Transmit data into a black hole?

[jonnyL]

I've been told it's impossible to transmit data into the nearest blackhole, at some 3000 light years distance.

Laser diffraction, and sheer distance;  - I've been told - make this impossible.

Would anyone care to theorise how it could be done, using existing technology- satellite, radio telescopes, or ideally via light?

This is a live project

Thanks in advance

Jon

 

 

[Green Baron]

I would like to if i understood the question.

Sure could one transmit something in that direction. It'll arrive very much diluted due to the distance but it'll arrive. In 3kyr. Data that goes in a black hole is gone, there is no more to say.

Live project ?

 

[Snark]

Hello, and welcome to the forums!

58 minutes ago, jonnyL said:

I've been told it's impossible to transmit data into the nearest blackhole, at some 3000 light years distance.

Laser diffraction, and sheer distance;  - I've been told - make this impossible.

...I'm a bit confused by the question.  It's not impossible to transmit information that far, merely very difficult-- it's an engineering problem, not some fundamental limitation of the laws of physics.  There's also the question of what exactly do you mean by "data".

But what really confuses me is the context.  What do you mean by transmitting "into a black hole"?  Once it goes in, it's not "data" anymore, it's just "energy."  There's no "data" in a black hole; you're literally transmitting it into the one place in the universe where there is zero informational content.  A black hole has a mass, an angular momentum, and an electric charge; that's basically it.  Specify those three numbers and you've fully specified the hole, physically.  There's no "data".  So it's hard to see the point of such an operation, never mind the engineering difficulties.

So... what's the idea behind the thought experiment, here?

[Green Baron]

Maybe, what you're looking for is the "information paradox" of a black hole. Quite a few sites on the internet explain it.

tl;dr: yeah, having enough power to transmit a signal over 3kly, you can send something in, but you'll never get it back. "Never" means in the time of the universe because it has left spacetime.

 

[jonnyL]

Thankyou both for your quick response. As you may tell this certainly isn't my area of expertise, but I am looking for a solution whereby I could 'transmit' a data signal containing video (so several gb) 'into' a black hole- that is, directly 'at it'.

The premise of the idea is two fold. If i know from where it was sent, at what time and at where it was going;  I create in theory a digital timecapsule that can be 'unlocked' using any mobile device in the future.

The idea of this data travelling towards a black hole then also has the potential to be 'received' and intercepted by another form of intelligence.

To be clear and to summarise, this would be for a brand activation event. For this brand, I'd like to explore the reality of transmitting a data (video) package towards a black hole, and have a degree of certainty that some of this data would reach its destination, 3000 light years away. I'm looking for a solution to this problem, if you or anyone could help me. I'd need to know how to physically do this. 

Anyone interested?

[jonnyL]

1 minute ago, Green Baron said:

Maybe, what you're looking for is the "information paradox" of a black hole. Quite a few sites on the internet explain it.

tl;dr: yeah, having enough power to transmit a signal over 3kly, you can send something in, but you'll never get it back. "Never" means in the time of the universe because it has left spacetime.

 

Yes- I'm not expecting to get anything back, more the concept of being able to ensure I can get data TO IT

[YNM]

1 hour ago, jonnyL said:

... it's impossible to transmit data into the nearest blackhole, at some 3000 light years distance.

...

I'll just try to see the phrases.

"Transmit" : send / give / move / feed

"Data" : If we assume data is information, and information is entropy (bad ref), then it's energy / entropy. But there's one caveat : blackholes might be the most entropy-full thing ever ? I don't know.

So, could you ? Well, seeing the phrases, blackholes do devour entropy, devour data, devour mass and energy; so you don't need to send one - it's already doing it. Everything that ever enters a blackhole is gone for good. That includes however small amount of data you're trying to send it and actually interact enough to be "inside" it.

But, some bright spark realize that holding entropy like that isn't good, and this is what they (presumably) give back.

Anyway, before going further :

And fresh from the oven (at time of post) :

[Snark]

1 hour ago, jonnyL said:

If i know from where it was sent, at what time and at where it was going;  I create in theory a digital timecapsule that can be 'unlocked' using any mobile device in the future.

Well, not really.  It can only be received by a mobile device that's already in front of the signal, which of course excludes you or any other person who was around at the time & place of transmission, because the signal is fleeing from all of us at the speed of light and therefore none of us can never catch up to it.

So you'd basically be limited to some hypothetical alien being that, 1. is in the right direction to receive the signal, 2. is far enough away that it's already in front of the signal when the signal arrives, 3. happens to be listening, and 4. can figure out how to decode the signal.

