Author Topic: Could Fast Radio Bursts Be Powering Alien Probes?  (Read 6394 times)

Offline Star One

  • Senior Member
  • *****
  • Posts: 8017
  • UK
  • Liked: 1281
  • Likes Given: 168
Press release from Harvard so not something to be dismissed lightly.

Quote
Cambridge, MA -
The search for extraterrestrial intelligence has looked for many different signs of alien life, from radio broadcasts to laser flashes, without success. However, newly published research suggests that mysterious phenomena called fast radio bursts could be evidence of advanced alien technology. Specifically, these bursts might be leakage from planet-sized transmitters powering interstellar probes in distant galaxies.

"Fast radio bursts are exceedingly bright given their short duration and origin at great distances, and we haven't identified a possible natural source with any confidence," said theorist Avi Loeb of the Harvard-Smithsonian Center for Astrophysics. "An artificial origin is worth contemplating and checking."

As the name implies, fast radio bursts are millisecond-long flashes of radio emission. First discovered in 2007, fewer than two dozen have been detected by gigantic radio telescopes like the Parkes Observatory in Australia or the Arecibo Observatory in Puerto Rico. They are inferred to originate from distant galaxies, billions of light-years away.

Loeb and his co-author Manasvi Lingam (Harvard University) examined the feasibility of creating a radio transmitter strong enough for it to be detectable across such immense distances. They found that, if the transmitter were solar powered, the sunlight falling on an area of a planet twice the size of the Earth would be enough to generate the needed energy. Such a vast construction project is well beyond our technology, but within the realm of possibility according to the laws of physics.

Lingam and Loeb also considered whether such a transmitter would be viable from an engineering perspective, or whether the tremendous energies involved would melt any underlying structure. Again, they found that a water-cooled device twice the size of Earth could withstand the heat.

They then asked, why build such an instrument in the first place? They argue that the most plausible use of such power is driving interstellar light sails. The amount of power involved would be sufficient to push a payload of a million tons, or about 20 times the largest cruise ships on Earth.

"That's big enough to carry living passengers across interstellar or even intergalactic distances," added Lingam.

To power a light sail, the transmitter would need to focus a beam on it continuously. Observers on Earth would see a brief flash because the sail and its host planet, star and galaxy are all moving relative to us. As a result, the beam sweeps across the sky and only points in our direction for a moment. Repeated appearances of the beam, which were observed but cannot be explained by cataclysmic astrophysical events, might provide important clues about its artificial origin.

Loeb admits that this work is speculative. When asked whether he really believes that any fast radio bursts are due to aliens, he replied, "Science isn't a matter of belief, it's a matter of evidence. Deciding what’s likely ahead of time limits the possibilities. It's worth putting ideas out there and letting the data be the judge.”

The paper reporting this work has been accepted for publication in the Astrophysical Journal Letters and is available online.

Headquartered in Cambridge, Mass., the Harvard-Smithsonian Center for Astrophysics (CfA) is a joint collaboration between the Smithsonian Astrophysical Observatory and the Harvard College Observatory. CfA scientists, organized into six research divisions, study the origin, evolution and ultimate fate of the universe.

https://www.cfa.harvard.edu/news/2017-09

Here's the pre-print paper which has been accepted for publication in Astrophysical Journal Letters.

https://arxiv.org/abs/1701.01109
« Last Edit: 03/09/2017 07:46 PM by Star One »

Offline Star One

  • Senior Member
  • *****
  • Posts: 8017
  • UK
  • Liked: 1281
  • Likes Given: 168
Re: Could Fast Radio Bursts Be Powering Alien Probes?
« Reply #1 on: 03/11/2017 08:12 AM »
I see this has now been widely reported often in a rather over excited way.

Offline gospacex

  • Senior Member
  • *****
  • Posts: 3030
  • Liked: 532
  • Likes Given: 604
Re: Could Fast Radio Bursts Be Powering Alien Probes?
« Reply #2 on: 03/13/2017 04:09 PM »
"""
NASA found that we are not alone in the Universe.
Is this a good or bad thing?
Let's ask the giant 200 km long alien cruiser currently in orbit of Saturn!
"""

Offline momerathe

  • Full Member
  • *
  • Posts: 137
  • Liked: 59
  • Likes Given: 36
Re: Could Fast Radio Bursts Be Powering Alien Probes?
« Reply #3 on: 03/15/2017 02:38 PM »
I think this is one for Betteridge's law of headlines.
thermodynamics will get you in the end

Offline Star One

  • Senior Member
  • *****
  • Posts: 8017
  • UK
  • Liked: 1281
  • Likes Given: 168
Re: Could Fast Radio Bursts Be Powering Alien Probes?
« Reply #4 on: 03/15/2017 02:59 PM »
I think this is one for Betteridge's law of headlines.

