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Astronomers detect regular rhythm of radio waves, with origins unknown

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Re: Astronomers detect regular rhythm of radio waves, with origins unknown

#141

Post by antepodius »

Intermernet wrote: post #133
antepodius wrote: post #111

Earlier quoted context omitted.

Haha, nah, it was more the general idea. An amalgam of sci-fi. Greg Egan had a story where an advanced civ sends a gram-sized slug into the gas giant of a solar system, which bootstraps to machinery that 3d prints people and machinery, which is a plausible enough inspiration that I can give it here. Just remove the implausible 'nobody just decides to go bacteria-mode' aspect from Egan's far-future stories.

Do you happen to remember which story? I like Greg Egan and that one sounds interesting.

Found it eventually: https://outofthiseos.typepad.com/blog/files/GregEganGlory.pd...

All his stories are listed here, whether they be published on his website or elsewhere: https://www.gregegan.net/BIBLIOGRAPHY/Online.html

Re: Astronomers detect regular rhythm of radio waves, with origins unknown

#142

Post by brainbag »

Intermernet wrote: post #133
antepodius wrote: post #111

Earlier quoted context omitted.

Haha, nah, it was more the general idea. An amalgam of sci-fi. Greg Egan had a story where an advanced civ sends a gram-sized slug into the gas giant of a solar system, which bootstraps to machinery that 3d prints people and machinery, which is a plausible enough inspiration that I can give it here. Just remove the implausible 'nobody just decides to go bacteria-mode' aspect from Egan's far-future stories.

Do you happen to remember which story? I like Greg Egan and that one sounds interesting.

It's not the Egan book but Accelerando by Charles Stross is my favorite near-current day up to post-singularity book and it covers topics like this in a fantastic and fun way.

Re: Astronomers detect regular rhythm of radio waves, with origins unknown

#143

Post by once-in-a-while »

You probably never heard about it, but there is a religious believe that when the earth was still a Paradise (right after Creation of mankind), people could actually hear beautiful music coming from the stars!

This was made possible by the (now gone, but present before the Flood) layer of extremely cold and perfectly solid ice around our planet, which also filtered out UV light (which is well known to be one of the causes of ageing).

Re: Astronomers detect regular rhythm of radio waves, with origins unknown

#144

Post by TheOtherHobbes »

hnarn wrote: post #75
dreamcompiler wrote: post #39

Earlier quoted context omitted.

There was a time when people thought a ball of fire moving across the sky every day must be alive. The universe is full of strange phenomena perfectly explainable by physics. This is no different.

Are you saying that extraterrestrial intelligence is not “a strange phenomena perfectly explainable by physics”?

There's no evidence extraterrestrial intelligence is a phenomenon at all. [1]

We can worry about whether it's explainable by 21st century human physics when that stops being true.

[1] Although there is evidence very weird things have happened on Earth, like the recent confirmation that the US Navy UFO videos are genuine.

https://www.theguardian.com/world/2020/apr/27/pentagon-relea...

Re: Astronomers detect regular rhythm of radio waves, with origins unknown

#146

Post by namarie »

beamatronic wrote: post #12
menybuvico wrote: post #11

Earlier quoted context omitted.

As does encrypted data.

That’s why somebody needs to send out a sequence of prime numbers

It would take 500 million years to get there, if the signal was strong enough in the first place.

Re: Astronomers detect regular rhythm of radio waves, with origins unknown

#147

Post by cheerlessbog »

jrichardshaw wrote: post #104
pso wrote: post #67

Earlier quoted context omitted.

Pure speculation, isn't the most interesting time period in the signal the transition from signal to no-signal (and back again)? How high is the resolution of the sensors? Is it possible that some frequencies are blocked fractionally earlier than others? At a fine enough temporal resolution, there might be more clues regarding the source.

Good question. For many FRBs there is access to the original antenna time streams (which are essentially voltages samples at 800 MHz), so superficially that might give you 1.25ns resolution. However, the intrinsic width of the pulses seem to be more like ~1ms. That tells you something about the emission source, giving you a rough upper bound on it's size of c * 1ms ~ 300km. However, lots of interesting plasma physics…

A broader question that puzzles me, not specific to this phenomenon. Pulse length is often used to bound the size of a source in space (it cannot be smaller than light takes to traverse the object). But it’s possible that two phenomena can be correlated without being close, if there is a delayed action (akin to setting two alarm clocks and separating them in space). How can we confidently use this as evidence of size?

Re: Astronomers detect regular rhythm of radio waves, with origins unknown

#148

Post by mkl »

ganstyles wrote: post #119
vmladenov wrote: post #40

Earlier quoted context omitted.

There are a lot of cool concepts in those books, but the sophon faster-than-light communication that props up a lot of the story was a bit too much for me.

The theory of quantum entanglement is sound though, and it took a while for a single sophon to arrive before the FTL communication. Layman here, but I thought it was relatively had science/speculative fiction.

Unfortunately the sound theory of quantum entanglement disallows FTL communication: https://en.wikipedia.org/wiki/No-communication_theorem

Re: Astronomers detect regular rhythm of radio waves, with origins unknown

#149

Post by snovv_crash »

swiley wrote: post #42
EamonnMR wrote: post #30

Earlier quoted context omitted.

We should broadcast the coordinates of a distant star to see what happens.

Which space do you build the coordinates from? How will you encode them?

Give distances to pulsars with an arbitrary scale. The receiver can solve for the scale once they figure out which pulsars you are referring to. Identifying pulsars could be as easy as a pulse modulated with the frequency of the pulsar...

Re: Astronomers detect regular rhythm of radio waves, with origins unknown

#150

Post by __MatrixMan__ »

antepodius wrote: post #139
gubby wrote: post #134

Earlier quoted context omitted.

An instantiation of me from a backup, however accurate, would be no use to my sense of having survived as I would have ceased to exist and not even be aware of the copy.

That's fine! People with your philosophy of self will just cease to exist, as they presumably will refuse to optimize for likelihood of being simulated, and those with a more permissive notion of self-identity will be the ones willing to adapt to the hellish computational circumstances. (Of course, you could say that everyone's ceasing to exist, here, because your rules of what counts as a person and what's their cop…

If you haven't read Greg Egan's "Permutation City," it seems it might be right up your alley.
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