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Fraser
2017-Apr-26, 07:10 PM
Here's a big mystery in astronomy: fast radio bursts. Brief shrieks of radio waves coming from space. What are they? Where do they come from? Astronomers have no idea.
The post What Are Fast Radio Bursts? (https://www.universetoday.com/135259/fast-radio-bursts/) appeared first on Universe Today (https://www.universetoday.com).


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Spacedude
2017-Apr-26, 09:59 PM
Now that is weird, extremely strong yet extremely brief bursts without continuity?!

Ross 54
2017-Apr-27, 02:53 PM
It's interesting, too, that about half a dozen of these Fast Radio Bursts have dispersion measurements that are small integer multiples of 187.5 cm to the minus three, over parsec. Hard to see how a natural phenomenon produces that pattern.
Maybe the others follow some other consistent pattern like this, that hasn't been noticed. Or maybe FRBs are a natural phenomenon, which is sometimes modified artificially for some purpose. Maybe spacecraft propulsion, maybe communications, or perhaps something we can't even imagine.
It's never aliens . . . until it's aliens. It stands to reason that if we keep looking for signs of extraterrestrial intelligence, we may find them eventually. Since we don't know how plentiful or how near such civilizations are, we have no way of predicting how long or how short our search will be.

geonuc
2017-Apr-27, 10:29 PM
It's interesting, too, that about half a dozen of these Fast Radio Bursts have dispersion measurements that are small integer multiples of 187.5 cm to the minus three, over parsec. Hard to see how a natural phenomenon produces that pattern.
Couple of questions for you, and these are legitimate questions, not challenges. I am far from expert in this field.

1. Why is it hard to see that a natural phenomenon produced the pattern you suggest?

2. You say six show this pattern yet over two dozen have been detected. Could your pattern be due to random, as yet unknown, variables? Especially since (presumably, correct me if I'm wrong) the multiples you attribute to the pattern are probably not exact but approximate within the limits of error of the detection equipment.

Ross 54
2017-Apr-27, 11:21 PM
I don't know of any natural phenomena that can, or would be expected to, select for D (Dispersion measurement) to match very closely a few small integers - 2,3,4, & 5. Can you suggest any? These occur in objects far apart in the sky, and, so, presumably very distant from one another. Perhaps these are instances of random, unknown variables. It seems perhaps unlikely, though, when the published figures indicate accuracy above 99 percent.

Jens
2017-Apr-28, 01:59 AM
It's interesting, too, that about half a dozen of these Fast Radio Bursts have dispersion measurements that are small integer multiples of 187.5 cm to the minus three, over parsec. Hard to see how a natural phenomenon produces that pattern.


It's hard to see how artificial phenomena separated so far apart could show such a pattern as well. But then again, as we discussed in another thread, the pattern is becoming weaker as new bursts are studied, so the chances now is that the 187.5 was just a fluke in the data. With enough numbers, you are bound to have ones that are multiples of others.

The other possibility of course is that the dispersion is being caused not by distance but by some other reason, either natural or artificial, which we don't understand. But that doesn't make so much sense now because new measurements are not following that pattern, and if it were an intrinsic property you would think that they would all follow it.

I think that you need to wait a bit before concluding that it has to be aliens.

Ross 54
2017-Apr-28, 05:03 PM
I think it might be possible to explain how a number of widely separated sources of FRB radio emissions could be intentionally given the similar characteristics that have been mentioned. Before exploring that area, it would seem prudent to first clarify the basic issue.

I don't suppose that the small integer multiples of a single dispersion measurement are intrinsic to FRBs. They could just as easily be the result a modulation scheme applied to the radio energy, or some other artificial modification. Other FRBs could have other regularities imposed on them, which haven't been noted yet.
I have never claimed that FRBs have be due to extraterrestrial intelligence, only that there is a case to be made for this possibility.
Perhaps a better case than has been commonly supposed.
.