However, at least one article found that the "law" does not apply in research literature. Which this originally is.

Offline Stormbringer

  • Full Member
  • ****
  • Posts: 1285
  • Liked: 222
  • Likes Given: 80
Re: Could Fast Radio Bursts Be Powering Alien Probes?
« Reply #5 on: 03/21/2017 07:28 AM »
I hope not. I heard those alien probes hurt a lot as it is.


("Well it's what i heard!")

Provided aliens at an appropriate tech level exist (as we have speculated based on our own understanding of what is possible ) sooner or later we will detect their technological signatures.
« Last Edit: 03/21/2017 09:08 AM by Stormbringer »
When antigravity is outlawed only outlaws will have antigravity.

Offline IRobot

  • Full Member
  • ****
  • Posts: 1163
  • Portugal & Germany
  • Liked: 207
  • Likes Given: 191
Re: Could Fast Radio Bursts Be Powering Alien Probes?
« Reply #6 on: 03/21/2017 08:19 AM »
I think the most speculative side of this is to consider that beamed energy on a planetary scale is what more advanced civilizations would use.

Online KelvinZero

  • Senior Member
  • *****
  • Posts: 3476
  • Liked: 454
  • Likes Given: 115
Re: Could Fast Radio Bursts Be Powering Alien Probes?
« Reply #7 on: 03/21/2017 12:51 PM »
The huge problem with any alien hypothesis is that it has to explain why they are such underachievers.

If these radiobursts were all aliens travelling from A to B, why haven't they converted the universe yet? Any sort of exponential growth would have radically changed the universe's appearance by now.

I don't think you can even argue that every single species is obsessed with conservation, because the universe as it is, is very wasteful, with suns pouring all but a billionth of their energy into the void.
« Last Edit: 03/21/2017 12:51 PM by KelvinZero »

Offline high road

  • Full Member
  • ****
  • Posts: 680
  • Europe
  • Liked: 174
  • Likes Given: 41
Re: Could Fast Radio Bursts Be Powering Alien Probes?
« Reply #8 on: 03/21/2017 06:16 PM »
Well, if stop ignoring the tendency of civilizations to stagnate after a few centuries, and even collapse with or without outside help, and usually only recover by being replaced by another civilization, combined with the fact that going to another star gives you no new kinds of materials, no new value, little new knowledge with practical applications, etc, it's easy to see there's no drive to completely fill up solar systems enough for us to detect the IR emissions.

Civilizations don't expand mathematically. They follow the most valuable sites: the best farmlands, the richest mines, rare crops, cheap labor, etc. Take those away, and growth eventually stagnates. Not enough people would go to the nearest solar system or even the nearest planet just to have more of the same. Instead, they would continue to steadily expand the population in their own solar system/planet, with an increasing percentage of the population having less and less to do that the people that do have a job are willing to pay for. So either the population growth eventually stagnates, which I don't think is likely in the long term, or the increasing cost of sustaining an increasingly indifferent population eventually causes the civilization to collapse in on itself. And that's long before reaching a population large enough to fill Dyson spheres. Without a neighboring civilization to replace it, this cycle just keeps repeating. While the people that do settle other stars/planets, go to settle other stars long before their population reaches a density that our instruments can detect.

I know this is not a popular idea, because this is exactly the problem that Mars faces: until there is something there that people of Earth are willing to pay for, it will never attract a big enough population to act as a 'backup' of earth.

Offline Cinder

  • Full Member
  • ****
  • Posts: 562
  • Liked: 50
  • Likes Given: 183
Re: Could Fast Radio Bursts Be Powering Alien Probes?
« Reply #9 on: 03/22/2017 06:47 AM »
The huge problem with any alien hypothesis is that it has to explain why they are such underachievers.

If these radiobursts were all aliens travelling from A to B, why haven't they converted the universe yet? Any sort of exponential growth would have radically changed the universe's appearance by now.

I don't think you can even argue that every single species is obsessed with conservation, because the universe as it is, is very wasteful, with suns pouring all but a billionth of their energy into the void.
The universe doesn't get converted instantly.  There is some lapse of time where it is being converted, including a part of that lapse where the conversion is merely beginning; and then there's our local bias.  The bias of only seeing so little and extrapolating from it.  We could be seeing much less than what is out there.  The radio burst method (assuming it is artificial) may be just the tip of the iceberg, the unseen depths of the iceberg being our finite perception bias.

