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Thread: FRBs might power ETI light sails

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    FRBs might power ETI light sails

    https://www.cfa.harvard.edu/news/2017-09
    According to Next Big Future, this implies thousands of K1 civilizations
    http://www.nextbigfuture.com/2017/03...med-solar.html

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    Groan

    It implies no such thing. The A of A-->B here cannot be proved to be either true or false. Therefore the implicit logic statement is meaningless.

    Gentle folk, please; ET is not going to come and show us how to conquer space. We must do it ourselves. There is so much work to do . . .
    Last edited by John Mendenhall; 2017-Mar-16 at 01:24 AM. Reason: typo
    I'm not a hardnosed mainstreamer; I just like the observations, theories, predictions, and results to match.

    "Mainstream isnít a faith system. It is a verified body of work that must be taken into account if you wish to add to that body of work, or if you want to change the conclusions of that body of work." - korjik

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    FRB = Fast Radio Burst. For those who didn't know, like me.
    "I'm planning to live forever. So far, that's working perfectly." Steven Wright

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    The article was accepted in Astrophysical Journal, so it's OK, but it is (by admission) pure speculation. It seems unlikely to me, because FRBs are coming from outside the galaxy in all directions, so it seems unlikely that ETs in different galaxies around the universe have decided to use the same technology.
    As above, so below

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    No implications made at all. Pure speculation. The paper merely says, If FRBs were ET EM-sail propulsion systems Then based on how many we see, and their properties, we calculate there are X number of ET civilizations out there capable of the technology, the ships could be Y big and could go Z fast. The study does not start with an analysis of FRBs and conclude ETs, it starts with the assumption that FRBs are caused by ETs and makes certain conclusions based on that assumption.

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    A substantial portion of fast radio bursts, from a variety of sky directions, exhibit dispersion values which are various multiples of 187.5 cm-3/pc. It's difficult to see how natural radio emissions could produce such consistent values, under these circumstances. A system of radio transmitters with orderly modulation characteristics might appear to have such values of dispersion.

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    Quote Originally Posted by Ross 54 View Post
    A substantial portion of fast radio bursts, from a variety of sky directions, exhibit dispersion values which are various multiples of 187.5 cm-3/pc. It's difficult to see how natural radio emissions could produce such consistent values, under these circumstances. A system of radio transmitters with orderly modulation characteristics might appear to have such values of dispersion.
    Interesting. It also appears that the timing of the FRBs may be related to the terrestrial second, so it does arm that there is some likelihood they come from an artificial source, just like the perytons. And apparently all but one are from one observatory (Parkes). Perhaps (not joking) it is some kind of a viral advertising campaign. Note that 187.5 just happens to be the volume of a quarter bottle of wine in ml...
    As above, so below

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    But a correction: apparently the pattern disappeared in subsequent observations, so the consensus appears to be that they are indeed some extragalactic phenomenon with no specific periodicity.
    As above, so below

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    Certain fast radio bursts from new sources were observed after the ones with multiples of a set dispersion value. I'm not aware of any specific source that first did, then didn't display such multiples. Looking at a list of 20 sources of fast radio bursts, I find that 12 of them occurred at multiples of 187.5 cm-3/pc

    Perytons have been traced to the use of a microwave oven at the observatory. It is not expected that a microwave oven would have the precision timebase required to produce pulses that accurately synchronized themselves with seconds used in true time keeping. The supposed synchronization with these seconds appears to have been mistaken. In any case, a clear distinction is made between perytons and true fast radio bursts.

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    Quote Originally Posted by Ross 54 View Post
    Certain fast radio bursts from new sources were observed after the ones with multiples of a set dispersion value. I'm not aware of any specific source that first did, then didn't display such multiples. Looking at a list of 20 sources of fast radio bursts, I find that 12 of them occurred at multiples of 187.5 cm-3/pc
    I'm not sure what you're trying to argue. The obvious conclusion is that the initial finding of 187.5 cm-3/pc was just a fluke, and that as more data came in the relevance disappeared. I suppose you could argue that in the beginning we just happened to find a group that were connected, and then started finding others that were not connected, but it seems more reasonable to me to figure that they are a class of objects and that if they do not all have that specific spacing of dispersion values, there is nothing to it. Of course, that says nothing about whether they're artificial or not. They could still well be signals or power devices or whatever.
    As above, so below

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    I think it inadvisable to ignore the fact that sources of up to 60 percent of fast radio bursts conform to a highly orderly looking pattern of a few small integer multiples of 187.5 cm-3/pc dispersion. It may be that those that depart from this pattern are an unmodified natural phenomenon. Perhaps those which conform to the pattern are the same phenomenon, after it has been modified by an advanced ET technology. This could serve some unknown purpose, perhaps space vessel propulsion, as has been speculated, perhaps something else entirely.

