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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

#101

Post by perl4ever »

Jestar342 wrote: post #45
zoomablemind wrote: post #17

Earlier quoted context omitted.

We should beam back our commercials at them... they may just change their mind and switch to ads-free alternative.

Some of the earliest radio broadcasts are Hitler's speeches, as well as other world leaders preparing their nations for global conflict. So there's that.

There's a story in which aliens unexpectedly destroy nearly everything in the solar system and when asked why, they explain that they received transmissions of Star Trek episodes and people singing "We Are The World" and so they put together the fantasies of galactic domination with the idea that humans might be close to global unification, and decided it was time to apply a bug bomb to Earth.

In other words, the things we see as negative might not bother aliens much, if they mostly indicate we might destroy ourselves.

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

#102

Post by ellis0n »

jrichardshaw wrote: post #54

One of paper authors here. I'll try and answer some of the questions in the comments. It seems like so long ago the paper actually went public onto the arXiv, but I guess the press embargo just ended.

The more powerful technology provides the more powerful chips and telescopes and microscopes. On the basis of new data obtained with the help of new devices, new theories are created that help in creating even more microscopic components, which will help in creating even more powerful devices recursively. The singularity in the action of CHIME and AI made it possible to determine the signal; a major breakthrough is coming in all areas. Interestingly, somewhere there is a miscalculation when we can look into the space using a smartphone in real time? Any related theorems?

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

#103

Post by koheripbal »

jrichardshaw wrote: post #66
networkimprov wrote: post #60

Earlier quoted context omitted.

When are you scheduled for an appearance on the Event Horizon podcast? https://www.youtube.com/channel/UCz3qvETKooktNgCvvheuQDw

Actually looks like Shriharsh, one of the folks in the collaboration has already done it! https://www.youtube.com/watch?v=oc8FsImLUEU I guess he probably didn't talk about this because of the press embargo though.

Am I the only one that needs an RSS feed to follow a podcast channel? Maybe I'm using the wrong app?

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

#104

Post by jrichardshaw »

pso wrote: post #67
jrichardshaw wrote: post #54

One of paper authors here. I'll try and answer some of the questions in the comments. It seems like so long ago the paper actually went public onto the arXiv, but I guess the press embargo just ended.

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 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.

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

#105

Post by perl4ever »

antepodius wrote: post #76
plutonorm wrote: post #74

Earlier quoted context omitted.

That's great to hear! If some credible evidence of aliens did appear, where do you think it would come from? Tabby's Star like data? atmospheric spectra? FRB's? other? Would absolutely love to hear your thoughts :)

My guess is a nanotech slug impacting earth and turning us into grey goo/a matrioshka brain factory.

I think there was a HN thread not that long ago about speculation that (at least some) viruses come to earth from space, so perhaps it is happening all the time.

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

#106

Post by dreamcompiler »

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”?

Of course life at a deep level is just physics. But given that the information content of this signal is relatively low (regular patterns of repeats) and that the amount of energy it requires is immense, I'd bet much more heavily on a natural phenomenon than life-directed activity.

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

#107

Post by dreamcompiler »

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…

I think of multipath being about signals bouncing off other objects (reflection) and bending through media (refraction) before reaching the receiver. At the cosmic scale, I'm guessing multipath also involves gravitational lensing. Correct?

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

#108

Post by pvaldes »

perl4ever wrote: post #105
antepodius wrote: post #76

Earlier quoted context omitted.

My guess is a nanotech slug impacting earth and turning us into grey goo/a matrioshka brain factory.

I think there was a HN thread not that long ago about speculation that (at least some) viruses come to earth from space, so perhaps it is happening all the time.

Earth is perfectly capable to do it at home. Has created things more bizarre than viruses.

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

#109

Post by pvaldes »

irthomasthomas wrote: post #85
jrichardshaw wrote: post #54

One of paper authors here. I'll try and answer some of the questions in the comments. It seems like so long ago the paper actually went public onto the arXiv, but I guess the press embargo just ended.

Assuming that it is aliens, for a moment, we can not know if these aliens are friendly or hostile, right? So, given that there is a 50/50 chance of them being hostile, and given their awesome show of strength, the precautionary principal dictates that we not advertise our presence too loudly.

33 % chance of being hostile, 33% of being friendly and 33% of do not wanting anything with us in decades by cause of an humongous jet-lag

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

#110

Post by jrichardshaw »

dreamcompiler wrote: post #107
jrichardshaw wrote: post #104

Earlier quoted context omitted.

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…

I think of multipath being about signals bouncing off other objects (reflection) and bending through media (refraction) before reaching the receiver. At the cosmic scale, I'm guessing multipath also involves gravitational lensing. Correct?

There is some possibility of gravitational lensing of FRBs and people are definitely searching for it. However, in this case it is refraction caused by variation in the density of the ionised gas between us and the source (within our galaxy, the host galaxy, and at lower densities in the intervening medium).
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