I would still take that same perception bias as pointing to some unknown non-living explanation.  It's just too much like the universe as we've known it to time and again dwarf our imagination (viz. flat earth and geocentrism and heaven's roof, and galaxies shining thru intergalactic voids perceived as mere stars etc), and we have such a dearth of data on these signals compared to the things in our more immediate neighbourhoods; those things that are just passing over the threshold of "certainty".
« Last Edit: 03/22/2017 06:48 AM by Cinder »
The pork must flow.

Offline ChrisWilson68

  • Senior Member
  • *****
  • Posts: 3521
  • Sunnyvale, CA
  • Liked: 2076
  • Likes Given: 2416
Re: Could Fast Radio Bursts Be Powering Alien Probes?
« Reply #10 on: 03/22/2017 07:25 AM »
Well, if stop ignoring the tendency of civilizations to stagnate after a few centuries, and even collapse with or without outside help, and usually only recover by being replaced by another civilization, combined with the fact that going to another star gives you no new kinds of materials, no new value, little new knowledge with practical applications, etc, it's easy to see there's no drive to completely fill up solar systems enough for us to detect the IR emissions.

Civilizations don't expand mathematically. They follow the most valuable sites: the best farmlands, the richest mines, rare crops, cheap labor, etc. Take those away, and growth eventually stagnates. Not enough people would go to the nearest solar system or even the nearest planet just to have more of the same. Instead, they would continue to steadily expand the population in their own solar system/planet, with an increasing percentage of the population having less and less to do that the people that do have a job are willing to pay for. So either the population growth eventually stagnates, which I don't think is likely in the long term, or the increasing cost of sustaining an increasingly indifferent population eventually causes the civilization to collapse in on itself. And that's long before reaching a population large enough to fill Dyson spheres. Without a neighboring civilization to replace it, this cycle just keeps repeating. While the people that do settle other stars/planets, go to settle other stars long before their population reaches a density that our instruments can detect.

I know this is not a popular idea, because this is exactly the problem that Mars faces: until there is something there that people of Earth are willing to pay for, it will never attract a big enough population to act as a 'backup' of earth.

You're taking the wrong lessons from history.  Human societies always expand to the limits of the carrying capacity of whatever places they inhabit, and they always expand into all available habitats.

Sure, there are "collapses" in the sense of breakup of larger political entities into smaller ones and replacement of some political entities with others.  That sometimes leads to a reduction in population and/or a reduction in the carrying capacity of an area.  But the population never stays much below the carrying capacity for long.

Any collection of beings would inevitably have to follow the same pattern unless somehow constrained by a single central entity.  That's just because whichever individuals reproduce more will become more prevalent.  A civilization can't help but grow until it reaches the carrying capacity of whatever environment it can expand into, unless a single central entity enforces some sort of rule to keep it from doing so.

We tend to forget that because it's been obscured by dramatic short-term changes in Western society in recent centuries, but that doesn't make it untrue.

Offline notsorandom

  • Full Member
  • ****
  • Posts: 1679
  • Ohio
  • Liked: 373
  • Likes Given: 87
Re: Could Fast Radio Bursts Be Powering Alien Probes?
« Reply #11 on: 03/22/2017 01:08 PM »
The lack of any relatively local aliens scooting around in their light sail starships isn't fatal to the hypothesis. The FRBs have been only observed in galaxies billions of light years away. The method of travel isn't faster than light. So the aliens would show up some time after their beams could be detected equivalent to how much slower their ships are. Likewise if we assume an alien civilization spreading out in all directions then they would do so only as fast as their ships could take them and their efforts to do so would be detectable long before their ships spread out. That also assume that they don't spend any time stopping to colonize or get some fresh air which would add even more time between the first detections and their arrival.

