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How To Communicate Faster-Than-Light
higuita writes "With faster technologies showing up everyday, people need to prepare in advance the problems of faster-than-light communication. The main problem is that packages will arrive to the destination before they are sent, forcing a huge redesign of most protocols. Read here the first draft RFC. Any network expert is free to help fine tune this draft."
Is there some tradition in some parts of the world to make an ass of oneself on the second of April too?
When Argumentum ad Hominem falls short, try Argumentum ad Matrem
A double dose of April Fools?
Please Shoot Me In The Face Now! Several Times.
That's pretty cool. Of course, I knew about this post yesterday, before you'd even thought about writing it up on Slashdot. I'm not exactly how that worked, but thinking too hard on it makes my head hurt. I think I'll go lie down for a while and hope the future catches up with the past or something weird like that.
A truly excellent pizza parlor is a delight unto the heavens. Treasure the sauce and the toppings!
But I read this article first on Slashdot today and I thought that this might actually be somewhat based on real theory, until I read the article.
Maybe I'm too much into Star Trek, but I have to think there's a way to cheat(or at least bend) the speed-of-light limitations. I was interested in how they would deal with potential clock issues.. but bah.. April 1 got me. :(
OK, I know it's April fools, but why would a packet traveling faster than the speed of light necessarily arrive before it is sent? Do bullets shot faster than the speed of sound arrive before the gun makes a sound? No, it just arrives before the sound does.
It's perfectly obvious that this is true. However, it actually isn't true at all.
Relativity is a mind fuck.
I think we should just use FTL to request the RFC in its future state.
Hacker Evoution (http://www.hackerevolutionduality.com/) game.. anyone?
nothing faster, light can't hold a photon next to it.
Fuck systemd. Fuck Redhat. Fuck Soylent, too. Wait, scratch the last one.
It seems that the video game has appeared in the Steam Online store before a method has been devised to download it.
http://store.steampowered.com/app/212680
Just how recursive is this issue?
When people ask if I'm an optimist, I say "I hope so". --Bill Bailey
The info will arrive close to or near instantaneous the faster it travels
But that's not actually how it would work.
(looks at calendar) It's halfway through 2 April here.
We're WAY over the April Fool's thing.
In fact you will need to get your packets arriving before they are sent if you want April Fool's jokes to arrive here on time.
I am anarch of all I survey.
God would never let this happen
He let George Bush Jr. happen. He let Carrot Top Happen. He let Paris Hilton happen... you my friend are buggered!
we all know you arrive in the states before you leave Japan... and we've had subspace communication since the 60's (I saw it on TV). don't skip drones pretty much make this moot anyway?
what's the problem?
... how this is still an april fool's joke without having to click thru the poxy ROT-whatever 'encryption'
Remember kids: What's right isn't as important as what's profitable.
hey, Thanks! That's a really great link, and I like the illustrations about the "relative now" diagonal lines for each frame of reference.
Relativity is a mind fuck.
I think ...
you're holding it wrong.
--
"It is now safe to switch off your computer."
Okay, smarty. One quantum particle occupies 2 places in space at the same time (aka quantum entangled). You move them a lightyear apart then spin one. What happens to the "other" particle and when?
There is no causality when it's actually the same particle. The cause and effect are both that it is the same particle.
You do know people have free will, right? We can make choices and stuff.
Okay, I see a lot of people focusing on photons being used. But what about an FTL carrier pigeon? Or a carrier pigeon released from an FTL craft? I refer you to RFC 1149.
The overseas reporter delay shouldn't even really be happening anymore. I routinely make voice and video calls spanning 8 time zones with no noticeable delay.
Too bad you can't actually communicate with quantum entanglement, huh?
The most basic variant of quantum entanglement is two particles have opposite states (they could be photons with different polarizations, for instance) which are entangled. When one particle takes a state, the other particle takes the opposite state instantaneously.
The problem's that in order to make a particle "take" a state, we have to measure it. Measuring the particle will collapse the particle's wavefunction into one of its two possible states, but we can't select which. Hence, the particle will randomly take one state, and its paired particle the other. Since the selection is random, no information is gained.
Now, you say, we could just look for a state change in the particle! How? "Looking" for a state change involves measuring the particle, which collapses it, thus destroying the entanglement. We can't have a before/after check. Again, no information is gained.
With that said, entanglement still allows some pretty spiffy stuff, just not general purpose communication. One such example is called "quantum pseudo-telepathy", and it's one of the closest things to FTL communications we know of, allowing impressively high success rates at certain games for two players unable to communicate with one another in traditional ways. Note however that this doesn't allow to communicate so much as it allows for certain probabilistic events to be skewed.
