
With a Second Repeating Radio Burst, Astronomers Close in on an Explanation - spzx
https://www.quantamagazine.org/astronomers-now-think-they-can-explain-fast-radio-bursts-20190228/
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HocusLocus
The closer we are to discovering what causes radio bursts, the closer we come
to doom.

"We've figured out what causes them!" he spoke to the bored conference
audience. They sat up quickly. He continued, "It happens whenever any advanced
civilization builds one of these." He takes a strangely shaped device from his
pocket. There is a murmur from the crowd. "During the building of this
prototype, we have--" and his tentacle fumbled for a moment, and it dropped
onto the floor.

4 MILLION YEARS LATER

Astronomers have detected their third fast radio burst, and have almost
gathered enough data to discover what causes them.

~~~
SiempreViernes
Uh, actually it is _repeating_ radio bursts that are very rare. We’ve seen
quite a few of the one-shot ones.

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superkuh
There's no one explanation for fast radio bursts. They are a class of things
defined by their transient nature but from one to another their spectral
appearance can be drastically different. Even from the ones discovered so far
it's obvious they're not all one thing.

What remains the same is that they're from really far away and they're short.
They can tell they're from far away because the broadband pulse has dispersed
relative to frequency and the charges along the line of sight from us to it
retard the progress of the longer wavelengths more. So it comes in like a
'swoop' of decreasing frequency on on the spectrum vs. time when reality it
was more like a broad pulse.

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lifeisstillgood
I have to say it, but I am quite disappointed it's not intergalactic weapons
fire.

Or rather, I am quite disappointed that _if_ there is anyone out there, they
are not leaving big enough forensics.

(but well done to Occam's razor and the hard working scientists who support
it)

~~~
praptak
We sort of assume without proof that every civilization optimizes for
continuation of its own existence. What if it's false and civilizations just
detach from the utility function of evolution and choose not to exist anymore?

~~~
krapp
What we seem to assume is that every civilization optimizes for technological
progress and territorial expansion.

That a species would be capable of interstellar travel and not spend millions
of years aggressively exploring and colonizing the galaxy as a first priority
just seems _too_ alien.

~~~
freedomben
Based on the excellent documentary series "Star Trek" I think it's safe to
assume there are species that would colonize the galaxy.

But on a more serious note. You make an interesting point. Our entire history
has been a fight for survival against a merciless environment (and other
species). It's a core part of our DNA to colonize, grow, and thrive.

But assuming that is representative of what all life would go through may not
be safe. It's hard for me to imagine how evolution would create life without
the threat of killing off bad mutations, but that doesn't make it impossible.
Definitely good to keep an open mind.

~~~
krapp
Our history has been a fight to survive and thrive where it's been possible to
survive and thrive within the environment of our own ecosystem. Despite some
exploration, we haven't exactly built cities in Antarctica or the ocean floor,
because we can't thrive there. Whatever drive to colonize and grow that might
exist in our DNA doesn't extend into space. There's no natural evolutionary
path into space - it's unimaginably vast, it costs a ludicrous amount of
effort and energy expenditure just to reach orbit, and once you're there
literally every aspect of it is hostile to life, and every step is
exponentially more expensive and deadly.

I can imagine a species with the same drives as ours, but which doesn't
advance beyond colonizing its own solar system, or sending probes to nearby
stars, because I can imagine that happening with _us._ I suspect that, as far
as space exploration (much less long term colonization) goes, politics,
economics and culture matter far more than our innate drive to find whatever's
over the next mountain. We had the capability for manned lunar landings, but
didn't follow up with moon-bases or a colony on Mars because that initial
drive was fueled by competition and fear between superpowers. We gave up that
capability because there was nothing interesting on the moon, and the public
stopped caring, and anything but probes started to seem like a boondoggle.

And we're lucky enough to have a moon and a couple of nearby planets to keep
us curious. How many technologically advanced but "landlocked" civilizations
might there be, who don't venture into space because there's nothing to even
theoretically colonize for hundreds, if not thousands, of light years?

Of course, if we had warp drives, things would be different. But the Fermi
Paradox suggests that such things are either not possible, or somehow not
reliable over the long term, possibly due to energy requirements or something.

~~~
freedomben
Very interesting indeed, and that makes a lot of sense. I wonder if the Elon
Musk style reasons would kick in (such as Earth is no longer hospitable to us
because AI has completely taken over), which would definitely change the fact
that Earth is a thriving environment for us. But short of that, I could
definitely see you being right.

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pmoriarty
I wonder what these would sound like if they were slowed down to be audible to
human hearing.

~~~
krapp
"Thunder" by Imagine Dragons.

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iFred
I had been hoping to some degree that this and Oumuamua were stronger pieces
of hard to answer bits that said maybe, just maybe, these could not be easily
explained away as "not from other intelligence". I guess I am just left with
long, weirdly spinning, rock thing.

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droptablemain
Spoiler alert: Not aliens

~~~
bradd
darn

