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Comment by pinkrooftop | Hacker News Reader

Would it be possible to listen for information transmitted via gravitational waves? Would there be any benefit over radio?

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The amount of energy needed to transmit via a gravitational wave is INSANE. It would involve very rapidly accelerating and decelerating a black hole / neutron star. While it might be possible to do this, it's not within the realm of something we could accomplish without several orders of magnitude technology improvements, and possibly may not be physically possible at all (moving object that heavy that quickly might require creating a black hole)--though I don't have the skill to prove or disprove that.

Even if it were possible, what sort of crazy alien would it take to burn 3 solar masses of negentropy to basically run a ping, compared to the amount of data that could be transmitted with electromagnetic waves with 3 solar masses of negentropy? It's literally dozens of orders of magnitude in difference. Any aliens that are that bad at engineering probably aren't going to grow to the point that they can shake neutron stars several times per second.

Our power generation stations are the black hole equivalent to the caveman with only access to generating fire through rubbing stones.

Based on what level of civilization you are. Rubbing two black holes in for a ping, might be the same as rubbing two stones for a spark. Advanced civilization go really advanced, to a point their activities would be undetectable to us or would appear to us the nature of reality itself.

"Advanced civilization go really advanced, to a point their activities would be undetectable to us or would appear to us the nature of reality itself."

This is science fiction, not an argument. We have no rational reason at the moment to believe this is the case, or even possible.

What we do in fact have is an increasing trend towards efficiency. Projecting that out along crazy growth curves suggests that advanced aliens are likely to be more horrified by such a waste of negentropy than we are. What can we do with that much negentropy? Nothing, basically. What can they do? Simulate many millions/billions/whoknows of human-level civilizations?

They're not more likely to be indifferent about such waste, they're more likely to prosecute you, for mass civilizational murder.

I've often thought that if civilization could advance to that point in the future, that I'd have a difficult time explaining to my great-great-great-X grandchildren that when ol' great-great-great-X-grandpa was young, you know, pouring a tank of gasoline into the car got me from point A to point B and that was it, despite it being enough energy in that one tank of gas to, say, simulate an entire human's life time. Well, kids, we didn't have that option! The tech didn't exist. So stop trying to put ol' Greats on trial for things he couldn't control, OK?

>>This is science fiction, not an argument. We have no rational reason at the moment to believe this is the case, or even possible.

There are not only rational reasons, but even evidences to support what I'm trying to say.

Look at any insect colony or bacteria, they don't even recognize our presence, let alone our technology.

>>What we do in fact have is an increasing trend towards efficiency. Projecting that out along crazy growth curves suggests that advanced aliens are likely to be more horrified by such a waste of negentropy than we are.

We the advanced aliens to ants, are indulging waste and plastic pollution like never before. And ants the aliens to bacteria might appear the same.

Efficiency and waste are very relative terms based on what level of abundance or austerity on is supposed to live on.

This event was the equivalent of three of our suns turned into pure energy. Pretty expensive to send a message.

Burning a few suns per message would significantly reduce spam.

Your post advocates a

( ) technical ( ) legislative ( ) market-based ( ) vigilante (X) Physics-based

approach to fighting spam. Your idea will not work. Here is why it won't work. (One or more of the following may apply to your particular idea, and it may have other flaws which used to vary from state to state before a bad federal law was passed.)

(X) The amount of energy involved would likely destroy the planet.

(X) Many email users cannot afford to lose business or alienate potential employers

Specifically, your plan fails to account for

(X) The relative sparseness of non-dark energy in our vicinity

(X) Huge existing software investment in SMTP

and the following philosophical objections may also apply:

(X) Incompatiblity with open source or open source licenses

(X) I don't want the government reading my email

Furthermore, this is what I think about you:

(X) Sorry dude, but I don't think it would work.

(I'm sorry, but I couldn't resist)

Yeah, but that was for a message sent across a distance of ~1 billion light-years.

I naively assume that shorter distances would require less energy.

> This event was the equivalent of three of our suns turned into pure energy.

"The collision unleashed the energy of a billion trillion Suns in a fraction of a second."

That's the energy emitted by a billion trillion Suns. The total energy being equivalent to three Suns turned into pure energy.

> Would it be possible to listen for information transmitted via gravitational waves? Would there be any benefit over radio?

Well, if you observe a meaningful, non-natural gravity wave signal, you know that you've discovered not merely another technical situation (which you'd know if you detected the same thing in radio waves), but a phenomenally advanced one.

So, if not an advantage, there is at least a meaningful difference.

AFAIK that doesn't seem at all feasible yet. Currently you need an enormous facility, which struggles to detect anything but the most powerful gravitational waves.

I think if you really wanted to think outside of box for this, quantum entangled particles is your best bet for instantaneous low energy communication

You can't transmit information through entangled pairs. What is instantaneous is the change of the state for the whole system (the pair) after you measure one of particles. However the result of that measurement (if it's non-trivial, i.e. if the measurement actually changes the state) is fundamentally random so the only thing you would be seeing is perfectly and instantaneously correlated noise on both ends.

I'm sorry but no, you cannot transfer information with quantum entanglement. What entanglement says is that if you have a photon and I have a photon and they are entangled and you make a measurement on some attribute of your photon, my photon will assume the complimentary state. However, the state your photon assumes when you measure it is random and once you measure it, you lose the entanglement. So, there's no way for you to encode any information in your entangled photon. Yes, I can infer what state your photon was in as soon as you measure it, this is useful for encryption as we can then compare notes after making a measurement and make sure nobody tampered with our entangled photons.

No it isn't. Quantum entanglement doesn't allow for instantaneous communication[0][1].

[0]http://curious.astro.cornell.edu/about-us/137-physics/genera...

[1]https://physics.stackexchange.com/questions/78118/quantum-en...

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