From your link
Getting a message after it was sent is no biggie. I mean; write yourself a letter if you want to see that in action. But getting a message before it was sent causes issues (see for example; practically every sci-fi franchise). What those issues are exactly depends on how time travel works (e.g., "Timecop" or "Back to the Future" rules?), and thatâ(TM)s wide open to debate.
Flash forward 250 years to a physics class.
"So as we've learned in 2100 scientists discovered it was possible to communicated instantaneously"
"But Miss, doesn't that mean causality violations?"
"No of course not, as I mentioned we now know the multiverse works according to the 'Sliders' rules "
echo -e 'global _start\n _start:\n mov eax, 2\n int 80h\n jmp _start' > a.asm; nasm a.asm -f elf; ld a.o -o a;
You do know people have free will, right? We can make choices and stuff.
One choice you simply don't have is to communicate information faster than light. Who or why that is the case may be due to God, which is sort of the point being made by the GP. There is no negative proof of this idea, but there isn't a positive proof either. Stephen Hawking has spent some time discussing what God may or may not have done in terms of setting up the universe as we know it, but there certainly seems at the moment to be some arbitrariness to some aspects of the universe as we see it. One of those is how the speed of light was established and why that particular speed is what we see it to be. Ditto for the Plank constant and a few other interesting aspects of the universe.
If we at least consider that current theories do have the speed of light in vacuum as a limit it is still possible to exceed the speed of light in other materials like glass and water.
But even if you exceed the speed of light it doesn't mean that the event is observed before it happens. It just means that you get notified about the event faster than expected.
There are also some phenomena that are a bit on the border of being tricky to explain given the theories of today, but they are usually on a small scale involving quantum mechanics - like teleportation of particles. And even the current theories offers "loopholes" for exceeding the speed of light - like spacetime warping and wormholes.
If builders built buildings the way programmers wrote programs, then the first woodpecker would destroy civilization.
There still is a delay of some sort, even if you aren't noticing it. The deal with the "delay" was usually due to sending signals to geosynchronous orbit satellites. At 35,000 kilometers, the time to send a signal to those satellites and have it return is sufficient that somebody with a stopwatch controlled by people is enough to even measure.
In fact a really interesting experiment used to be performed where you could take something like a State of the Union address, and for those stations that used satellite transmission could be compared to stations that used microwave relay stations, and the time interval from when something was seen on one station compared to the other (assuming no tape delay issues) could be used to measure the speed of light.
What you are noticing here is that the digital traffic signals and even phone conversations don't use satellite links any more, but rather fiber optic cables that are either buried or placed at the bottom of oceans. Either way, signals only going a couple megameters as opposed to over 70 megameters in distance adds up to a significant change in perception of delay due to the speed of light.
Even if quantum entanglement worked that way (it doesn't; that's just the most palatable way to present a concept that's too weird to understand without years of intense study), that doesn't change the facts. Relativity still means FTL communications would violate causality if they were possible.
It's perfectly obvious that this is true. However, it actually isn't true at all.
Relativity is a mind fuck.
Maybe I'm punting the brain fuck, but this makes time a weakly-ordered sequence. For instance, a 100ms ping means that "now" lasts 100ms. If I get an answer after 50ms, we say that it has travelled back in time.
Or maybe it's the theory of relativity that says that, in the same way that a binomial equation might have a negative impossible solution. Now is that theory valid outside its scope? Was Newton's?
If we manage to get 10c FTL, then our definition of "now" will become 10x shorter and nothing more will come off it. If we manage to get -1c FTL, our definition of "now" becomes a recursive "always" and we'll get some Steins;Gate snafu.
tl;dr
Instantaneous communication can means different things because "now" has a duration. For your martian pal, "now" means 10 minutes ago, but "now" also means 10 minutes in the future. You can play games with those extremes.
ID: the nose did not occur naturally, how would we wear glasses otherwise? (apologies to Voltaire)
When we have FTL communication in which packets arrive before they are sent, I will have written the needed protocols in 2010. I'll start them in 2016, complete them in 2010, and finish compatibilty testing in 2009. That'll let Microsoft implement them in 2057.
Ignorance admitted to...
I would argue that all the theories proposing this time reversal have also stated that you can't send the information faster then light. So... assuming we are sending the information faster then light, why would we think the rules that say we can't still apply?
The only way you get FTL communication is if we find some loophole in the laws that lets us slip information IGNORING the very law that supposedly would cause things to time travel.
That being the case, we can't really assume how the information will travel. Possibly it would be instantaneous communication. That is, information arriving WHEN it is sent not before or after.. but precisely WHEN it is sent.
That said, so far as I understand we have no means of FTL anything. Apparently even gravity moves at the speed of light which is sort of depressing. I read a fair amount of science fiction and it was assumed in much of it that gravity "waves" could be used to communicate FTL... well, according to some scientific publications I skim they go at the speed of light. What goes faster then light? I don't know... tachyons? Again, I think I've learned everything I know about tachyons from "fiction"... so I don't really know anything about them besides that they're supposedly unable to travel slower then light and time travel and possibly some other fun stuff.
