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Self-Replicating Probes?

  1. Jul 29, 2005 #1
    Do you guys consider this a possibility? or maybe even probability that we will eventually send out self-replicating probes out into space?
     
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  3. Jul 29, 2005 #2

    ohwilleke

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    It is certainly possible. Indeed, human explorers are basically that, self-replicating probes. But, consider how much goes into building e.g. a unmanned aerial vehicle or an animal. The instruction set alone is huge (think of all the information in the DNA of an intelligent animal) and the complexity of the ecosystem necessary to sustain even a pretty simple animal (say a colony of bees) or alternately, the amount of equipment that goes into the entire economic chain to build a technologically advanced object, is immense. You need to mine raw materials, refine them, make tools and dies, melt metal, machine it, have a factory to make computer chips, etc.

    The notion of a ten kilo probe that self-replicates is pretty implausible. You'd be looking at more like an asteroid size robotic complex with highly diversified parts that could continually repair and refurbish itself with locally obtained resources. Quite frankly, it would probably be cheaper and more fool proof to send out a self-sustaining ecosystem with enough humans to maintain a technological society (ca. 100,000) than to try to make an entirely robotic system.
     
  4. Jul 30, 2005 #3

    Danger

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    While I agree with most of your response, you are making a few assumptions that don't necessarily apply. To start with, a probe doesn't have any particular size or mass limits. Something on the scale of the International Space Station could contain the appropriate facilities. Once the first is built in orbit and sent on its way, the only requirement is that it can gather the proper raw materials without having to enter and leave a significant gravitational field. The asteroid belt would be ideal for that, as well as possibly Pluto/Charon. In other star systems far in the probe's future, some of the same type of bodies can reasonably be expected.
    The first one, for instance, could stop at the belt and start building new ones. The first of the new could move to Pluto and start building more. Every subsequent generation could then be sent off in various directions to hit the nearest stars of interest. And on from there.
    Secondarily, today's manufacturing methods might not still apply. My personal favourite idea, although it might not be workable, would be to breed a strain of metal-bearing bacteria that can be genetically modified to build micro-mechanical devices and computer chips. If not, then sophisticated robotic factories could do it. The first should carry enough isotopes on board to fuel either Brayton-cycle turbine generators or thermionic converters for at least a dozen more. After that, each should be instructed to find more such materials (unlikely) or become completely reliant upon other power sources (fuel cells for instance, since both hydrogen and oxygen are abundant). Power requirements for any particular probe would be almost non-existent during travel, because everything except a stellar-proximity detector of some kind would be shut down. Once a star system is approached, photovoltaic generators could take over until proper operations are established.
    Naturally, nobody should be holding their breath waiting for reports, but it's better than doing nothing and would be a good supplement to a human migration that seems essential to the continuation of our species.
     
  5. Jul 30, 2005 #4

    Chronos

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    What would motivate you to do that [launching self replicating probes] if you don't intend to follow with colonists? It's like throwing money into the ocean hoping it will rain quarters.
     
  6. Jul 30, 2005 #5
    How about mutations?...mutations could easily "mess" a self-replacting probe up and that would be disastrous.

    Chronos, do you think launching self-replicating probes is a good idea? a plausible one?
     
  7. Jul 30, 2005 #6

    Janus

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    Read The Code of the Lifemaker by James P. Hogan. It's a novel based on just that premise.
     
  8. Jul 30, 2005 #7
    Would these self-replicating probes multiply extremely rapidly? or would it be a slow process?

    Janus, do you think this idea is plausible or is it very sci fi-like?
     
  9. Jul 31, 2005 #8

    Danger

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    They're probably inevitable, but multiple redundancy of supervisory systems would minimize them.

    And extremely well written. I grab anything by Hogan that I can get my hands on. There's a sequel called 'The Immortality Option' that carries the idea along.

    Very slow. Just gathering and refining the proper materials would take years, although that would take place in parallel with construction once things are under way. Naturally, construction would increase geometrically with subsequent generations. Unfortunately, the failsafes to minimize mutations would also probably prohibit improvements in the process.
     
    Last edited: Jul 31, 2005
  10. Jul 31, 2005 #9
    So what would be more efficient? a SRP or the starship that ohwilleke proposed?
     
  11. Jul 31, 2005 #10

    Chronos

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    I still must ask, what would be the motivation for building such a device? It would be enormously expensive and virtually impossible to fail safe the design. It would make more sense [and a lot cheaper] to seed candidate exosolar planets with hardy microbes hoping they might evolve into sentients who would repeat the process - which is pretty much ohwilleke's point. There are also ethical issues. Do we have the right to indiscriminately contaminate the universe with our life forms [be they organic or artificial]?
     
