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Thread: The Fermi Paradox II — Solutions and Ideas

  1. #61
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    Quote Originally Posted by kzb View Post
    The slightly scary fact is, this killer probes theory at least fits with the observations and facts of the matter, which many other theories do not.
    Yes except for why would they do it? Leaving aside the sci-fi rationale, seems a huge waste of resources extinguishing all sentient life in the universe. I´d be more inclined to believe the zoo theory; we are quarantined for some reason with any potential signs of ET blocked from our solar system.

  2. #62
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    "There's no one else out there" fits our observations.

    True

    "They are out there, but too far away to detect" fits our observations

    True on the surface but has a mass of problems. As we've discussed many times on here, the galaxy should be owned by now.

    "They are out there, but too primitive to contact" fits our observations.

    See above. Why would ALL ETs be more primitive than us?

    "There is life out there, but not intelligent life" fits our observations.

    True but many argue that evolving life has a natural arrow towards greater brain power. If that cretaceous asteroid had not hit, the veloceraptors would've colonised our side of the galaxy by now.

    Bear in mind I said fits with the facts, not just fits the observations.

  3. #63
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    The only fact we have is that we have no observations of aliens; both the zoo hypothesis and the non-existence hypothesis fit the that observed fact equally well. So do the hypotheses that ET is vanishly rare, that none has technology, and they are homebodies. I lean towards the hypothesis that ET has found interstellar travel to be impractical.
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    Quote Originally Posted by Noclevername View Post
    So you're assuming FTL is possible?
    Some technique that allows transit and communications at effective, global velocities much greater than that of light may work. This could still preserve the light speed limit, due to relativity theory, in local space.
    If brane theory, or something like it, is correct, it may be possible to leave normal space, enter bulk space, travel through it and re-enter normal space at some other point, having spent less time in getting from point a to point b in normal space than would be possible for light. Time paradoxes are not thought to arise in such a scenario.
    There is also the work of Dr. Harold White of NASA, for the creation of a space warp without the requirement of exotic matter. He's used an electric charge instead. There seems to be a very small reduction in the length of the path traveled by a laser beam through the experiment, when the device intended to warp space is turned on.
    This was duplicated in a second experiment with some technical differences, conducted by another scientist, at another lab. The results are considered inconclusive, mainly because of their smallness, but promising enough to prompt plans for more and better experiments with another sort of interferometer with improved resolution.
    I might add that these experiments have the warp generator turned on and off at a very low rate (0.66 Hz), and used quite small amounts of power. There are theoretical indications that pulsation of the supposed warp field may increase its efficiency, so faster pulsation definitely seems worth trying.
    It seems natural to suspect that if a relatively low power electrical charge may be creating a very small warp field, that a more powerful one might produce a larger warp.

    Link to Wikipedia article-- White-Juday warp field interferometer-- does not seem to be working. Checked address repeatedly. I know an article with this title exists there. Anyone wishing to follow up on this topic may go to wikipedia and request this title.
    Last edited by Ross 54; 2015-Dec-23 at 07:50 PM.

  5. #65
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    Quote Originally Posted by kzb View Post
    "They are out there, but too far away to detect" fits our observations

    True on the surface but has a mass of problems. As we've discussed many times on here, the galaxy should be owned by now.
    Assuming that they are in our own galaxy, assuming that they are old enough, assuming that they spread like weeds for their entire existence, assuming they occupy every star. If all these conditions were fulfilled, then they might logically "own the galaxy". If any one of them is not true, they wouldn't.

    And there's no "should" in observation; we either see it or we don't.

    "
    They are out there, but too primitive to contact" fits our observations.

    See above. Why would ALL ETs be more primitive than us?
    Why would we be more primitive than them?


    "There is life out there, but not intelligent life" fits our observations.

    True but many argue that evolving life has a natural arrow towards greater brain power.
    Among certain strains of higher Earth lifeforms, yes. But I haven't notices sponges or tulips getting any smarter. Only one small branch of our own tree has led to that, and only in very recent biological history.

    If that cretaceous asteroid had not hit, the veloceraptors would've colonised our side of the galaxy by now.
    If velociraptors had developed intelligent complex tool use, which is a big, big if. They showed no sign of developing such a thing when they were alive.