Whatever... have fun with any of the above systems because they all look equally fruitless.
I'd love FTL communication. We do need it or something like it especially as we try to manage our legions of drones exploring the solar system. But until we have such a system I see no point in theory crafting the protocol it would use. You might as well pick out the sofa coffee table arrangement for your working model of the starship enterprise... complete with teleporter and holodeck... which will be used exclusively for naked orgies with holo-porn... because that's what you do with holodecks.
Anyway, I have no idea what I'm talking about but I suspect everyone is talking out of their asses on this one so at least I'm not alone on it.
I've decided to stop wasting my time responding to AC trolls/sockpuppets... so if you want a response from me... login.
... the result still looks like gibberish.
What gives?
Il n'y a pas de Planet B.
It can be done anywhere in the universe. My guess is in the future when we master an electron moving in a carrier wave entangled to another electron we will have instant communication.
http://saveie6.com/
I can explain dimensions 4 through 10(or even 11...maybe) to people, but I can't understand those diagrams. Didn't anyone ever teach that scientist to label his axes? Jeez.
If the only way you can accept an assertion is by faith, then you are conceding that it can't be taken on its own merits
I think we should parse what we mean by FTL communication carefully there are some possibilities that don't require changes to TCP detailed in RFC 6921.
First we have schemes like EVE online fluid routers which hack entanglement to communicate instantaneously between routers. There is no backwards time travel here.
Second we have wormholes or warp capable ships loaded with tape drives. There is also no backwards time travel here as you are taking shortcuts thru stretched space rather than locally exceeding c.
Third we have to think about what we mean by communications... If you are in a space ship traveling to the nearest star and you are going 99.9999...% the speed of light the 4 ly journy might only seem to you to take a few minutes if you throw in enough 9's. Once you arrive you can carry out normal delay tolerant IP exchanges without ever having to wait 4 years to communicate with the reciving party however they would have waited about 4 years to communicate with you.
Finally we have tachyons which propogate superluminally with reversed cause and effect. This is the only scheme of the bunch that requires RFC 6921.
I think the simplest solution to this entire mess is that relativity is not always correct. There are already certain areas of physics and sciences where relativity breaks down at certain points.
Progress and scientific advancement means adapting existing theories to encompass new discoveries: until we actually can use something like this, it's all theoretical.
If the only way you can accept an assertion is by faith, then you are conceding that it can't be taken on its own merits
April fools i know but, The Speed of Light is simply that, a recognised speed. If I was travelling 10 light seconds at twice the SOL, I would get there in around 5 secs depending on massive magnetic interference. Something could not arrive b4 it's sent, a tiny fraction over 0 yes. I don't believe travelling at the SOL slows time, mearly presents a huge issue where hitting a tiny particle would be a disaster xD the forces involved would be insane. I could also be wrong but prove it!
I don't get it. Why do physicists use GR for FTL? That does not make sense. It is the same as using Newtonian physic for relativistic speeds. GR was not designed for FTL, obviously.
All of the examples of violating causality is based on defining "now" in two different frame of reference. However, this "now" is established using GR while the "signal" (or bullet or whatever) uses FTL. That does not make sense.
If you have FTL you use FTL for everything including determining "now". Of course, you need new physic to do that. However, disproving FTL with GR is pointless using these examples.
Instead, why not use the curvature of space for disproving FTL?
Every particle travels through space, even the photon. According to GR space itself also changes with the speed of light. This means space itself cannot react fast enough for an FTL particle. It would be similar as if a ship did not disturb the water as it passes. And that is impossible.
Government cannot make man richer, but it can make him poorer. - Ludwig von Mises
A digital fountain emits a stream of packets, consisting of a packet number, which selects a pseudo-random set of pieces of a file to be sent all XORED together. If you collect enough packets, no matter what order, you can derive the whole file (using Gaussian elimination to un-XOR it). Put everything you want to send to the past into a huge ZIP file, then use a digital fountain to send it, and it get there eventually, no matter what the time shift involved.
In the many worlds paradigm, all the outcomes that can happen do and become branching points for new possible universes that coexist in parallel in the light cone. So the path you walk may be deterministic inside an infinite number of parallel outcomes and in that context free will is alive and well.
ack
ack,syn
syn
open
My ism, it's full of beliefs.
A packet can't arrive before it's sent, If it could then in theory it would be possible to have communication without a source.
I can send one bit of communication faster than light. All I need is really long stick. *poke* *poke*
"Evil will always triumph over good, because good is dumb." - Dark Helmet (Spaceballs)
Uhhh, April first was YESTERDAY.
Oh, wait! I see what you mean! This post went back in time and really appeared yesterday!