Assuming they could get up to 50% of c and they were 1 billion light years from Earth their first ships wouldn't start showing up any sooner than a billion years after they were first detected. If we are waiting for some company to drop by it gets even worse if we use some more conservative figures. FRB 121102 is thought to have happened 3 billion LY away and if their travel speed is only 20% (Breakthrough Starshot's speed) of c then it would take 15 billion years for them to get here and they would have been detectable for 12 billion years.
« Last Edit: 03/22/2017 02:04 PM by notsorandom »

Offline high road

  • Full Member
  • ****
  • Posts: 680
  • Europe
  • Liked: 174
  • Likes Given: 41
Re: Could Fast Radio Bursts Be Powering Alien Probes?
« Reply #12 on: 03/22/2017 07:20 PM »
Well, if stop ignoring the tendency of civilizations to stagnate after a few centuries, and even collapse with or without outside help, and usually only recover by being replaced by another civilization, combined with the fact that going to another star gives you no new kinds of materials, no new value, little new knowledge with practical applications, etc, it's easy to see there's no drive to completely fill up solar systems enough for us to detect the IR emissions.

Civilizations don't expand mathematically. They follow the most valuable sites: the best farmlands, the richest mines, rare crops, cheap labor, etc. Take those away, and growth eventually stagnates. Not enough people would go to the nearest solar system or even the nearest planet just to have more of the same. Instead, they would continue to steadily expand the population in their own solar system/planet, with an increasing percentage of the population having less and less to do that the people that do have a job are willing to pay for. So either the population growth eventually stagnates, which I don't think is likely in the long term, or the increasing cost of sustaining an increasingly indifferent population eventually causes the civilization to collapse in on itself. And that's long before reaching a population large enough to fill Dyson spheres. Without a neighboring civilization to replace it, this cycle just keeps repeating. While the people that do settle other stars/planets, go to settle other stars long before their population reaches a density that our instruments can detect.

I know this is not a popular idea, because this is exactly the problem that Mars faces: until there is something there that people of Earth are willing to pay for, it will never attract a big enough population to act as a 'backup' of earth.

You're taking the wrong lessons from history.  Human societies always expand to the limits of the carrying capacity of whatever places they inhabit, and they always expand into all available habitats.

Sure, there are "collapses" in the sense of breakup of larger political entities into smaller ones and replacement of some political entities with others.  That sometimes leads to a reduction in population and/or a reduction in the carrying capacity of an area.  But the population never stays much below the carrying capacity for long.

Any collection of beings would inevitably have to follow the same pattern unless somehow constrained by a single central entity.  That's just because whichever individuals reproduce more will become more prevalent.  A civilization can't help but grow until it reaches the carrying capacity of whatever environment it can expand into, unless a single central entity enforces some sort of rule to keep it from doing so.

We tend to forget that because it's been obscured by dramatic short-term changes in Western society in recent centuries, but that doesn't make it untrue.

So there are no ghost towns in the US? No deserted gold rush villages? No villages around route 66 that now have a fraction of their previous population because of highways? As far as I know, changes in the local carrying capacity is not why these towns failed.

People have been concentrating in cities for (tens of?) thousands of years, in far greater numbers than the carrying capacity of the local area, importing food from other regions, sometimes even separated by a sea. The size of the city only limited by the value it could create, to import whatever the inhabitants wanted to pay for. And eventually declining as whatever valuable goods or services the city produces, is exhausted or no longer unique or valuable. Food production is for farming villages. And the population of those farming villages has been impacted more by how much food can be produced per hour of labor (more food per man-hour meaning less people per km²), rather than how many people can be fed with the local produce.

Employment problems like the rust belt and coal country have been encountered through all ages. That is what ultimately drives population sizes. Not food, unless finding food is a full time job for most of the population.
« Last Edit: 03/22/2017 07:35 PM by high road »

Online KelvinZero

  • Senior Member
  • *****
  • Posts: 3476
  • Liked: 454
  • Likes Given: 115
Re: Could Fast Radio Bursts Be Powering Alien Probes?
« Reply #13 on: 03/24/2017 06:24 AM »
The universe doesn't get converted instantly.  There is some lapse of time where it is being converted,
I won't continue this here because I would be pulling the thread too far off topic.

This is a more general problem that has been explored in detail. Lots of people have done the math and come to the same conclusion. It is pretty much the Fermi paradox which to me is an argument that interstellar civilisations must be exceedingly rare, very possibly none at all within the observable universe. If they exist they are strangely underachieving and it speaks very poorly for the odds of us ever amounting to anything, so personally I optimistically hope to never see signs of them. We will have to go out there and make our own aliens.

Online spacenut

  • Senior Member
  • *****
  • Posts: 2122
  • East Alabama
  • Liked: 298
  • Likes Given: 191
Re: Could Fast Radio Bursts Be Powering Alien Probes?
« Reply #14 on: 03/24/2017 12:58 PM »
Look at Japan.  They import 50% of their food, import iron ore, coal, and limestone to make steel.  Basically they import almost all their raw materials and are heavy into manufacturing.  They once tried to take the raw materials by military expansion leading to WWII.  Now they trade for their raw materials and have become richer than they were before WWII. 