    Bear in mind I said fits with the facts, not just fits the observations.
    An assumption is not a fact. It is a premise. The only fact is that we have no evidence of alien civilizations, or indeed of any extraterrestrial life.
    "I'm planning to live forever. So far, that's working perfectly." Steven Wright

  6. #66
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    Quote Originally Posted by Ross 54 View Post
    Some technique that allows transit and communications at effective, global velocities much greater than that of light may work. This could still preserve the light speed limit, due to relativity theory, in local space.
    If brane theory, or something like it, is correct, it may be possible to leave normal space, enter bulk space, travel through it and re-enter normal space at some other point, having spent less time in getting from point a to point b in normal space than would be possible for light. Time paradoxes are not thought to arise in such a scenario.
    There is also the work of Dr. Harold White of NASA, for the creation of a space warp without the requirement of exotic matter. He's used an electric charge instead. There seems to be a very small reduction in the length of the path traveled by a laser beam through the experiment, when the device intended to warp space is turned on.
    This was duplicated in a second experiment with some technical differences, conducted by another scientist, at another lab. The results are considered inconclusive, mainly because of their smallness, but promising enough to prompt plans for more and better experiments with another sort of interferometer with improved resolution.
    I might add that these experiments have the warp generator turned on and off at a very low rate (0.66 Hz), and used quite small amounts of power. There are theoretical indications that pulsation of the supposed warp field may increase its efficiency, so faster pulsation definitely seems worth trying.
    It seems natural to suspect that if a low power electrical charge may be creating a very small warp field, that a more powerful one might produce a larger warp.

    https://en.wikipedia.org/wiki/White-...interferometer
    Brane hypothesis is not currently supported by any physical evidence.

    Warping space does not necessarily imply FTL, there are certain problems with an FTL warp drive that are predicted by physicists, such as matter being unable to survive inside the warp bubble, and the energy required being much more than we can generate. A sublight warp bubble would still be a major game changer, but its existence currently rests on questionable test results.

    Mind you, I'd love to be wrong! If FTL is proven to exist I'll throw a party. But right now the evidence says no.
    "I'm planning to live forever. So far, that's working perfectly." Steven Wright

  7. #67
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    " If anyone is out there, they're simply too far away to travel or care ."

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    Quote Originally Posted by Noclevername View Post
    Why would we be more primitive than them?
    I think this is a theme that has prevailed primarily due to our perception of intelligent ET. We often associate aliens with space travel, UFOs, and what have you--all of which constitute sophisticated technology. Therefore, the notion goes that we're the primitive ones, trying our best to reach new heights. This is also readily apparent in all kinds of sci-fi media.

    It's purely a philosophical issue.
    “Of all the sciences cultivated by mankind, Astronomy is acknowledged to be, and undoubtedly is, the most sublime, the most interesting, and the most useful. For, by knowledge derived from this science, not only the bulk of the Earth is discovered, but our very faculties are enlarged with the grandeur of the ideas it conveys, our minds exalted above their low contracted prejudices.” - James Ferguson

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    Quote Originally Posted by danscope View Post
    " If anyone is out there, they're simply too far away to travel or care ."
    Probably the most defensible choice.
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  10. #70
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    Quote Originally Posted by Noclevername View Post
    Brane hypothesis is not currently supported by any physical evidence.

    Warping space does not necessarily imply FTL, there are certain problems with an FTL warp drive that are predicted by physicists, such as matter being unable to survive inside the warp bubble, and the energy required being much more than we can generate. A sublight warp bubble would still be a major game changer, but its existence currently rests on questionable test results.

    Mind you, I'd love to be wrong! If FTL is proven to exist I'll throw a party. But right now the evidence says no.
    The answer to the question of whether or not matter can survive inside a space-warping field appears to be approximately as uncertain as the existence of four dimensional branes on the surface of higher dimensional bulk space.
    Dr. White has already discerned ways, in theory, of markedly reducing the energy required to create a space warp. He changed the shape of the warp-creating device from Alcubiere's flattish belt, to a torus. He also noted that on-off pulsations of the warp field should make space more susceptible to warping. If this much has already been done with simple variations in shape and frequency, it seems reasonable that further progress in energy efficiency might be possible.
    Dr. White says that an electrical charge can act as a proxy for exotic matter/energy in his experiment. One reads of the modest power and voltages employed so far, and wonders what might be accomplished if both were increased substantially.

