reactions also produce a unique - and detectable - neutrino signature - as over half of the rest mass is converted into high-energy neutrinos. "

If a RKV is at around near the speed of light, hypothetically, how much time does a civilization have between detecting said radiation and neutrinos, and be able to deploy countermeasures needed to save themselves? Its like, "crap, CRAP! If we detected neutrinos from that star system, this means a RKV might be on our - " [EPIC EXPLOSION]

Quote tags, please use them.

Anyway, as Xeriar has already said, you need a very, very, very large apparatus for shooting RKVs. As such, one is going to have to be far enough out for your apparatus to be undetectable to your target. If you can build it a light year out and be undetectable, that gives the target about 3.65 days (or about 87.6 hours) to do something, assuming the RKV is moving at .99c. However, considering your apparatus is already several light years long already, it is going to be easily detectable at that distance. So, let's move it 10 light years back; uh-oh, now your RKV is detected 36 days before it reaches target and your apparatus still might be visible. If you're apparatus is a full 100 lights years out, your target gets a full year of prep time. So, essentially, your apparatus is already apparant before you can fire an RKV and thus the target can prepare before hand, or they have more than adequate time to prepare for your RKV.

[Ariphaos]

[How are you going to exterminate "all of them"? Launch an RKV per habitat? Good luck, you'll do nothing but generate energy for your missiles. And if you can't get it to .99c, the targets can just, you know, MOVE OUT OF THE WAY.]

Of course, PeZook, if a civilization could easily move a planet to a different orbit, another civilization on the same level and wants them dead could easily accelerate their missile to just about the speed of light. That is assuming of course that they haven't thought of something on the grounds of "Quantum Entanglement delivery system based Anti-Matter bombs"

More pulling crap out of your ass.

All shifting orbits needs is a gravitational tug. We might do that just to compensate for solar expansion.

Accelerating stuff to near lightspeed requires solar sails. Those are not subtle.

If a RKV is at around near the speed of light, hypothetically, how much time does a civilization have between detecting said radiation and neutrinos, and be able to deploy countermeasures needed to save themselves? Its like, "crap, CRAP! If we detected neutrinos from that star system, this means a RKV might be on our - " [EPIC EXPLOSION]

It doesn't really matter. In the thread where I worked out the boiling equations, I believe the necessary warning period was on the order of three days, to boil kilometer long slugs. This was based on the idea of having a sensor net instead, which is more reliable - and easier to fill the sky with a few quadrillion observation stations cheaply, giving good coverage out to a range of several light years.

At such ranges anything less than ~.999 of c is too slow (.999999 is even too slow if the civilization is multi-star system spanning and stars it passes get to take pot-shots). An important thing to realize is that the defender knows more about the target, and the path the projectile needs to take to get there, than the attacker does.

Even more important to realize than an attacker who could mount such an attack - building multi-light year rails - could just as easily have build a more effective defensive system.

[Formless]

But there is so many things that could occur in communicating with aliens that a bloodbath - assuming they even have blood - is inevitable.

Please do not abuse the word "inevitable". It makes you look like a cocky ignoramus.

Fact is, all your arguments rely on either analogies to human behavior, or analogies to science fucking fiction. Until we actually meet an alien lifeform, we cannot make statements about what is and is not inevitable in a first contact situation between us and ET.

By the way... please, for the love of god, learn how to use the quote function. Your posts look like they've been moderated by Lady Tevar FFS. Generally, the color red is has a very specific connotation.

Code: Select all

[quote="SpaceMarine93"]Oh yes, there may be a lot of aliens who are batshit insane, and with good reasons.[/quote]

Oh yes, there may be a lot of aliens who are batshit insane, and with good reasons.

Arguments from supposition do not have any weight on whether or not active SETI should be pursued. I could just as easily suppose numerous benevolent possibilities, and those possibilities would have just as much weight in the risk reward analysis as "but they MIGHT be crazy!1!!".

It especially does not outweigh arguments that have actual facts behind them, like the fact that we are so far away from any alien civilization that the best analogy I can come up with would be if you were blubbering about what if some AX MURDERING PEDOPHILE were to come and kill you and you lived on top of Mount Everest (somehow). Therefor, you should not seek out human contact. It makes you look insane.

Got that? We can't afford to wait to be proven wrong.

