It seems like so long ago the paper actually went public onto the arXiv, but I guess the press embargo just ended.
However, lots of interesting plasma physics effect occur between us and the FRB. The dominant thing that happens is that low frequencies arrive later than high frequencies (as they travel slow in a plasma). This causes the FRB to be smeared over many seconds rather than a millisecond. There's also multi path interference effects and an whole bunch of other stuff that happens. So actual the temporal structure of the burst tells you much more about the intervening medium than it does about the source.
The most useful follow up has been for repeating FRBs. What happens there is that the discovery telescope tells you were it is roughly, and you know it repeats, so you can point a high resolution radio telescope (something like https://www.evlbi.org) to get a more precise location and then you can follow up with other telescopes.
One thing telescopes like CHIME are trying to do in the near future is to build their own long baseline station to give much higher resolution, such that they can get localisation on bursts which don't repeat, and do better follow up.
I think astronomers often make it worse. I mean, we like thinking about why things are actually aliens as much as anyone else (LGM1 was already mentioned), and while we mostly try to restrain ourselves, every now and again a famous astronomer breaks and lets out a paper about it.
It's kind of hypocritical to use nod-wink-aliens-clickbait to drum up media attention, then ridicule the first rube who asks if aliens could possibly be involved.
I guess he probably didn't talk about this because of the press embargo though.
I'm not super involved on the FRB side of CHIME, so I'm not 100% clear what is public and what isn't. But you can an idea from public info around the internet. I think the last total number made public was over 700 in March this year, and the previous one 30 in October 2018 (https://aasnova.org/2020/03/13/chime-detects-even-more-repea...).
In fact, when the first pulsar was discovered, it was (somewhat jokingly) called LGM-1 for "little green men".
I'm sure the news hype cycle will come up with similar ideas this time, and I'm just as sure that we'll find a perfectly reasonable explanation not involving intelligent, extraterrestrial life forms.
"Greetings from ___." "Oh, hello... uhh, so those signals were your house and not a trefoil of two black holes and a quasar?
Also, if an alien happens to be shining a beam at us rhythmically, that's also "explained" by physics but we won't actually know if the source is a natural phenomena or an alien shining his super flashlight at us.
Same thing with UFOs, despite the fact that there's been decades of R&D into weaponizing and developing novel UAVs.
If it's powerful enough to be seen 500 million ly away, one of the two orbiting objects is going to be a black hole.
I don't think either needs to be a black hole though. What I consider the most plausible candidate for emission is probably magnetars (i.e. neutron stars with extremely strong magnetic fields), and there's no reason the companion would need to be a black hole either, you just need a companion that gives a 16 day orbit and that's very easy to do with another star or neutron star.
This galactic magnetar (https://en.wikipedia.org/wiki/SGR_1806%E2%88%9220) affected the Earth's atmosphere.
Just how luminous can an extra-galactic one be? Is the FRB an axial emission?
You can imagine other cyclical processes, but I don't know any are realistic.
[1] https://arxiv.org/abs/2001.10275
[2] https://www.vice.com/en_us/article/wxexwz/something-in-deep-...
[3] https://en.wikipedia.org/wiki/Canadian_Hydrogen_Intensity_Ma...
I realize there is most likely an explanation that doesn’t require intelligent alien life, but that screams Dark Forest Theory.
This article describes a source that seems to start and stop at regular intervals of several days (much longer than any known pulsar's rotational period) but within the active intervals, the bursts appear to be random. That suggests a more complex mechanism is at work.
The only exception to this is the Crab pulsar, which is observed to occasionally have "giant pulses" which are 1000s of times brighter than a typical pulse. If you put the a somewhat brighter version of the Crab pulsar in an FRB host galaxy at the low end of the known distances, you might just about be able to see it.
I know the odds of this being life are (literally) astronomically low, but every time I hear news like this, I can't help hoping there's another species out there that found the will & the way to reach out.
Don't known much about astronomy, but day as a unit of time is just a constant specific to our particular solar system. I guess a function of the sizes of the sun and the planets here. There should be nothing special about it. To think that 500M light years away there is something that has similar time proportions to be observed here as periodic is amazing by itself.
So the period is neither an integer multiple of days, nor exactly the same each time. There's some small variance involved - about 1%.
It is a high-risk low-reward strategy.
in the data stream, sure, but the underlying data framing would probably still have very strong patterns as compared to true noise
My pet theory for a while has been that they use point-to-point communications (lasers), rather than wasteful omnidirectional radio waves, so that you have to get very lucky in order to eavesdrop on them.
I wonder how these aliens manage to work only for 4 days and then rest for almost 2 whole weeks. They must be quite advanced.
Or some kind of giant vessel arriving to a close star.
Could be no luck at all too.
How are they able to know how far it's coming from?
And even if there was, we don't understand the mechanism behind FRBs, so we wouldn't necessarily be able to distinguish a Doppler shift from some other effect that caused the frequency to change.
Yes, you know what it is. :D
So, it's aliens. what would they possible be communicating?
What kind of information would actually matter to communicate over 500 million light years?
I bet it would be: a way to reply
I wouldn't bother to try to send intructions for them - us - to build another 500 million light-year capable transmitter,
But maybe, just maybe, they could be sending information for making us able to build a wormhole.
A we'd know where the other extreme would be located, so we "just" need to build one and point it to them.