I have a book around here somewhere that says with nuclear power, the United States could sustain a population the size of China with our current standard of living.  Lots of big cities, unlimited power, vegetables grown in greenhouses instead of farmland.  Farmlands used for grain and cattle ranching.  Much like some of the Martian agriculture envisioning.

Anyway, this is off topic of alien probes.  If there are aliens, they may be expanding outside their solar system.  We are only just beginning.  What we learn from Martian agriculture, can be applied to earth to increase production. 

Offline Oli

  • Senior Member
  • *****
  • Posts: 2103
  • Liked: 374
  • Likes Given: 55
Re: Could Fast Radio Bursts Be Powering Alien Probes?
« Reply #15 on: 03/25/2017 01:21 AM »
Why would Aliens use radio waves though? I thought light sail concepts use lasers...

Edit: They mention potential reasons in the footnote on page 2 of the paper.
« Last Edit: 03/25/2017 01:44 AM by Oli »

Offline Orbiter

  • Senior Member
  • *****
  • Posts: 2182
  • Florida
  • Liked: 385
  • Likes Given: 908
Re: Could Fast Radio Bursts Be Powering Alien Probes?
« Reply #16 on: 03/25/2017 01:39 AM »
Why would alien civilizations in different galaxies use the exact same technique for interstellar travel is my question.
Attended space missions: STS-114, STS-124, STS-128, STS-135, Atlas V "Curiosity", Delta IV Heavy NROL-15, Atlas V MUOS-2, Delta IV Heavy NROL-37, SpaceX CRS-9, SpaceX JCSAT-16, Atlas V GOES-R, SpaceX SES-11.

Offline Phil Stooke

  • Full Member
  • ***
  • Posts: 342
  • Canada
  • Liked: 191
  • Likes Given: 0
Re: Could Fast Radio Bursts Be Powering Alien Probes?
« Reply #17 on: 03/25/2017 01:50 AM »
"I have a book around here somewhere that says with nuclear power, the United States could sustain a population the size of China with our current standard of living. "

That's what these poor aliens are trying to escape.

Offline Bob Shaw

  • Full Member
  • ****
  • Posts: 959
  • Liked: 356
  • Likes Given: 334
Re: Could Fast Radio Bursts Be Powering Alien Probes?
« Reply #18 on: 03/25/2017 02:58 AM »
FRBs are perhaps simply the anomalies du'jour, oddities seeking a semi-feasible explanation as regards ETI. Somehow, I doubt that we're seeing anything other than a natural event here.

There are, however, things which *might* be out there which *would* be rather more persuasive. These range from pan-galactic megastructures through to inappropriate IR individual signatures across otherwise normal galaxies and unusal metalicities/rotation/elements in otherwise standard stars. Sadly, there's no evidence of anything across the depths of time and space. We can calculate the rate at which self-replicating machine cultures might spread across individual galaxies at sub-light speeds (never mind more fragile organic cultures) and even locally we see no evidence of stellar industry.

There appear to be many opportunities for life to exist even in our own Solar System, but such life is likely to be highly adapted slime in most cases, and I fear that our own species may well be just about all there is in terms of intelligent life within the readily observable part of the universe. This is sad, but demonstrates that we need to nurture our own species and our planet - there are no lifeboats, nor is there anyone out there to save us from our mistakes. We have to grow up as a species!
« Last Edit: 03/25/2017 02:59 AM by Bob Shaw »

Offline Mark K

  • Member
  • Posts: 50
  • Wisconsin
  • Liked: 20
  • Likes Given: 5
Re: Could Fast Radio Bursts Be Powering Alien Probes?
« Reply #19 on: 03/25/2017 03:22 AM »
The universe doesn't get converted instantly.  There is some lapse of time where it is being converted,
I won't continue this here because I would be pulling the thread too far off topic.

This is a more general problem that has been explored in detail. Lots of people have done the math and come to the same conclusion.

Yeah ... oh wait the studies I have seen all project no visible civilizations at very reasonable probabilities. It is a universe where life would not be real detectable. Look at old  BIS journals from decades ago. Plus some G. Landis papers - with very reasonable assumptions, The models predict nobody over running anything. Space is big and time is long and travel energy costs are high. I haven't  actually seen an in depth study that came to another conclusion. Just some simple projections like Fermi's and a few others the other way.
 

Tags: