B Gravitational waves for data communication?

[alan123hk]

When and how can the gravitational wave be used for data communication, which the speed be much faster than the current technology by means of electromagnetic wave like 5G, 6G..etc wireless systems ?

 

[LURCH]

Unfortunately, it takes an event with an enormous amount of energy (like two black holes colliding) to create ah gravitational wave that moves detection instruments 1/10,000 the size of an atomic nucleus. The best technology currently available requires 800 km of vacuum tubes and an equipment package worth more than the gross national product of most countries. Even then, it takes days of processing data to become “pretty sure” that a wave went by.

Given all of this, I don’t think that gravitational waves will ever be usable for data transfer.

 

[davenn]

Given all of this, I don’t think that gravitational waves will ever be usable for data transfer.

Agreed

When and how can the gravitational wave be used for data communication, which the speed be much faster than the current technology by means of electromagnetic wave like 5G, 6G..etc wireless systems ?

and gravitational waves DONT propagate faster than light ... therefore they don't propagate faster than radio waves

 

[mfb]

The strongest somewhat plausible source of gravitational waves we could build emits waves about a factor 1000000000000000 too weak to detect with a the best available detectors sitting right next to it - even if we ignore that the detector would be completely overwhelmed by the seismic activity of these sources (that is not what you want to measure).
Never say never, but it would surprise me if this becomes a useful method of data transfer. Certainly not in the foreseeable future. It wouldn't be much faster either. Both gravitational waves and electromagnetic waves travel at the speed of light. You can send signals through the Earth instead of around it, that is nice, but that is easier to do with neutrinos.

 

[alan123hk]

Unfortunately, it takes an event with an enormous amount of energy (like two black holes colliding) to create ah gravitational wave that moves detection instruments 1/10,000 the size of an atomic nucleus. The best technology currently available requires 800 km of vacuum tubes and an equipment package worth more than the gross national product of most countries. Even then, it takes days of processing data to become “pretty sure” that a wave went by. Given all of this, I don’t think that gravitational waves will ever be usable for data transfer.

Thank you for your clear explanation, I know that it's almost impossible to achieve the idea now.

and gravitational waves DONT propagate faster than light ... therefore they don't propagate faster than radio waves

Sorry, I didn't express myself clearly enough, actually I meant the upload/download speed, namely the data speed.
I just thought that there would be enormous potential bandwidth so that the data speed can be tremendously increased if the gravitational wave communication can be realized in the future.

 

[jbriggs444]

actually I meant the upload/download speed, namely the data speed.

That makes the problem even worse. Now we are not just interested in generating and receiving a signal at all, we need to generate and receive more rapidly than conventional broadcast, copper or fiber optic media.

What is the use case? Communications with space probes? Local area wireless broadcast (wifi)? Cellular telephone service? Wide area broadcast transmission (radio and TV)? Replacement for long haul data transmission cables? High speed communication within a central processing unit?

The ability to multiplex multiple signals by using strands and cables is a huge win for fiber optic media. It is not clear that there is any corresponding ability with gravitational waves. We'd likely be limited to broadcast.

 

[Vanadium 50]

I meant the upload/download speed, namely the data speed

Why do you think gravity wins over EM here?

 

[sophiecentaur]

Relative merits as a communication medium: A single channel with a data rate of perhaps 100b/s for gravitational waves doesn't compare favourably with an available EM spectral bandwidth of a couple of hundred THz and excellent possible directivity.

 

[alan123hk]

Why do you think gravity wins over EM here?

Because the electromagnetic spectrum is scarce resource, it has almost been occupied and used up by humans, on the other hand gravitational wave spectrum is still unoccupied.

Relative merits as a communication medium: A single channel with a data rate of perhaps 100b/s for gravitational waves doesn't compare favourably with an available EM spectral bandwidth of a couple of hundred THz and excellent possible directivity.

But it seems gravitational waves could exist at any frequency in principle, it looks like may be the rest of the problem is how to invent small size and high frequency gravitational transmitter and receiver.

I know this ideal maybe mission impossible today, but will it be happen in the distant future, such as hundreds or thousands of years from now ?

 

[LURCH]

Although gravitational waves will probably never be used as a data-carrying device, they may have a more indirect effect on information infrastructure. The mere fact that they exist, and have been observed, means that we now know of at least one type of wave that travels at light speed, and can pass through almost any obstruction with virtually no losses. The existence of one such wave brings up the possibility that there may be others. There’s no way to even speculate as to what those may be, but the properties themselves have been shown to exist, so perhaps they exist in some other phenomena that we have not yet thought of. Maybe even one that might be usable by us, in the distant future.

 

[russ_watters]

Because the electromagnetic spectrum is scarce resource, it has almost been occupied and used up by humans, on the other hand gravitational wave spectrum is still unoccupied.

That doesn't really properly address @Vanadium 50 's question. In your first post, you said faster, which should mean it has more inherent capacity, which it almost certainly does not. Perhaps more important, gravitational wave communication would be omnidirectional and un-containable, making interference between transmissions a bigger problem.

Anyway, I think this is all moot because it doesn't appear to me that such communication will ever be feasible at all.

 

[alan123hk]

That doesn't really properly address @Vanadium 50 's question. In your first post, you said faster, which should mean it has more inherent capacity, which it almost certainly does not. Perhaps more important, gravitational wave communication would be omnidirectional and un-containable, making interference between transmissions a bigger problem.
Anyway, I think this is all moot because it doesn't appear to me that such communication will ever be feasible at all.