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    Quote Originally Posted by Ross 54 View Post
    I think it inadvisable to ignore the fact that sources of up to 60 percent of fast radio bursts conform to a highly orderly looking pattern of a few small integer multiples of 187.5 cm-3/pc dispersion. It may be that those that depart from this pattern are an unmodified natural phenomenon. Perhaps those which conform to the pattern are the same phenomenon, after it has been modified by an advanced ET technology. This could serve some unknown purpose, perhaps space vessel propulsion, as has been speculated, perhaps something else entirely.
    Or, it may be a natural phenomenon.
    "I'm planning to live forever. So far, that's working perfectly." Steven Wright

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    That's certainly conceivable, though, in this line of thinking, it would be necessary to assume an unknown process by which a natural phenomenon repeatedly produces a few small integer ( 2,3,4, and 5) multiples of a single value for dispersion, from a variety of sky sources.

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    Quote Originally Posted by Jens View Post
    The article was accepted in Astrophysical Journal, so it's OK, but it is (by admission) pure speculation. It seems unlikely to me, because FRBs are coming from outside the galaxy in all directions, so it seems unlikely that ETs in different galaxies around the universe have decided to use the same technology.
    If FRBs actually are propulsion technology, then it is possible that any advanced civilisation that doesn't use this technology might observe a FRB and copy it. A kind of long distance reverse engineering.

    It seems quite likely that beamed energy propulsion would be the most efficient way of traveling between stars; much more efficient than carrying fuel with you, which has to be accelerated as well. However radio bursts do not strike me as a particularly efficient way of transmitting momentum to spacecraft.

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    Quote Originally Posted by Ross 54 View Post
    That's certainly conceivable, though, in this line of thinking, it would be necessary to assume an unknown process by which a natural phenomenon repeatedly produces a few small integer ( 2,3,4, and 5) multiples of a single value for dispersion, from a variety of sky sources.
    No, we don't have to assume that. It might have been a fluke that seemed statistically relevant with the first samples but then faded with more data.
    As above, so below

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    Nearly all of the fast radio bursts have been from sky sources that do not repeat this behavior. The fact that some sources of fast radio bursts do not match the orderly pattern does not appear to discredit the observations of those that do. It's difficult to see how one group would necessarily have any conclusive bearing on the other.

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    If they can be said to have a purpose, the orderly class of fast radio bursts may have similar characteristics because they are all representative of a single, expansive culture, or a network of cooperating cultures.

    I agree that radio waves have a rather low energy density, compared to laser beams. This seems to increase the likelihood that the (possible) purpose of orderly FRBs is something other than space vessel propulsion.
    Last edited by Ross 54; 2017-Mar-18 at 01:22 AM.

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    Is the distribution of "orderly" FRBs the same as that of "disorderly" ones, IE all over the sky?
    "I'm planning to live forever. So far, that's working perfectly." Steven Wright

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    Thanks for the suggestion, Noclevername. Went over the list of 20 fast radio bursts to which I've been referring. Found that five of eight that come closest to matching multiples of 187.5 cm-3/pc are confined to a quite small portion of the sky. Right Ascension 16 through 20 hours, but only -5 through -20 degrees Declination.A fairly long, but narrow strip. The six FRBs with less rigorous matching to the discussed dispersion value, and those with no apparent connection to it were distributed much more broadly: 3 to 23 hours Right Ascension, by + 3 to - 85 degrees Declination.

    Link to the list, contained in an article on fast radio bursts:

    https://en.wikipedia.org/wiki/Fast_radio_burst
    Last edited by Ross 54; 2017-Mar-18 at 04:13 PM.