But within those limitations, sure. 

1 hour ago, jonnyL said:

The idea of this data travelling towards a black hole then also has the potential to be 'received' and intercepted by another form of intelligence.

...yes... but thus the question, why a black hole.  As opposed to just beaming it towards some random point in the sky, or towards a star cluster, or something.

Sending data into a black hole is sending it to literally the worst possible place in the universe if you want it to be received by anything.

It's basically the equivalent of being on a desert island and wanting to send a "message in a bottle", so I write the message down, then burn the paper and grind the ashes into powder and then put the powder into a blast furnace to decompose it to its individual molecules.  Very dramatic, sure, but not super effective as a way of getting the message to anyone. 

[Steel]

1 hour ago, jonnyL said:

Thankyou both for your quick response. As you may tell this certainly isn't my area of expertise, but I am looking for a solution whereby I could 'transmit' a data signal containing video (so several gb) 'into' a black hole- that is, directly 'at it'.

The premise of the idea is two fold. If i know from where it was sent, at what time and at where it was going;  I create in theory a digital timecapsule that can be 'unlocked' using any mobile device in the future.

The idea of this data travelling towards a black hole then also has the potential to be 'received' and intercepted by another form of intelligence.

To be clear and to summarise, this would be for a brand activation event. For this brand, I'd like to explore the reality of transmitting a data (video) package towards a black hole, and have a degree of certainty that some of this data would reach its destination, 3000 light years away. I'm looking for a solution to this problem, if you or anyone could help me. I'd need to know how to physically do this. 

Anyone interested?

Ok, if it's just you or a small company behind this then it is quite difficult, the power required to ensure that any measurable trace of the signal (a video signal is very complex) would exist 3000 ly away could power a city (if not a small country)

The Aricebo Message [1] is the closest thing humanity has done to this before AFAIK, and that took 1 MW of power just to send a simple binary message encoded onto a radio wave to a star to a galaxy 25,000 ly away, and it still only transmitted at 10 bits per second. So either you transmit like this and it would take several years to transmit a video (and thus several years to receive it), or transmit at a higher speed, but likely use far more power in the process.

[1] https://en.wikipedia.org/wiki/Arecibo_message

Edited July 24, 2017 by Steel

[sevenperforce]

In theory you can use a handheld pulsed laser to deliver the binary code of whatever message you want to deliver, and in theory it could be possible to pick it up from anywhere in the direction of the beam...but realistically the hypothetical alien radio receiver dish would need to be about ten times the size of the solar system to actually pick it up at just a few dozen lightyears.

On the other hand, sending a signal toward a black hole is actually NOT a bad idea, because although nothing which actually reaches the black hole will ever be recovered, the black hole can effectively "slingshot" your signal in all directions at once, both amplifying and scattering it so that a wider range of observers would be (theoretically) able to receive it.

[Green Baron]

All of the above: plus humans radiate all over the magnetic spectrum into the universe, mostly banal nonsense. Your message would be like the sound of an ant under a Saturn V at ignition. Also it takes 3.000 years to your designated target, which is unable to respond. If you're interested in an answer you must have patience.

All this "sending a message to the stars and hoping for an answer" is a refreshingly human attitude ignoring time and distance and capabilities of sender and receiver establishing a meaningful contact.

Over and out :-)

[Snark]

13 minutes ago, sevenperforce said:

On the other hand, sending a signal toward a black hole is actually NOT a bad idea, because although nothing which actually reaches the black hole will ever be recovered, the black hole can effectively "slingshot" your signal in all directions at once, both amplifying and scattering it so that a wider range of observers would be (theoretically) able to receive it.

Nope.  Scatter, yes.  Amplify, absolutely not.  That portion of the transmission that doesn't actually intersect the Schwartzchild radius can get bent every which way, but it's not really any different than if it hit a curved mirror.  And if you wanted an omnidirectional broadcast, why bother focusing your initial transmission in the first place?

Certainly the black hole wouldn't add any energy to the signal simply by virtue of passing by it.  The light would gain energy falling towards it, then lose that energy as it recedes again.  It's not as if the light beam is performing an Oberth maneuver, or something.  At most you might get some dopplering up (or down) if the black hole's motion relative to you has a significant radial component, but again, that's not any different than if it were a mirror moving towards or away from you.

Scattering = not concentrated = lower signal strength = harder to receive.  So it would do the exact opposite of "amplifying".

