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Transmission rate of grey goo across the universe

  1. Aug 7, 2015 #1
    If I imagine an interplanetary fight between two early races (the universe is about 8 billion years old) and one of them invents a super weapon to extinct the other. The weapon is a grey goo weapon, a swarm of billions of machines, each with the ability to bend light around it to cloak itself, each with the ability to convert matter to energy and back again (a star trek replicator) and has very simple programming:
    Code (Text):
    Find Absorbable Matter
    Move to Matter, avoiding obstacles
    Absorb Matter
    If (amountOfMatter > matterNeededForReplication){
    It'd be an effective weapon and unleashed on a planet could overwhelm a population and continue forever. If the robots can fly through space though, it's a big problem. It was designed to seek out even point light sources as potential matter gathering locations, assuming that their enemy would attempt to flee on ships. If they can travel through the stars, they'd be like an unstoppable virus. Given a million years, they'd eat everything in a galaxy, in a billion, they'd eat everything in their entire galactic cluster. Then with nothing left to eat (they can't eat stars) they go dormant. Then billions of years later, another species evolves and tries to make sense of the universe that it sees. It sees stars and does calculations, and realizes that it can't see most of the matter in the universe and calls it dark matter, as they try harder and hard to figure out what it is, they risk awakening a dormant monster.

    I've heard calculations that even without breaking the speed of light, humans could colonize the entire galaxy in only five million years, but I've also heard that'd forever be our limit. Why? Is that an assumption that we simply wouldn't want to make the long journey to nearby satellite galaxies and beyond, or are the distances that much further? Andromeda is only 20 times the diameter of the milky way away from us?
  2. jcsd
  3. Aug 7, 2015 #2


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    You and K. Eric Drexler, huh ? ...Lol

    Writing: Input Wanted... You should be very, very careful here... It could be a really dark matter, if Drexler put

    some ice-nine in your story! ... :olduhh:
  4. Aug 8, 2015 #3
    Does it have good enough engine to combat gravity well of a planet towards which it was dropped?
  5. Aug 8, 2015 #4
    Sure, they eat matter and change it to other types of matter at will, they have plenty of power. It has a space ramjet, that operates on laws of physics well beyond our understanding. They essentially pull the space in front of them, and expand it behind them. They are capable of directly warping space, so gravity is no obstacle to it. It leaves a trail of slightly expanded space behind the spacecraft. This causes the universe as a whole to appear to expand. As they awaken from their billions year slumber, and engines start getting turned on in the trillions of trillions of trillions, the expansion appears to accelerate. We call that mysterious force dark energy.
    Last edited: Aug 8, 2015
  6. Aug 8, 2015 #5
    To what extent are your little bugs programmed to clump together? To what extent are they programmed to repel each other? Normal physics would suggest that they would drift until they fell into the next gravity well that wasn't a star, and then the food-eating contest would be on again? I'm in the "None of us are here to have this discussion" camp.
  7. Aug 8, 2015 #6
    They're a weapon, but also very intelligent. At least as intelligent as humans but without the individuality and sense of self. In large groups they produce a hive mentality, they are essentially a self replicating army, not a dumb weapon. It's used like this: the species approaches a new star system with an alien species on it. They observe it and discover that they don't worship the same gods as the species with the weapon, so they obliterate the planet, they launch their weapon at it and sit and wait to give the order to recall them. In the group, the communicate and coordinate with each other. Even separated by years of travel and communication time, they are smart enough to coordinate a galaxy filled with them.

    One time, they attacked a species that was stronger than it looked. They accidentally encountered a small colony of a much larger empire like them, the war was brutal and lasted a long time, perhaps both of these species had passed the technology singularity and lived thousands of years. As the defensive empire starts to win the war, the conquerers start getting desperate, they hadn't been vulnerable in millions of years. They spread their weapon throughout the galaxy, giving it orders to destroy anything that wasn't them.

    For millions of years, this war raged on, each developing more and more powerful grey goo weapons to produce bigger robotic armies. Eventually' the damage to both sides was so great that their civilizations collapsed. Now there was nobody left to disarm the weapons. The weapons continued the automated war until one side overwhelmed the other. After millions of years of fighting, the galaxy had been essentially purged, no one else had the technology yet to survive in the middle of it. Only the weapons remained, out there, dormant, with billion year old orders to destroy anything it sees.
  8. Aug 8, 2015 #7
    Nanoberserkers....Hmmm, nasty! But I'm missing something here, are these things capable of--for lack of a better term--space flight? STL? FTL? If we're talking FTL then the time spectrum we're talking about is millions of years; maybe only hundreds of thousands of years. Even if left to drift passively in space they still have the ability to expand exponentially.
  9. Aug 8, 2015 #8
    OK, so in this case you have to make a calculation:
    -what's such device delta V
    -how long it would take them after hitting a planet to spread further

    From those assumptions, you could make a reasonable rate of spreading.