You are right. We can't afford to be wrong about the LHC. The possibility that a stranglet or black hole will consume the earth is miniscule but WE CAN'T AFFORD TO BE PROVEN WRONG.

Fucking moron. If we accepted this logic about SETI, we might as well give up on doing science as well. Classic Argument from Ignorance-- if you can't show evidence that your fear is justified, just start making shit up instead! That's got to be just as good, right?

[Sarevok]

I dont get the RKV wank given that RKVs are in greater danger of being destroyed by stray atoms or dust particles. Even if they do they make it to your home system all you need is a sufficently spread out gas cloud to destroy them.

[Simon_Jester]

All right, not to jump up and down on SM93 too hard, because I understand how he could come across some descriptions of this problem and overestimate the threat...


Dude, this problem is a lot less serious than you think- launching genocidal attacks over interstellar distances is hard, whereas defending against them is comparatively easy, if we restrict ourselves to plausible technologies that we know can exist in real life.

And if we start hyperventilating in fear over completely unknown technologies that some hypothetical evil aliens might possess, we'll never stop: what if they're psychic and can use clairvoyance to detect our thoughts over interstellar distances? We'd better all start wearing tinfoil hats just in case! But that would be silly.

Sure, it's logical and reasonable to be cautious in dealing with the unknown. But it's unreasonable and almost always counterproductive to assume there is something to fear in an environment where no information is available. The 'protective' measures you take to ensure 'security' against a threat that may or may not exist will be very costly, both in up-front cost and in opportunity cost.

To illustrate the problem, if you follow this road far enough and you wind up turning into the Spathi, who are really impressively paranoid... for no good reason. In many ways their paranoia and cringing cowardice make them more vulnerable, not less, because they're so terrified of what an enemy might do to them that they cannot react effectively to what an enemy will do to them.

Let that be an allegory for you.


Another factor is that even if we accept the notion that it is easy to build genocidal RKVs (which is not self-evident, as Xeriar has shown)... it is also very easy to detect the launch from anywhere but the target- even if the target cannot see the RKV launch (which it probably can, as Xeriar has shown), people standing fifty light years off to one side can see it quite clearly.

This makes it extremely dangerous, and probably very very stupid, to launch RKVs at neighboring civilizations. Because if you do it, everyone else knows. Any other neighbors who were lurking to avoid detection and death-by-RKV will now have every reason to launch their own first strike at you in hopes of neutralizing your ability to exterminate unoffending civilizations like, well. Them.

Plus there is the colossal risk that, should you launch an RKV at an enemy, you will make the tactical error of not getting them all. What if they have RKVs in reserve? Or, hell, space habitats or other planets in their system that can rebuild their civilization? What if civilization on their planet ultimately survives the Chicxulub-scale RKV impact, emerges from their Fallout-style vaults a few decades later, and vows utter murderous revenge on your species?


In an environment like this, it is much safer not to be an axe murderer at all than to be a well-known axe murderer.

[Simon_Jester]

Ghetto Edit:

SM93, this is covered in the very article you quoted; you've been reading selectively and ignoring the bits that didn't fit in with the alarmism, haven't you?

It's okay, this happens to people once in a while, but... try not to hyperventilate, OK?

[Ariphaos]

I dont get the RKV wank given that RKVs are in greater danger of being destroyed by stray atoms or dust particles. Even if they do they make it to your home system all you need is a sufficently spread out gas cloud to destroy them.

Outside of an actual gas cloud, this only occurs at extreme velocities, or when passing near a star (the blueshifted light boils the surface). It does put an effective 'speed limit' on relativistic travel in general, but it's a reasonably high one. Earth is particularly vulnerable being in the 'local bubble'.

Spawning a dense enough gas cloud (a thousand particles per cubic centimeter or so) across a cubic parsec or two can bring said speed limit down to about .8 of c, which takes roughly a solar mass. A sort of aerogelish bubble would probably be more practical, serve as a simple deflection and early warning system.

[madd0ct0r]

I'm sorry but I missed the bit where we have to stop analyzing incoming radio for SETI in case of RKV's

why? or has the discussion moved on?

[PeZook]

People are now pointing out RKVs are impractical.

Even if they weren't, that's a reason to keep SETI and massively expand it, anyway, since it would provide early warning of an incoming missile.