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    If I'm not mistaken, these things are believed to be coming from different galaxies, billions of light years away from us, and therefore billions of light years from one another. It is much too soon for any ET race to have expanded that much unless FTL travel is possible. And if FTL travel is possibly they wouldn't need to communicate with light pulses that only travel at c.
    As above, so below

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    Fast radio bursts are conjectured to have sources billions of light years away because the dispersion values found are consistent with such distances. If the delay of some of the radio frequencies of these bursts, relative to others, has another cause, the distance estimates could be far from accurate.

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    We do have a direct localization of one FRB, which tends to indicate a source outside the Galaxy.
    Our observations are inconsistent with the fast radio burst having a Galactic origin or its source being located within a prominent star-forming galaxy. Instead, the source appears to be co-located with a low-luminosity active galactic nucleus or a previously unknown type of extragalactic source.
    Grant Hutchison

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    These days, just about every astrophysics discovery gets tied into (potential) alien life. IMHO, it is the scientific equivalent of click-baiting.

    A star starts flickering in a mysterious way, and the headlines read it could be a Dyson Sphere - aliens!!
    Habitable planets discovered around a nearby star? Aliens might live there!!
    Don't know what's causing those FRB's? Aliens could be powering their FTL ships!!

    Now I understand the mentality. People want to be read, and their publications want people to read them. A headline which says "Could aliens be causing Star ABC to flicker irregularly?" will get much more attention than a headline that says "Could a newly formed proto-planetary disk be causing star ABC to flicker irregularly?"

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    That's interesting, thank you. There still seems ample room for doubt, though. The weak, continuous radio source reportedly has a diameter of ~ 1.7 milli arc sec.. The FRB 121102 was found ~ 100 milli arc sec. away from it. The apparent proximity could be coincidental. At extragalactic distances, a separation of 100 milli arc sec. could apparently amount to several or even many light years.

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    Quote Originally Posted by Ross 54 View Post
    That's interesting, thank you. There still seems ample room for doubt, though. The weak, continuous radio source reportedly has a diameter of ~ 1.7 milli arc sec.. The FRB 121102 was found ~ 100 milli arc sec. away from it. The apparent proximity could be coincidental. At extragalactic distances, a separation of 100 milli arc sec. could apparently amount to several or even many light years.
    In the Nature letter they estimate the chance of a coincidence at 10 to the -5, so it's about one in 100,000 if . It's still possible, of course.
    As above, so below

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    Quote Originally Posted by Jens View Post
    If I'm not mistaken, these things are believed to be coming from different galaxies, billions of light years away from us, and therefore billions of light years from one another. It is much too soon for any ET race to have expanded that much unless FTL travel is possible. And if FTL travel is possibly they wouldn't need to communicate with light pulses that only travel at c.
    It may be that FRB 121102 and some other sources of Fast Radio Bursts are at extragalactic distances, perhaps on the order of a billion or more light years.
    Considering the possibility that FRBs may be artificial in nature, or an artificial modification of a natural phenomenon does not require us to assume that their purpose would be communicative. They might be the detectable effects of some other project, such as astroengineering on a truly immense scale, or something we haven't even imagined.

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    Maybe it's the effect of ETI opening and closing their wormhole networks.
    "I'm planning to live forever. So far, that's working perfectly." Steven Wright

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    Who can say? Holding a wormhole stable enough to use it as a transit corridor could apparently involve a great deal of energy, and the Fast Radio Bursts are certainly very powerful.

    I found it interesting, too, that five of eight of the FRBs with dispersion measurements closest to multiples of the base value discussed happened to occupy only about three percent of the celestial sphere, while others were much more widely scattered.

    No obvious reason that this should be there case with a natural phenomenon. Could be a network of wormhole entrances and exits confined to a region of space, which represent the destinations preferred by a particular civilization.

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    Quote Originally Posted by Ross 54 View Post
    I found it interesting, too, that five of eight of the FRBs with dispersion measurements closest to multiples of the base value discussed happened to occupy only about three percent of the celestial sphere, while others were much more widely scattered.

    No obvious reason that this should be there case with a natural phenomenon.
    I know that all but on FRB was discovered from archived data. Were they looking at data from all over the sky or from a limited area? In the first case it would be very strange. In the second, not so much.
    As above, so below

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    The list of Fast Radio Bursts I've been using has data points from Right Ascension 1 through 23 &1/2 hours and Declination 33 degrees through -85 degrees. Other than the 5 that seem to have orderly dispersion figures and which are confined to a small portion of the sky, the locations seem quite widespread.

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