    Anyway, such hive don't mutate? No problem of devices failing to communicate and within one group considering each other as enemy? (I mean speed of light puts limit on communication and coordination within any space empire)
  10. Aug 8, 2015 #9
    Yeah I was thinking about that too. Would these things remain static for millions of years, or would they evolve or change in some way? In the same span of time planet Earth has seen everything from single cell organisms to dinosaurs to us.
  11. Aug 9, 2015 #10
    Honestly? Cell in your organism are programmed that in case of noticing some serious mutations they would commit suicide, to protect the organism from cancer. Noticed problems would be also exterminated by immune system... regardless of that...

    Here is even funnier, because AI would be able to redesign itself to fulfil its role better. The "evolution" can happen within a few years.

    So within game we have:
    -light speed which make any far away communication impossible and makes empire collapse
    -robot ability to redesign
    -evolution that prefer the fittest (it doesn't matter whether only on one planet a high tech redesign rebellion start, if it achieve a serious tech edge it would start devouring its weaker goo)
    -huge time scales

    -eternal war
    -AI civilizations appearing and collapsing

    Transmission rate of space settling ships would be then quite high, whoever invents them first would get a short term evolutionary advantage.
  12. Aug 9, 2015 #11
    Yes...I just can't imagine any scenario where we are not around to have this discussion. I'm not really sure what newjerseyrunner has in mind: is this some sort of Science Fictional equivalent of a Conan story? Flash Gordon enters the crypt of deep space and awakes the little nanoberserkers and chaos ensues. The impression I get is that he (or she) is thinking of using this goo as the explanation for Dark Matter. Cool...if any of us are here to appreciate it.
  13. Aug 9, 2015 #12


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    Only the speed of spacecrafts will limit expansion speed.

    I would avoid connections to the actual universe. Grey goo matter would look massively different from the dark matter in our universe, and the expanding space thing just does not make sense. Also, expansion happens mainly at points of low dark matter density, and not at all within galaxies.
  14. Aug 9, 2015 #13
    I should point out that I was only speculating on whether or not newjerseyrunner was planning to use his nanoids as an explanation for dark matter. I don't know what he actually has in mind.
  15. Aug 9, 2015 #14
    Crypt? I don't like this idea, if you have an ability to expand then you expand instead of staying in crypt. That what the fittest goo would do. ;)

    Otherwise, if its really intended not to evolve, then I'd mention in the story some high tech safety mechanism, which prevents any copy error. Intended to protect winner of goo war, from a rogue goo.
  16. Aug 9, 2015 #15
    Exactly. There would be a reason why the goo has stayed static for millions of years.
  17. Aug 10, 2015 #16


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    Sounds a little far fetched, but it could still make an interesting story. How do you intend to handle the second law of thermodynamics?
  18. Aug 11, 2015 #17
    There is that diet of non-solar bodies that keep these little beasts fed. At some point of course all other astral bodies would be gone and they would either completely shut down or would start feeding on each other. I suppose that this state of affairs could be the first sign of real entropy. My problem, that planet Earth would be among those bodies initially devoured, makes concerns of entropy irrelevant as a story item.
  19. Aug 11, 2015 #18
    No, only until they can't see any more food. If it happens to come across a cloud of space dust, it'll eat it, but it won't actively find it unless it's emitting enough radiation to be seen from a great distance, it's also been billions of years since they went quiet. Their AI directs them to travel towards the brightest object it can see, but also weighs the known density of fellow bots so that they all don't end up at the same spot. They also have memories and the ability to chart, so they aren't simply drawn like a moth to a flame. For example, if they came into our solar system, the inner parts of the solar system would be obliterated, but because things are so dim out at the oort cloud, they'd only be able to really eat that if they stumble across it randomly. It'll be programmed to specifically look for fast moving sources of light, as it's origin was a search and destroy weapon. It wasn't designed to clear matter, it was designed to destroy civilizations, most of which live in the inner parts of their solar systems.
  20. Aug 12, 2015 #19
    This really doesn't refute my argument. The only thing that I can see saving our butts is if they showed up so early in the origin of the solar system that the Earth was either not even formed yet or was in the early stages of forming. No point in devouring a molten ball. Also, if said molten ball was in the habitable zone for the folks who created the grey goo they might program the goo to leave it alone. They might want to move in later when the ball cools down.

    To be honest with you, I'm reaching the point where I'm beginning to have (not always productive) thoughts on how I would use this stuff. One thought that occurs to me is that the goo would look something like an ant colony: some of the goo would be specialized fighters; some of the goo would be sensors; some of the goo would be little brains; some of the goo would be the space drive unit. It doesn't seem likely that every mote of this stuff would be generalized like a human being, the components are just too small. Also how smart is smart with these things? Are they aware that their creators are gone? If so what does the goo think about that?
  21. Aug 12, 2015 #20


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    I don't quite understand. Are these machines around every star in every galaxy they can get to? When a new star forms do they seek it out? It is, after all, a point-source of light. How would any species every be able to evolve in any of these galaxies?
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