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    One thing to be really careful about with Harold White's work is that we are talking about science through blog entries. None of this has been peer-reviewed. They are essentially rumors, even if the work is being done at NASA.
    As above, so below

  12. #72
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    Dr. White's paper-- Warp Field Mechanics 101, has been published by the Journal of the British Interplanetary Society, which is reportedly a peer-reviewed journal. This paper covers the history of scientific work on the space warp field, from Alcubierre, forward. White's contributions to warp field theory are discussed. It also contains a description of Dr. White's experiments, under the auspices of NASA.
    Last edited by Ross 54; 2015-Dec-23 at 11:27 PM.

  13. #73
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    Quote Originally Posted by Ross 54 View Post
    Dr. White's paper-- Warp Field Mechanics 101, has been published by the Journal of the British Interplanetary Society, which is reportedly a peer-reviewed journal. This paper covers the history of scientific work on the space warp field, from Alcubierre, forward. White's contributions to warp field theory are discussed. It also contains a description of Dr. White's experiments, under the auspices of NASA.
    Thanks for the link, and I'll read through it. However, just to put it in proper perspective, from the abstract it is clear that it is just an outline of the idea and doesn't contain any evidence or results of experiments.
    As above, so below

  14. #74
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    Since Dr. White's experiments have had suggestive but not conclusive results, the time for a peer-reviewed paper covering the experimental results may still lie in the future. I was under the impression that Alcubierre had made a good theoretical case for a warp field, and that Dr. White had done the same for his own, more energy-efficient version of it.

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    Even if there were some new physics that permitted FTL travel or communication, would this not still be subject to reverse time causality inherent in space time?

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    Quote Originally Posted by Ross 54 View Post
    Since Dr. White's experiments have had suggestive but not conclusive results, the time for a peer-reviewed paper covering the experimental results may still lie in the future. I was under the impression that Alcubierre had made a good theoretical case for a warp field, and that Dr. White had done the same for his own, more energy-efficient version of it.
    I'm not sure if this is really the right place to discuss this, because it inevitably comes up in these types of discussions. I think it's more than just there not being any conclusive results yet. Peer-reviewed papers are published all the time that have tentative results, so I don't think that's really the issue. I think it's more like this: in general the physics community is skeptical that this kind of thing is possible at all. The idea rests on the idea that you can create negative pressure, and my impression is that the mainstream view is not that "dark energy" creates negative pressure, but rather that it is an intrinsic property of space to expand and that the expansion is halted by mass. And I looked at the interferometer setup and in a sense it makes sense, but all it is doing (I think) is measuring differences in the speed of light, so whether it is measuring a negative pressure or rather a positive pressure, I don't know how they can tell. Maybe somebody more knowledgeable can answer. I think that basically NASA has decided to allocate some small amount of funding (I think it is a good idea, personally) to wild ideas that probably have no validity but who knows.
    As above, so below

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    Quote Originally Posted by agingjb View Post
    Even if there were some new physics that permitted FTL travel or communication, would this not still be subject to reverse time causality inherent in space time?
    Not necessarily, at least in some interpretations involving 'short cuts' through bulk space, judging by what I've read.

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    Quote Originally Posted by Jens View Post
    I'm not sure if this is really the right place to discuss this, because it inevitably comes up in these types of discussions. I think it's more than just there not being any conclusive results yet. Peer-reviewed papers are published all the time that have tentative results, so I don't think that's really the issue. I think it's more like this: in general the physics community is skeptical that this kind of thing is possible at all. The idea rests on the idea that you can create negative pressure, and my impression is that the mainstream view is not that "dark energy" creates negative pressure, but rather that it is an intrinsic property of space to expand and that the expansion is halted by mass. And I looked at the interferometer setup and in a sense it makes sense, but all it is doing (I think) is measuring differences in the speed of light, so whether it is measuring a negative pressure or rather a positive pressure, I don't know how they can tell. Maybe somebody more knowledgeable can answer. I think that basically NASA has decided to allocate some small amount of funding (I think it is a good idea, personally) to wild ideas that probably have no validity but who knows.
    Maybe nothing will, or can come of Dr. White's work. Then again, maybe he's onto something that very few others can see. There have been a number of instances in the history of science, where the mass of opinion was wrong and the outsider was right.