[HebaruSan]

Send a sub light speed probe towards Tabby's Star. 1280 light years instead of 3000, there are already speculations about that system being inhabited (= hype for your press release), and a slower craft won't suffer from beam divergence and could be detected, captured, and analyzed in depth even if you weren't expecting it (with electromagnetic transmissions, either your receiver is already pointed in the right direction when it arrives or you're out of luck).

[sevenperforce]

6 minutes ago, Green Baron said:

All of the above: plus humans radiate all over the magnetic spectrum into the universe, mostly banal nonsense. Your message would be like the sound of an ant under a Saturn V at ignition. Also it takes 3.000 years to your designated target, which is unable to respond. If you're interested in an answer you must have patience.

All this "sending a message to the stars and hoping for an answer" is a refreshingly human attitude ignoring time and distance and capabilities of sender and receiver establishing a meaningful contact.

Over and out :-)

It sounds like he's doing some kind of marketing stunt...in which case sending something toward a "black hole lens" such that it will be sent out into the rest of the galaxy is kinda cool, even though obviously it's not truly able to be received in any meaningful way.

3 minutes ago, Snark said:

Nope.  Scatter, yes.  Amplify, absolutely not.  That portion of the transmission that doesn't actually intersect the Schwartzchild radius can get bent every which way, but it's not really any different than if it hit a curved mirror.  And if you wanted an omnidirectional broadcast, why bother focusing your initial transmission in the first place?

Certainly the black hole wouldn't add any energy to the signal simply by virtue of passing by it.  The light would gain energy falling towards it, then lose that energy as it recedes again.  It's not as if the light beam is performing an Oberth maneuver, or something.  At most you might get some dopplering up (or down) if the black hole's motion relative to you has a significant radial component, but again, that's not any different than if it were a mirror moving towards or away from you.

Scattering = not concentrated = lower signal strength = harder to receive.  So it would do the exact opposite of "amplifying".

It will be "amplified" in a very loose sense for an observer directly on the other side of the black hole via gravitational lensing.

1 minute ago, HebaruSan said:

Send a sub light speed probe towards Tabby's Star. 1280 light years instead of 3000, there are already speculations about that system being inhabited (= hype for your press release), and a slower craft won't suffer from beam divergence and could be detected, captured, and analyzed in depth even if you weren't expecting it (with electromagnetic transmissions, either your receiver is already pointed in the right direction when it arrives or you're out of luck).

I doubt our intrepid OP has the funds for an interstellar probe.

[Snark]

9 minutes ago, sevenperforce said:

It sounds like he's doing some kind of marketing stunt...in which case sending something toward a "black hole lens" such that it will be sent out into the rest of the galaxy is kinda cool

And also pointless, from a scientific point of view, since if he wanted an omnidirectional broadcast across the galaxy, he might as well just broadcast omnidirectionally.  Sure, if it's a marketing stunt, "mumble mumble black hole mumble mumble" sounds pretty cool, and there's nothing wrong with that.    But if all one is interested in is sounding cool without any scientific justification, why bother asking here in the first place?

9 minutes ago, sevenperforce said:

It will be "amplified" in a very loose sense for an observer directly on the other side of the black hole via gravitational lensing.

Sure, for an observer who happens to be sitting in exactly the right spot.  And, by extension, observers outside of that spot would get less of a signal.  Since the volume of space where the signal intensity would go down is vastly, hugely, literally astronomically bigger than the volume of space where it would go up, then on the whole, beaming towards a black hole would be a net negative if your objective is to get somebody to receive the signal.

The original post I was responding to, though, didn't say "focus"-- it said "amplify", and also used the term "slingshot", which seemed to be implying that the black hole would actually be adding energy to the signal, which is not the case.  It also was saying that it would scatter the signal (which it would), which is the exact opposite of focusing, and would make the signal harder to receive.  And the post was saying that a black hole would be a good target, whereas it would actually be a direction best avoided.

[HebaruSan]

6 minutes ago, sevenperforce said:

I doubt our intrepid OP has the funds for an interstellar probe.

So far, no part of this project seems feasible. I simply chose to ignore a different impossible thing. 

[Snark]

1 minute ago, HebaruSan said:

I simply chose to ignore a different impossible thing. 

Not impossible.  Just very, very improbable. 

[sevenperforce]

15 minutes ago, Snark said:

The original post I was responding to, though, didn't say "focus"-- it said "amplify", and also used the term "slingshot", which seemed to be implying that the black hole would actually be adding energy to the signal, which is not the case.  It also was saying that it would scatter the signal (which it would), which is the exact opposite of focusing, and would make the signal harder to receive.  And the post was saying that a black hole would be a good target, whereas it would actually be a direction best avoided.