It's not that gravitational wave has more inherent capacity so it is superior to EM wave, I mean because gravitational wave spectrum is still unoccupied, therefore, we can increase the data rate almost unlimitedly for a communication channel by means of increasing its channel bandwidth, which is based on the basic digital communication theory.

Yes, gravitational wave communication would be omnidirectional, but this still has merit in certain application like broadcasting.

I agree that this discussion may be meaningless and will not lead to any satisfactory conclusions, but I still beg for not banning this thread.
Anyway, history tells us that things are impossible today may become possible in the future.

 

[Vanadium 50]

gravitational wave spectrum is still unoccupied

One could make the same argument about carrier pigeons.

therefore, we can increase the data rate almost unlimitedly for a communication channel

Nonsense. This doesn't work for carrier pigeons.

I agree that this discussion may be meaningless

If so, whose fault is that?

 

[PeterDonis]

@alan123hk please do not use blue for the text of your posts. It makes them harder to read.

 

[nsaspook]

Although gravitational waves will probably never be used as a data-carrying device, they may have a more indirect effect on information infrastructure. The mere fact that they exist, and have been observed, means that we now know of at least one type of wave that travels at light speed, and can pass through almost any obstruction with virtually no losses. The existence of one such wave brings up the possibility that there may be others. There’s no way to even speculate as to what those may be, but the properties themselves have been shown to exist, so perhaps they exist in some other phenomena that we have not yet thought of. Maybe even one that might be usable by us, in the distant future.

We could use neutrinos for much the same effect. It's really difficult but maybe not really, really, really difficult like gravitational waves.
https://physicsworld.com/a/neutrino-based-communication-is-a-first/

 

[m4r35n357]

Perhaps more important, gravitational wave communication would be omnidirectional and un-containable, making interference between transmissions a bigger problem.

If I remember correctly (I haven't worked it out myself, that is above my pay grade!), gravitational wave propagation falls away faster than $distance^2$, so from a purely engineering (cellular) perspective this property would be an advantage ;)
I think maybe a stronger argument against GW communications is that the transmitter and receiver are essentially the same thing (directly coupled mass systems), so bidirectionality would be a bit of a problem!

 

[mfb]

@m4r35n357: The intensity drops with an inverse square law (it has to, conservation of energy) but the amplitude, what we measure, drops with 1/r only.
Transmitter and receiver are completely different objects for gravitational waves. One needs large changes in the quadrupole moment (huge masses whirling around), one needs to be as motionless as possible to detect tiny length changes.

 

[m4r35n357]

@m4r35n357: The intensity drops with an inverse square law (it has to, conservation of energy) but the amplitude, what we measure, drops with 1/r only.
Transmitter and receiver are completely different objects for gravitational waves. One needs large changes in the quadrupole moment (huge masses whirling around), one needs to be as motionless as possible to detect tiny length changes.

OK I can't find a reference for my first "claim". However, the second is a little less subtle, if you address the bidirectionality part ;)

 

[mfb]

However, the second is a little less subtle, if you address the bidirectionality part ;)

What is there to address? Significant emitters of gravitational waves have nothing in common with sensitive detectors of gravitational waves. Everything that emits any relevant amount of gravitational waves is a horrible detector for them.

 

[m4r35n357]

What is there to address? Significant emitters of gravitational waves have nothing in common with sensitive detectors of gravitational waves. Everything that emits any relevant amount of gravitational waves is a horrible detector for them.

I was just making a point about the practicality of bidirectional communications, and you obviously missed it! Never mind . . .

 

[davenn]

I was just making a point about the practicality of bidirectional communications, and you obviously missed it! Never mind . . .

and you missed the point being made that it isn't practical

 

[m4r35n357]

and you missed the point being made that it isn't practical

No. I did not. I was making that point.
[EDIT]
OK, I'll bite. In a former existence I used to design balanced duplex radio links, so I remember what crosstalk and isolation are. I also know what signal delay is.
So, for a two way comms link we have a transmitter (lets say a binary neutron star) and a receiver (a sensitive interferometer) in close proximity . . . hmmm what could possibly go wrong?
To make things a bit more tricky, we need to wiggle the neutron stars to modulate our signal, easy huh?
Oh, and signal delays (many human lifetimes) over long distances, and we can't do mobile very easily either, and we' have to operate the whole thing from a remote distance.

 

[Klystron]

This thread is reminiscent of a thread on a different forum that suggested improving electron microscope resolution by replacing electrons with 'a smaller charged particle'; to wit, quarks. Confinement and the strong force among other issues convinced the OP that 'loose quarks' do not an electron make and the OP also learned about tunneling electron microscopes.

For communication purposes gravity waves would seem to suffer from the opposite problem: gravity is proportionately so much weaker than EM. Modulation to carry signal implies control of gravity at least as developed as electronics was say when vacuum tube amplifiers were invented?

 

[nsaspook]

This thread is reminiscent of a thread on a different forum that suggested improving electron microscope resolution by replacing electrons with 'a smaller charged particle'; to wit, quarks. Confinement and the strong force among other issues convinced the OP that 'loose quarks' do not an electron make and the OP also learned about tunneling electron microscopes.

For communication purposes gravity waves would seem to suffer from the opposite problem: gravity is proportionately so much weaker than EM. Modulation to carry signal implies control of gravity at least as developed as electronics was say when vacuum tube amplifiers were invented?

Vacuum tubes would be advanced technology. Today we are not even at the spark-gap phase of possible gravity communication.