[Sarevok]

I dont get the RKV wank given that RKVs are in greater danger of being destroyed by stray atoms or dust particles. Even if they do they make it to your home system all you need is a sufficently spread out gas cloud to destroy them.

Outside of an actual gas cloud, this only occurs at extreme velocities, or when passing near a star (the blueshifted light boils the surface). It does put an effective 'speed limit' on relativistic travel in general, but it's a reasonably high one. Earth is particularly vulnerable being in the 'local bubble'.

Spawning a dense enough gas cloud (a thousand particles per cubic centimeter or so) across a cubic parsec or two can bring said speed limit down to about .8 of c, which takes roughly a solar mass. A sort of aerogelish bubble would probably be more practical, serve as a simple deflection and early warning system.

I was thinking smaller.

What about a debri cloud or artifical ring system around a planet ? The RKV denotates tens of thousands of kilometers away. You get a very bright flash but the planet is unharmed.

[Darth Hoth]

On an interstellar scale, as far as we know conventional wars of conquest do not make sense. However extermination by kinetic kill vehicle (relativistic or asteroid spam), bioweapon, nanotechnology or more exotic means is quite within the realms of possibility. The primary risk is that a majority of the alien species will have psychology like Darth Hoth; individuals who place no value on the life of creatures not like themselves and who are paranoid enough to want to eliminate any threat, however remote, to their supremacy.

Or, a technocratic-utopianist transhumanist psychology with completely sociopathic and morally bankrupt goals like replacing humanity with a superior species of "super-intelligent" machine life whose cognition is not "riddled with all the fallacies of human thought" and laughing at the poor, primitive "fleshy organics" while they boast about it on their equivalent of message boards.

But, nice to know I made an impression on you.

***

More on topic: It appears that for some reason, RKVs have become the primary bogeyman of the cosmic paranoids. Probably because of Pellegrino's book. However, as has been pointed out, they are not the only potential danger, or even the most realistic one. Some self-replicating large-scale machinery sent by more stealthy means could be another option. Or, infiltration of Earth by some micro-scale mechanism or organism that would work like a more realistic analogue of gray goo.

In The Killing Star, one other danger that was almost as large as the RKVs as such was a radio'd alien computer virus that destroyed most of the surviving human installations. Going by what little I know on the matter (practically, nothing) that would seem the most probable alien danger to me - if nothing else because the costs of transmitting bare information are utterly minuscule next to those of whatever "physical" weapon our potential space alien enemies might opt for.

Not saying that any or all of these are necessarily stuff we should be up in arms about, mind, but Pellegrino planet-killers are hardly the be-all, end-all of hypothetical interstellar warfare.

For that matter, taking my riposte at Starglider more seriously, what is to say that a benevolent alien species might not be equally dangerous to us as a hostile one? What if the species is extremely altruistic, and willing both to risk themselves and to expend ridiculous resources in order to "help" other, more primitive civilisations? Only that "help" in their parlance means exactly to replace us all with robots or something else equally horrific, because their alien sensibilities can think of no better thing than that to do for anyone.

[PeZook]

They still have to force their help on us, which is not really feasible over interstellar distances.

Also, computer viruses? Really? Because they will obviously be able to get the specs of all the computers working in human space to perfectly tailor the virus to Windows 28K

...and then count on people executing radioed code on machines with administratie access.

[Darth Hoth]

They still have to force their help on us, which is not really feasible over interstellar distances.

Perhaps not. Just trying to expand the discussion a little.

Also, computer viruses? Really? Because they will obviously be able to get the specs of all the computers working in human space to perfectly tailor the virus to Windows 28K

...and then count on people executing radioed code on machines with administratie access.

Is there any possibility that enough of our computer infrastructure and programming languages could be reconstructed from what could be gleaned from our radio transmissions?

As I said, I have no idea about this particular stuff. It just appealed to me because unlike the other options, it does not require space opera-esque infrastructure investments.

[PeZook]

Perhaps not. Just trying to expand the discussion a little.

Essentially speaking, the discussion boils down to the same question of the feasibility of interstellar warfare, only with a more difficult goal (forcing people to upload), which requires boots on the ground and starships in the system.

So, same thing. If they're more advanced than us, they win with little trouble. If there is parity, however, they are fucked.