The black hole would be a good target from a marketing sense: having a specific target with some meaningful destination. Obviously the signal is never going to be received.

I did not mean slingshot in the Oberth sense; rather, I meant that photons tangent to the photon sphere will be flung out in an infinite number of directions. 

[wumpus]

5 hours ago, Snark said:

Hello, and welcome to the forums!

...I'm a bit confused by the question.  It's not impossible to transmit information that far, merely very difficult-- it's an engineering problem, not some fundamental limitation of the laws of physics.  There's also the question of what exactly do you mean by "data".

Note: I've been lead to believe that there are limits to just how much power you can focus to such an extreme degree (I've never seen such claims derived from equations I'm familiar with, but I've never been familiar with much past Maxwell's equations).  I *know* there are mathematical limitations on how much bandwidth you can transmit depending on how much power you can deliver (if only to overcome cosmic background noise).  Assuming the black hole was sufficiently noisy across the entire spectrum (or sufficiently far away), and the goal was to send the information across the Schwarzschild radius it might take a lot longer than you would expect to transmit each bit.

Doing this across the universe is of course even worse.  We've seen *a star* at something like 13 light years.  Now imagine how much energy a bright star has, and that gives you just one bit.  Obviously we aren't sending messages to 10 digit light years, regardless of whether they are being bombarded with noise or not.

- see Shannon's laws of channel capacity for the mathematical limits on sending data
- can't comment on the physics side
- you might manage to block out the noise from other directions (although of course all bets are off inside a black hole), but there will still be all the background radiation in the direction between transmitter and receiver.  That is absolute.  Expect some really weird issues from "lock on" issues and being able to focus both spatially and temporally.  A lot of signal analysis hits almost the same issues of Heisenberg's uncertainty principle.

The whole point of this is that "merely very difficult" might require physical and mathematical limits to require some vast amount of energy and power (you don't necessarily need the power, just expect to need more energy over time than if you used a lot of power) to simply send one bit.  Hitting the limits of anything gets complicated, and sending messages to black holes sounds like it could easily hit some limits.

[Snark]

40 minutes ago, wumpus said:

Note: I've been lead to believe that there are limits to just how much power you can focus to such an extreme degree

There's no limit to how much power you transmit; you can spray as many or as few photons as you like.  If you've got a kilowatt transmitter... or megawatt... gigawatt... terawatt... petawatt... no problem.  However, there is a limit to how sharply focused the beam can be, due to diffraction.  This is a function of the ratio between the wavelength of whatever you're sending (be it radio, microwaves, visible light, whatever) and the diameter of your transmission apparatus.  Discussion here.  For a circular aperture, the best you can do is a half-angle spread in radians equal to 1.22 times the wavelength, divided by the diameter.

That said, if we're talking a distance of 3000 light years, I think that's doable with current technology and engineering.  I forget the exact numbers, but I seem to recall reading that if we used the Arecibo telescope to transmit a message directly at another Arecibo-equivalent telescope pointed right at us, the max range would be something significantly bigger than that.

40 minutes ago, wumpus said:

We've seen *a star* at something like 13 light years.

...did you leave out some zeroes somewhere?  We've seen stars a whole lot farther than that. 

40 minutes ago, wumpus said:

send the information across the Schwarzschild radius

^ I think that complete inability to send any information across it is kind of what the Schwartzchild radius is about....

40 minutes ago, wumpus said:

The whole point of this is that "merely very difficult" might require physical and mathematical limits to require some vast amount of energy and power (you don't necessarily need the power, just expect to need more energy over time than if you used a lot of power) to simply send one bit.

Yes, but I don't think 3000 light years is all that un-doable.  That's a small percentage of the width of the galaxy, and my impression is that two Arecibos pointed at each other could communicate across that distance.  They'd have to be kinda patient, of course, but I don't think anyone's proposing this as a Netflix subscription mechanism. 

*rummage*

*rummage*

Ah, here we go.  http://www.setileague.org/articles/oseti.htm

Even the pessimistic estimate in this paper gives a communication range between two Arecibos as being on the order of 10,000 light years.  The optimistic estimate is 26,000.

So yeah, 3000 seems doable.