Ross 54
2017-May-02, 03:34 PM
A second group of five, within the list of known FRBs, was just found. They conform, with a high degree of accuracy, to an orderly pattern similar to that of the group of six already discussed. The members of this new group all have dispersion measurements that are small integer multiples of 158 cm to the minus three over parsec.They are as follows:


Name......... Dispersion.... Multiplier. Accuracy (%)

FRB 010125........ 790...... 5.......... 100.0

FRB 110703....... 1103.6.... 7.......... 99.7

FRB 130626....... 952.4...... 6.......... 99.5

FRB 011025....... 790........ 5........... 100.0

FRB 130628..... 469.88...... 3........... 99.1

Jens
2017-May-03, 12:41 AM
A second group of five, within the list of known FRBs, was just found.

Could you give a reference to where this was reported?

Jens
2017-May-03, 01:01 AM
A second group of five, within the list of known FRBs, was just found. They conform, with a high degree of accuracy, to an orderly pattern similar to that of the group of six already discussed. The members of this new group all have dispersion measurements that are small integer multiples of 158 cm to the minus three over parsec.

Also, I just wanted to confirm two things. First, there is no overlap between the two groups, right? I assume this because you won't get a common multiple of those two numbers very quickly. And then secondly, is the second group concentrated in a single region or are they spread out?

Ross 54
2017-May-03, 01:29 PM
That's right, there is no overlap between the two groups. Two of the five FRBs in the new group are quite near one another, FRB 010125, and FRB 011025, otherwise, these seem to be scattered about the sky. I note that the two FRBs that are near each other also have very similar dispersion measurements, 790, hence the same multiplier applies -- 5.

Jens
2017-May-03, 01:41 PM
So just as pure and utter speculation, we know that atomic states are quantized, so that they can only take on certain energies. Maybe we are seeing a similar process on galactic scales. I'm not at all arguing that this is true, but just mean to say that when we have a process that is poorly understood, we can speculate all over the board. I think we really need to wait for more data.

Ross 54
2017-May-03, 07:58 PM
We have an extraordinary and powerful phenomenon in Fast Radio Bursts. If we were to assume that a process analogous to quantized energy states exists at a galactic scale, we would be asking that a second unprecedented, extraordinary natural phenomenon be joined to the first. Requiring that two scientific marvels occur together like that, at the same times and places seems to be straining coincidence quite a bit.

01101001
2017-May-03, 08:34 PM
No it doesn't. Your sample size is still minuscule. Same as it ever was. National Geographic: Mathematical Pattern Found in Enigmatic Radio Bursts, But It’s Not E.T. (http://phenomena.nationalgeographic.com/2015/04/02/mathematical-pattern-found-in-enigmatic-radio-bursts-but-its-not-e-t/)


It’s an exciting possibility. Trouble is, the trend identified in the study isn’t likely to survive – for one simple reason: Newer observations, not included in the study or reported by New Scientist, don’t fit.
[...]
“My prediction is that this pattern will be washed out quite quickly once more fast radio bursts are found,” says West Virginia University’s Duncan Lorimer, who reported the first burst in 2007. “It’s a good example of how apparently significant results can be found in sparse data sets.”


And, as ever, units for dispersion measurement (https://en.wikipedia.org/wiki/Dispersion_%28optics%29#Dispersion_of_pulsar_emiss ions) are parsec/cm^3. Not cm^-3/parsec.

And cherry-picking (https://en.wikipedia.org/wiki/Cherry_picking) data is cherry-picking data.

Tom Mazanec
2017-Aug-27, 12:50 PM
Dr. Cramer has an Alternate View article on these critters in the new issue of Analog. It speculates that they are propelling star probes/ships in other galaxies and the beam quickly sweeps past our scopes.

Jens
2017-Aug-27, 10:38 PM
Dr. Cramer has an Alternate View article on these critters in the new issue of Analog. It speculates that they are propelling star probes/ships in other galaxies and the beam quickly sweeps past our scopes.

That's cool science fiction.