Is there any possibility that enough of our computer infrastructure and programming languages could be reconstructed from what could be gleaned from our radio transmissions?

You'd need knowledge of both hardware and software and the network you are trying to invade. The best way to introduce a virus is to exploit a security vulnerability in the operating system (such as, say allowing code on pendrives to be executed, dumb users etc.).

The problem is of course that even if you got all that somehow, the virus will still take a decade to get where you want it to be, so the target will have gone through generations of operating systems already

[Serafina]

The easiest way to influence another civilization would simply be radioing them, particularly if your goals are benevolent.

If your goals are benevolent, simply send a lot of scientific knowledge to them in a form they can figure out (mathematics are pretty universal). That only takes one powerful transmitter - and if you are afraid that they'll blow themselves up, any sort of material aid would risk the same and forceful help would automatically involve it.

If you want to protect yourself, simply lie about your own defenses or possibly means of retaliation. That will scare off similarly developed civilizations, and you won't get proper defense against far more advanced ones by any other means anyway.

If you are malevolent, you can still send them lot's of misdirection. Hardly the most effective means, but remember - it's cheap. Also, don't try to send them any data on "how to build a machine that will take over your world" - you have no control over the level of scrutiny that will be applied to it, so your trap is unlikely to work and you might just advance the other species.



A benevolent civilization could rather easily advance plenty of others around it. Doing so might actually be a pretty good way to protect yourself as well, since it's an easy way to build up good relations - AND you will probably have a good idea on how advanced your neighbors are if you do so. After all there really shouldn't be any competition for resources, so alliance-building should not be that hard. And last but not least, they'll act as a buffer if some other civilization gets aggressive.

[LaCroix]

I was thinking smaller.

What about a debri cloud or artifical ring system around a planet ? The RKV denotates tens of thousands of kilometers away. You get a very bright flash but the planet is unharmed.

Scoop up the NEOs and put them to good use...

But you need a sphere, a ring is no good protection in a 'full 3D' environment like space...

[Sarevok]

While a computer virus is impossible a "meme" that tricks humans is an amusing possibilities. In our ecstasy over encountering other life we will pretty much believe any signal that is proven to be alien. Imagine the pranks they could play ! They could lead us into goose chases trying to find their supposed "dyson swarms" or make us paranoid and waste our resources turning Sol system into a fortress.

[Ariphaos]

I was thinking smaller.

What about a debri cloud or artifical ring system around a planet ? The RKV denotates tens of thousands of kilometers away. You get a very bright flash but the planet is unharmed.

Because the actual distance when it strikes is going to be reduced by a factor equal to its Lorentz contraction, and you want to take advantage of
1) The strength of the impact slowing it enough, far enough away, that the strike misses, and
2) Plasmification of the projectile and whatever it hit dispersing.

In addition, making Earth effectively several orders of magnitude larger can very easily mean that Earth gets damaged in a scenario where it would have otherwise been safe.

Now, this is different if, say, you want to protect against another star system's sunshine and happiness, where some sort of shielding system could be activated relatively quickly in the event of an attack. But then you don't need it to be that large, and the intensity of the attack isn't going to be much greater than normal sunlight, and of course spread over an area much larger than the surface area of Earth - you want it to be as small as possible - not tens of thousands of kilometers up. In any interstellar warfare scenario, the key advantage the defending system has is the fact that the attacker must be wasting significant amounts of energy in order to do so. The defender should therefore work to maximize that loss.

[Serafina]

Hmm, the latter is actually a pretty good way for a malevolent alien to play havok with it's enemies via radio. Make them paranoid via broadcasting threats, displays of your (supposed) strength and so on. He'll waste a lot of resources by putting up lot's of defenses, potentially ruining his civilization. Or maybe you can trick him into launching RKVs at fake targets - put some transmitters into a starsystem and let him waste energy by shooting them.

But i suppose information warfare (or propaganda and deception) is too modern for a discussion about space warfare!

[SpaceMarine93]

Fucking moron. If we accepted this logic about SETI, we might as well give up on doing science as well. Classic Argument from Ignorance-- if you can't show evidence that your fear is justified, just start making shit up instead! That's got to be just as good, right?

Alright, I got your picture. In the end I am probably just a bit too simplistic concerning this whole issue. I politely accept your rebuke and argument, and everybody else's