[WinkAllKerb'']

Δ(?x?) are sometime localised & observable, weirdly

that not exactly the first science field where it apply, then come the distance from here concern

it's kinda like saying: "all advanced enough technolgy could be called magic" sort off

[wumpus]

1 hour ago, Snark said:

There's no limit to how much power you transmit; you can spray as many or as few photons as you like.  If you've got a kilowatt transmitter... or megawatt... gigawatt... terawatt... petawatt... no problem.  However, there is a limit to how sharply focused the beam can be, due to diffraction.  This is a function of the ratio between the wavelength of whatever you're sending (be it radio, microwaves, visible light, whatever) and the diameter of your transmission apparatus.  Discussion here.  For a circular aperture, the best you can do is a half-angle spread in radians equal to 1.22 times the wavelength, divided by the diameter.

That said, if we're talking a distance of 3000 light years, I think that's doable with current technology and engineering.  I forget the exact numbers, but I seem to recall reading that if we used the Arecibo telescope to transmit a message directly at another Arecibo-equivalent telescope pointed right at us, the max range would be something significantly bigger than that.

...did you leave out some zeroes somewhere?  We've seen stars a whole lot farther than that.   whoops,  left out a 'billion' light years.

^ I think that complete inability to send any information across it is kind of what the Schwartzchild radius is about....

Yes, but I don't think 3000 light years is all that un-doable.  That's a small percentage of the width of the galaxy, and my impression is that two Arecibos pointed at each other could communicate across that distance.  They'd have to be kinda patient, of course, but I don't think anyone's proposing this as a Netflix subscription mechanism. 

*rummage*

*rummage*

Ah, here we go.  http://www.setileague.org/articles/oseti.htm

Even the pessimistic estimate in this paper gives a communication range between two Arecibos as being on the order of 10,000 light years.  The optimistic estimate is 26,000.

So yeah, 3000 seems doable.

 

I'd expect you can send a message *to* a black hole.  The big question is if any of the entropy is returned when/if the black hole decays.

Looks like the nearest black hole is 1,600 light years.  So a 3000 light year range should be enough.  But as I noted, you aren't going to be transmitting much to your black hole (probably the classic prime number sequence).  The text refers to a 1Hz signal.  So if your target understood all your modulation techniques (maximum transmission is indistinguishable from pure noise unless you know the exact decoding sequence) you might get a 1bs signal.  That's 1 bit per second, about 1/56,000 less than dialup.  Don't expect to be downloading any starship plans.

http://curious.astro.cornell.edu/about-us/88-the-universe/black-holes-and-quasars/observation-of-black-holes/452-where-is-the-nearest-black-hole-intermediate
 

 

[YNM]

Didn't see this (really I didn't see them previously despite just before my post) :

9 hours ago, jonnyL said:

Thankyou both for your quick response. As you may tell this certainly isn't my area of expertise, but I am looking for a solution whereby I could 'transmit' a data signal containing video (so several gb) 'into' a black hole- that is, directly 'at it'.

The premise of the idea is two fold. If i know from where it was sent, at what time and at where it was going;  I create in theory a digital timecapsule that can be 'unlocked' using any mobile device in the future.

The idea of this data travelling towards a black hole then also has the potential to be 'received' and intercepted by another form of intelligence.

To be clear and to summarise, this would be for a brand activation event. For this brand, I'd like to explore the reality of transmitting a data (video) package towards a black hole, and have a degree of certainty that some of this data would reach its destination, 3000 light years away. I'm looking for a solution to this problem, if you or anyone could help me. I'd need to know how to physically do this. 

Anyone interested?

Well, first of all, you (someone) have the initial 3000 yrs to fetch the data back. It's impossible for the whole beam to be absorbed into the thing, so anyone behind them would see lensing effects. I... forgot the calculation but presumably everyone behind them would also receive the signal, either "straight", or with echos at some points/line. Again, quite pointless IMO.

Tell your superiors that it would not be the best humanity have ever done. Think something else.

[Snark]

2 hours ago, wumpus said:

The big question is if any of the entropy is returned when/if the black hole decays.

You send energy in, you get totally random stuff out when it decays.  If the energy you send in is modulated-- i.e., data-- then that's just gone.  It's not as though the black hole remembers what the data was.

2 hours ago, wumpus said:

That's 1 bit per second, about 1/56,000 less than dialup.  Don't expect to be downloading any starship plans.

Oh, I dunno.  Given that the signal takes 1600 years to cross the distance anyway, it's probably okay if the message itself takes a decade or two to complete. 

[WinkAllKerb'']

the gps network was pointless , then it happenned, but true a satelite alone around don't help much ²+²

Edited July 25, 2017 by WinkAllKerb''