  12. Aug 2, 2005 #11
    So Chronos, do you think sending out self-replicating probes is a good idea?
     
  13. Aug 3, 2005 #12

    ohwilleke

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    The issue comes out to one of engineering. As Chronos notes, the only reason to do self-replicating probes is to have colonists follow. The reason to do it, if you did, I imagine, would be that if you could send self-republicating probes to a very large number of systems (millions perhaps), you could greatly reduce the trial and error components of a later human colonization. And, the virtue of using self-replication v. just sending lots of probes, would be to reduce the mass you have to ship across vast space. For a given energy availability, less mass means more speed.

    This would only be worthwhile, however, if you could get the cost of each probe quite low, and the self-replication rates tolerably high.

    A variant might be a hybrid system in which you would send out a "mother probe" which would have a sophisticated core that was not self-replicating, and would have the ability to formulate bulk components in the field. By analogy, rather than sending 100 rockets into space, you'd send 100 mission capsules and assemble the fuel and the metal skin for the rocket on the fly. This would dramatically reduce weight, while requiring the sophistication level of manufacturing to a much lower level -- rather than having to replicate tools and advanced computers, you would just have to use equipment you already have to build relatively crude components. It would also prevent the system from getting out of control or "mutating".
     
  14. Aug 3, 2005 #13

    turbo

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    That might be a handy way to send out a lot of smaller less sophisticated probes. If we can develop propulsion and on-board power systems based on hydrogen fusion, it would be advantageous to base the mother ship in a nearby interstellar hydrogen cloud, so it can gather fuel as efficiently as possible. Since the funding for NASA's Breakthrough Propulsion program was slashed, we may be relying on chemical boosters for a very long time.
     
  15. Aug 3, 2005 #14

    JesseM

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    Well, if the self-replicating probes could return to earth (or wherever humans are living), they could be used for mining a huge amount of material with an initial investment of only one probe (assuming they were in a region where they could find all the necessary materials to self-replicate, including fuel and whatever they use for a power source). If they could build other goods and return them to earth or space colonies, that would be even better.
     
    Last edited: Aug 3, 2005
  16. Aug 3, 2005 #15
    it is vital that when we discuss humans and deep space that we understand the only realistic way to send colonists and crews is as intelligent software that will be transmitted to or stored in the self-replicating hardware systems/networks that we actually launch- either completely synthetic human-level AI or 'uploaded' conversions/copies of living human astronauts will use the hardware as their space-adapted bodies and their equipment- no habitats will be needed

    we will NEVER send fleshy apes to the beyond- unless as some far future sport/game/lark when it might be feasible for a socitey with total control over matter synthesis and limetless energy- but I don't think even that will ever happen becasue by the time we have reached the technological level to do it the concept of mind/body dualism will be seen as primitive as analyzing chicken entrails- no one will associate their selves with whatever biological/mechanical hardware they are running on-

    'Manned Space Explortion" only means man-controlled- not literal fragile apes-in-a-can- which is not just science fiction- but science fantasy
     
    Last edited: Aug 3, 2005
  17. Aug 3, 2005 #16

    ohwilleke

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    I don't agree. Suspended animation, or multi-generational trip of a colony that is basically self-sufficient for hundreds of years, would both be viable alternatives. I agree that I don't see any viable way to make a round trip in the life of a single person who isn't in suspended animation.
     
  18. Aug 3, 2005 #17

    JesseM

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    But the payload mass (and hence the cost in energy) would have to be much larger--an intelligent being that fits on a computer chip (or whatever the future computing medium is) will weigh a lot less than a biological human + life support system.
     
  19. Aug 3, 2005 #18

    ohwilleke

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    It is an issue of speed. You can transmit information via radio waves, such as the content of a computer chip, at a quite low energy cost and the highest possible speed. You can move people and associated stuff much slower.

    But, if you aren't adverse to making a trip in say 10,000 years instead of 100 years, so what?
     
  20. Aug 3, 2005 #19
    Could a Quazar suck up a Black Hole? Also I think a Black Hole is shaped like a funell conected to another funell. This would mean a Quazar is shaped like that too,but this also means that if you went thourgh a Black Hole you would come out the other side. But you would be crushed in the middle. Also isn't true that a Quazar is as powerful as ten billion black holes.
     
  21. Aug 4, 2005 #20

    Danger

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    To start with, a quasar doesn't 'suck up' anything. It's a source of energy, not a sink for it. While quasars were once considered to be the possible outlet end of black holes, the general theory now seems to be that they are in fact the victims thereof; ie. the radiation output of supermassive black holes ingesting galaxies. A quasar is not a small object. It's something like 5-10% the size of a galaxy that would produce the same energy output by stellar processes alone. (Sorry, but I don't have any specific numbers readily available.)
     
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