Good show.
rgb
Even when the experts all agree, they may well be mistaken. --- Bertrand Russell.
I'm not sure what it is that you're trying to say, but I'm pretty sure you're not correct.
What Einstein taught us about time and space is that you *cannot* go faster than light. Pushing something up to the speed of light would take an infinite amount of energy. However, if you *could* go faster than light, it would allow you to leave a point at a certain time, and then return to that same point in space at a time earlier than when you left. If you could send a message faster than light, and the recipient could respond with a faster-than-light response, then you could receive the response before you send the message.
Maybe you should understand it before trying to make exceptions?
In an overly simply nutshell. It's random and uncontrollable. You have no way of influencing or knowing in advance which way it will flip.
As such, you can't send information.
The Kruger Dunning explains most post on
I'm wrong about the instantaneous communication bit. Instantaneous communication could cause observers to have messages arriving before they were sent.
It really depends on how information travels thru space. If instantaneous communication method does not *propogate* thru 8 light minutes distance of space then there is no inverting of cause and effect in any reference frame.
It is only if the information has to propogate thru space using a method locally exceeding c that these weird reversals of cause and effect would occur.
Quantum Entanglement would permit FTL communications.
Does anyone read science news these days?
Didn't they already solve the "measuring it destroys it problem" by measuring quantum particles it in a certain way that didn't disrupt them and used that to make a working qubit and make a working 16-gate (or whatever) quantum CPU and do math on it and it worked? The answer is yet, by the way. And it was on slashdot :-P
This isn't the first comment along these lines I've seen in the comments section. Dear god, has the level of science education on /. really fallen this low, or am I being pranked by belated April-foolsers?
Sending a message back in time from your own perspective does require bouncing it back from a moving reference frame to my knowledge, but is a valid consequence of FTL communication within special relativity.
Stop assuming you already know everything and can dismiss anything you don't understand; it just makes you look stupid. You don't appear to have even heard of special relativity beyond the word "observer", so I'm not sure why you think you can overturn the work of pretty much every physicist who's looked at the subject beyond unwarranted hubris.
Thats how Bill S Preston, esq was able to hide his fathers keys in that bush in front of the police station
Sometimes, life itself is sarcasm...
Editors can go into the future and fetch news that isn't quite so old.
Have gnu, will travel.
"spooky action at a distance"
Quoting from the same wikipedia article:
"The outcome of Alice's measurement is random. Alice cannot decide which state to collapse the composite system into, and therefore cannot transmit information to Bob by acting on her system. Causality is thus preserved, in this particular scheme. For the general argument, see no-communication theorem"
I think FTL communication is simple
This is ususally a good clue your understanding is incomplete.
setup spin detector aparatus, and ensure exact distances are known... then use a basic binary representation for spin=binary, and the instant action of the paired photon can be seen at the other end...
Now go try and develop a protocol which exchanges useful information this way.
Okay, smarty. One quantum particle occupies 2 places in space at the same time (aka quantum entangled). You move them a lightyear apart then spin one. What happens to the "other" particle and when?
There is no causality when it's actually the same particle. The cause and effect are both that it is the same particle.
1: It's not the same particle.
2: Information is not transferred, you don't get to spin one, you can merely read the spin of one and instantly know the spin of the other.
Imaging flipping a coin. You look at it as it lays on your hand or on the ground. You see the top and see that it's heads. You instantly know that the bottom is tails.
The information of the bottom being tails didn't arrive faster than light. You discerned it to be the opposite of the top before the experiment, and you learned of the top's state without violating the speed of light by looking at it. If you entangle particles and know the relation of their spins and then send them far apart, you're doing the same thing. Absolutely no information is transferred FTL.
It's called the "Girls' Gossip Group." Your girlfriend knows you cheated on her before you cheat on her.
Vote monkeys into Congress. They are cheaper and more trustworthy.
a caremel for the winner! - mod up!
Except in the real world the average person doesnt need the metric system. Units of measurement are just a way to be able to identify how far/big/much something is. I dont need to know how many feet are in 2.5 miles in order to estimate the distance of 2.5 miles. Hell, trying to visualize how many feet it is would just give someone a headache. I dont know the precise measurement of a horsepower but i know what 100hp does in a 3000 pound car. (not much). Its all about relativity to the user. Why do scientists use AU? An AU is just distance from sun to earth. Hardly metric. Same for a light year. Neither are metric yet are used all the time in the scientific community because you can quickly guesstimate distances that way.
https://en.wikipedia.org/wiki/Telepathy
Casteism
Because Clause 9 of the Roommate Agreement http://wiki.the-big-bang-theory.com/wiki/Roommate_Agreement would require them to advise each other.
There is nothing wrong with yr Internet. Do not attempt to adjust the picture. We are controlling the transmission - NSA