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Thread: FRBs might power ETI light sails

  1. #31
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    Quote Originally Posted by Ross 54 View Post
    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.
    And those "orderly" FRBs were discovered from the same assay as the rest?
    "I'm planning to live forever. So far, that's working perfectly." Steven Wright
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  2. #32
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    One thing that's a bit frustrating (things never move as fast as we want) is that apparently there are thousands of FRBs each day, and yet only 17 have been published. Perhaps as we get more things will become clearer.
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  3. #33
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    Quote Originally Posted by Ross 54 View Post

    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.
    And in fact a civilization that would have existed billions of years ago since it takes billions of years for the light to reach us.
    As above, so below

  4. #34
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    Quote Originally Posted by Noclevername View Post
    And those "orderly" FRBs were discovered from the same assay as the rest?
    Nearly all of the sources of FRBs were reported by Parkes Observatory, in Australia. Of the Eight with DMs reasonably close to multiples of 187.5 cm-3/pc, at least six were seen at Parkes, one at Arecibo Observatory, in Puerto Rico, and one, from a not-yet-ascertained observatory.

    The figures for the eight 'orderly' FRBs, in terms of multiples of the base figure discussed, are given below. Asterisks note those found in the highly confined area, RA 15 through 0 hrs., Decl. -5 through -15 degrees:

    FRB 010621 3.97 Parkes *
    FRB 010724 2.00 Parkes
    FRB 110220 5.03 Parkes *
    FRB 120127 2.95 Parkes *
    FRB 121102 2.97 Arecibo
    FRB 130626 5.07 Parkes *
    FRB 140514 3.00 Parkes *
    FRB 110627 2.98 Unid
    Last edited by Ross 54; 2017-Mar-22 at 06:22 PM.

  5. #35
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    Quote Originally Posted by Jens View Post
    One thing that's a bit frustrating (things never move as fast as we want) is that apparently there are thousands of FRBs each day, and yet only 17 have been published. Perhaps as we get more things will become clearer.
    I assume that the expectation of thousands of FRBs each day is based on an astrophysical model of a presumed natural phenomenon.
    It seems worth asking why, if this model is correct, why we've only managed to observe such a tiny fraction of them. There have been numerous radio astronomy surveys, over the years, of large portions of the sky.

  6. #36
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    Quote Originally Posted by Ross 54 View Post
    Nearly all of the sources of FRBs were reported by Parkes Observatory, in Australia. Of the Eight with DMs reasonably close to multiples of 187.5 cm-3/pc, at least six were seen at Parkes, one at Arecibo Observatory, in Puerto Rico, and one, from a not-yet-ascertained observatory.

    The figures for the eight 'orderly' FRBs, in terms of multiples of the base figure discussed, are given below. Asterisks note those found in the highly confined area, RA 15 through 0 hrs., Decl. -5 through -15 degrees:

    FRB 010621 3.97 Parkes *
    FRB 010724 2.00 Parkes
    FRB 110220 5.03 Parkes *
    FRB 120127 2.95 Parkes *
    FRB 121102 2.97 Arecibo
    FRB 130626 5.07 Parkes *
    FRB 140514 3.00 Parkes *
    FRB 110627 2.98 Unid
    Thank you. Were these full-sky surveys?
    "I'm planning to live forever. So far, that's working perfectly." Steven Wright
    "It is the duty of the writers to seduce me into suspending my disbelief!" Paul Beardsley

  7. #37
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    Quote Originally Posted by Ross 54 View Post
    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.
    We might just as easily say they could be songs from a swarm of space-going lifeforms... just as much proof.
    "I'm planning to live forever. So far, that's working perfectly." Steven Wright
    "It is the duty of the writers to seduce me into suspending my disbelief!" Paul Beardsley

  8. #38
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    Quote Originally Posted by Noclevername View Post
    Thank you. Were these full-sky surveys?
    Almost all FRBs were found in the Parkes Observatory archives. They could presumably be from any observations made there, not just from whatever sky surveys they engaged in. All FRBs are South of +35 degrees, due largely to Parkes location in Australia, which affords a view of the Southern sky.
    Last edited by Ross 54; 2017-Mar-23 at 11:21 PM.