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    Quote Originally Posted by Ross 54 View Post
    Maybe nothing will, or can come of Dr. White's work. Then again, maybe he's onto something that very few others can see. There have been a number of instances in the history of science, where the mass of opinion was wrong and the outsider was right.
    Yes, which is why I think that NASA is justified in providing some funding. So sure, the possibility is there. But I wouldn't get my hopes up too high.
    As above, so below

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    Quote Originally Posted by Ross 54 View Post
    Not necessarily, at least in some interpretations involving 'short cuts' through bulk space, judging by what I've read.
    It's not the interpretation, it is the configuration. FTL always leads to time displacement in certain frames of reference; the only way to protect yourself for certain against reversal of causality is to ensure that you jump to a location well outside your own light cone. This could allow long-distance communication at faster-than-light speeds; but when you get closer you can get into trouble.

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    Quote Originally Posted by danscope View Post
    " If anyone is out there, they're simply too far away to travel or care ."
    I don't think you have some critical pieces of evidence showing up because of JANAP 146. Might never see them. pete

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    Hi Trinitree , I'll brush up on JANAP 146 . Your recommendation carries a lot of respect round these parts.
    And a great Happy Holiday to you, Sir.
    Best regards,
    Dan

  23. #83
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    Hi again, Yes, they do have their ways with information We always wonder if there has been anything in the " Real sense of things."

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    Quote Originally Posted by agingjb View Post
    Even if there were some new physics that permitted FTL travel or communication, would this not still be subject to reverse time causality inherent in space time?
    If there is a physically realized FTL system (Alcubierre's space warp and Krasnikov's tunnel are mathematically possible but do not seem physically realizable), then the problems with causality will be sorted out. Philosophically, I don't think that retaining causality is a valid reason for claiming FTL is not possible*, as I view causality to be a result of physical law, but not, of itself, one.



    ---------------------------

    * As an aside, I don't think FTL is physically realizable. GR may have solutions that allow things like Alcubierre bubbles, but those solutions also require exotic matter.
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  25. #85
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    I suppose I'm happy to accept, in principle, that FTL may be possible, with any implications for causality. I'd just love to see the description of the world in which those implications are resolved.

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    Quote Originally Posted by agingjb View Post
    I suppose I'm happy to accept, in principle, that FTL may be possible, with any implications for causality. I'd just love to see the description of the world in which those implications are resolved.
    Lots of time travel stories out there. How damaged causality would become in an FTL universe is, I suspect, dependent on the nature of the FTL: at one extreme, if one FTL termini need to be inside of super-massive black holes and only small amounts of mass (less than a few million kilograms) can be transferred during either SMB's lifetime, nothing would happen to causality; similarly, an FTL which requires one terminus to be outside the observable universe would similarly seem to have no effect on causality.
    Information about American English usage here and here. Floating point issues? Please read this before posting.

    How do things fly? This explains it all.

    Actually they can't: "Heavier-than-air flying machines are impossible." - Lord Kelvin, president, Royal Society, 1895.



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    It was my impression that the severe causality disruptions really build up with three mutually communicating points. But I will admit that I don't really know enough to be more than sceptical about FTL effects.

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    A concrete example of a possible causality violation to try to understand this: A trip in space at a velocity globally well above that of light, but not infinite. Some amount of time passes in starting at point A and reaching point B. The same is true for the return trip. So, one can not return to point A earlier in time than when the first left it, can they? If bulk space, a warp bubble, or some domain not connected to normal space has no frame of reference, with respect to normal space, paradoxes apparently can not occur, as these are considered to require the clashing of two different frames of reference, are they not?
    Last edited by Ross 54; 2015-Dec-31 at 08:58 PM.

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    Quote Originally Posted by Ross 54 View Post
    If bulk space, a warp bubble, or some domain not connected to normal space has no frame of reference, with respect to normal space, paradoxes apparently can not occur, as these are considered to require the clashing of two different frames of reference, are they not?
    You can do what you like if you don't connect to the real universe, but once you do causality reversals become possible. If you use a warp bubble to communicate at faster-than-light speeds it can be used to transmit information into the past of other observers, even if an observer inside the bubble experiences no time dilation at all. Sending information into the past is spoilers.

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    " yeah... give me $50 on " Hot Shot " in the third race to win . "

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