  9. #39
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    Quote Originally Posted by Ross 54 View Post
    Almost all FRBs were found in the Parkes Observatory archives. They could presumably be from any observations made there, not just from whatever sky surveys they engaged in. All FRBs are South of +35 degrees, due largely to Parkes location in Australia, which affords a view of the Southern sky.
    So it could be an artifact of selection?
    "I'm planning to live forever. So far, that's working perfectly." Steven Wright
    "It is the duty of the writers to seduce me into suspending my disbelief!" Paul Beardsley

  10. #40
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    Quote Originally Posted by Ross 54 View Post
    I assume that the expectation of thousands of FRBs each day is based on an astrophysical model of a presumed natural phenomenon.
    It seems worth asking why, if this model is correct, why we've only managed to observe such a tiny fraction of them. There have been numerous radio astronomy surveys, over the years, of large portions of the sky.
    I think that yes, the idea that there are many is based on the assumption that they are distributed evenly throughout the universe. If we find that they are not, that they only exist in a specific location of the sky, it will be a very interesting finding. But my understanding is that the paucity of findings is just like the paucity of observations of Tabby's star, that it's not so much that we don't have the data but rather that we don't have enough people going through data and writing papers about it. Almost all of the FRB findings so far (I think with the exception of one) have been made by going through old data. So I guess that technically you or I could go through the data and write a paper about another event, but unfortunately I don't have the expertise or the time.
    As above, so below

  11. #41
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    Quote Originally Posted by Noclevername View Post
    So it could be an artifact of selection?
    Given that the entire Southern sky was available, plus nearly 40 percent of the Northern, it doesn't seem that there was a great deal of selection going on.

  12. #42
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    Quote Originally Posted by Ross 54 View Post
    Given that the entire Southern sky was available, plus nearly 40 percent of the Northern, it doesn't seem that there was a great deal of selection going on.
    But you haven't shown that. You said it was only after astronomers went sifting through old data, that the "special" FRBs were discovered. Nothing was said about how they selected their choices to examine, or from where.
    "I'm planning to live forever. So far, that's working perfectly." Steven Wright
    "It is the duty of the writers to seduce me into suspending my disbelief!" Paul Beardsley

  13. #43
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    Quote Originally Posted by Ross 54 View Post
    Given that the entire Southern sky was available, plus nearly 40 percent of the Northern, it doesn't seem that there was a great deal of selection going on.
    You might be right, but I would need to be convinced. It seems that what's happened is that people have gone over data from surveys (so archived data), and they don't necessarily cover the whole area accessible to the telescope. For example, the one FRB that was discovered from Arecibo was from a survey of pulsars that covered an area "low Galactic latitudes (|b|≤5) in the Galactic longitude ranges accessible by the Arecibo telescope (32<l<77) and 168<l<214)." So it's within a certain constrained range of latitudes. And the first one (Lorimer) was discovered during a search of a survey of the Magellanic clouds. So isn't it possible that the "regular" ones are close together because they are taken from data covering a certain part of the sky?
    As above, so below

  14. #44
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    And just making it a bit more complicated, I read a bit and found out that FRB 140514, which was detected in real time, was done during a survey where they aimed the telescope at previously discovered places to look for repeats, and it was very close to the location of FRB 120127, but in that case it's because that's where they were looking.
    As above, so below

  15. #45
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    I have not yet found substantial detailed information on how pulsar survey data was being scrutinized when FRBs were found. It seems possible that this scrutiny was a less than complete examination of the available data, which reportedly covered large portions of the sky.

    At this point, it would probably be more useful to look at other data about FRBs, where any possible 'selection artifact' would not be expected to occur. Besides what has already been mentioned about apparently orderly measurements of dispersion, an additional matter recently came to my attention, which might be of interest.

    The peak signal strength of the FRBs does not appear to be randomly distributed, as one might expect for natural objects of various intrinsic energies, at various distances. The range of values here is 0.22 to ~128 janskys. Approximately 60 percent of FRBs fall with a tiny part of that range, between 0.22 and 0.75 janskys. An even tighter aggregation occurs, with 38 percent of FRBs between 0.4 and 0.5 janskys.
    Last edited by Ross 54; 2017-Mar-24 at 11:35 PM.

  16. #46
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    How does this article fit into the discussion?

    http://www.news.com.au/technology/sc...d06dc7873677ab
    "It's the rabbit hole that matters, not the blackhole, the wormhole or any other hole," the wolf said.
    "But, what's in the hole, Mr. Wolf?", came the question after a long pause.
    "Infinite approximations deciding everything exactly with just enough uncertainty." The wolf howled with some difficulty.
    "What about the rabbit?", was the next question.
    "Oh, he's long gone!", the wolf declared instantly.

  17. #47
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    I think the latest findings may it quite unlikely that it's something artificial, meaning interference from something local (there was a series of FRB-like phenomena that were later determined to have been caused by microwave ovens at the facility (these things are very sensitive!). But since a number of telescopes have found the same type of thing, it seems indeed to be extraterrestrial, so the search goes on for an explanation of what they are.

    By the way, that paper has been discussed in another thread.
    As above, so below

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