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Wormholes and entanglement

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Arenamontanus Arenamontanus's picture
Wormholes and entanglement
Some new theoretical physics: maybe entanglement actually is wormholes. http://johncarlosbaez.wordpress.com/2014/01/20/wormholes-and-entanglement/ http://golem.ph.utexas.edu/category/2014/01/wormholes_and_entanglement.html http://quantumfrontiers.com/2013/06/07/entanglement-wormholes/ The basic idea is that entangled particle pairs are actually connected by wormholes. John Baez develops this in a 2+1 dimensional universe (no guarantee this applies to *our* universe). For EP, this might actually be a nifty way of explaining what QE comms is doing: qubit pairs actually communicate using tiny wormholes, too tiny for any transport but still allowing communication... with its associated bizarre time communication implications of course. But we already had the potential of time machines with the Gates in any case. No doubt everybody has been working hard on turning qubits into gates or sending more than one bit per qubit hole, but that tech has so far eluded transhumanity. The real Gates are presumably using wormholes to transport stuff, but the wormholes may themselves just be stored as packages of qubit-pairs (and maybe they are just matter disassemblers/assemblers and send information instead). "Fake entanglement" which shows up in the above theory might also explain why gates can dial each other directly. This is of course mostly flavor, but it is consistent flavor. And the papers linked above can give some nice technobabble. "The gate engineer is complaining that he can't get the 2-functors to commute this morning, so you have to go via Portal."
Extropian
thezombiekat thezombiekat's picture
a while ago i did some maths
a while ago i did some maths on getting more than one bit out of a qbit with no new science. basically if you have 2^n entangled particles, each numbered and representing an unsigned integer you can send n bits by expending a single entangled particle. before sending the next signal you have to replace the entangled particle you used, so you need some spare entangled particles. thus for doubling the number of entangled particles you have you quadrupedal the amount of data you can send. of cause when we observe that the large packet costs 4 times as much as the small while giving 10 times the data transfer we must assume the system is already in place and the difference in price is due to system efficiency.by extension if you buy enough qbits you can get very cheep data transfer.
Arenamontanus Arenamontanus's picture
thezombiekat wrote:basically
thezombiekat wrote:
basically if you have 2^n entangled particles, each numbered and representing an unsigned integer you can send n bits by expending a single entangled particle. before sending the next signal you have to replace the entangled particle you used, so you need some spare entangled particles.
How did you calculate this? If you expend one of them, all of the entanglement is broken.
Extropian
thezombiekat thezombiekat's picture
why would entanglement be
why would entanglement be broken on any particle other than the one activated. working on a small n of 4 to illustrate line up 16 entangled particles and number each one starting at 0 and going to 15, some effort is involved during manufacturing to ensure the particles are correctly numbered in each unit. the first 4 bits in the file are 0100 if taken as an unsigned integer this is 4 so the sender excites particle 4, this excites the receivers particle 4 which is detected, the receiver knows that 4 is represented in 4 binary digits as 0100 so that is what it outs in the file. doing that decoupled particle 4 but should have no effect on other particles. the first spare particle is given the number 4 and your set to send another 4 bits. naturally nobody would bother building a n=4 device. assuming 1080p 25FPS and 256 colors stored in bit map style with no compression (all probably wrong by EP time) the listed Q bit reservoirs small 10 hours vidio is probably an N=18 device and the large 100hours vidio would be an N=20 device.
Arenamontanus Arenamontanus's picture
thezombiekat wrote:why would
thezombiekat wrote:
why would entanglement be broken on any particle other than the one activated.
Ah, the the particles sent are entangled with paired particles at home. I thought you meant a n-way entanglement. My bad.
Quote:
working on a small n of 4 to illustrate line up 16 entangled particles and number each one starting at 0 and going to 15, some effort is involved during manufacturing to ensure the particles are correctly numbered in each unit. the first 4 bits in the file are 0100 if taken as an unsigned integer this is 4 so the sender excites particle 4, this excites the receivers particle 4 which is detected, the receiver knows that 4 is represented in 4 binary digits as 0100 so that is what it outs in the file. doing that decoupled particle 4 but should have no effect on other particles. the first spare particle is given the number 4 and your set to send another 4 bits.
This is where things don't work. How do you tell if particle k is excited? You measure it. You cannot look at the all the particles (that is a measurement) and then just measure the excited one. At best you measure particle 0, particle 1, particle 2, and so on until you hit the excited one. At that point you will on average break entanglement of half of them. So now you have expended 8 qubits to send one classical bit. (There might be a way of doing it using 4 wasted qubits using the Grover quantum search algorithm, but I am not sure it works)
Extropian
thezombiekat thezombiekat's picture
An interesting point. I don’t
An interesting point. I don’t suppose indirect observation would help. Measure the energy of the particle next to the entangled particle. We need never know exactly how energised it is, just that the state changed. Exactly what constitutes observation in quantum mechanics anyway? I have a list of experiments I would like to perform with cameras that are and are not connected to storage media that may be destroyed without being looked at. Of cause this would also be a problem for 1 bit per particle systems. The receiver needs to observe a particle to know it is not being sent a signal. Now it could make the observations only occasionally and sped up observations when it is getting a signal but it does introduce a shelf life to the units. A century of inactivity is the same as an hour’s video. Another idea for transferring more data occurred. If your sending 1 bit per particle you need 3 states (ground=no signal, one, zero) if you define more discreet energy states you can transfer more information. With 8 non ground states you could transfer 3 bits per particle.
Smokeskin Smokeskin's picture
thezombiekat wrote:An
thezombiekat wrote:
An interesting point. I don’t suppose indirect observation would help. Measure the energy of the particle next to the entangled particle. We need never know exactly how energised it is, just that the state changed. Exactly what constitutes observation in quantum mechanics anyway? I have a list of experiments I would like to perform with cameras that are and are not connected to storage media that may be destroyed without being looked at.
Interaction with anything is observation. If the photons or whatever that interact with the superpositioned particles end up hitting cameras, storage media, conscious observers, or just flying off into deep space never to be seen by anyone, it is still observation. Don't read too much into the Copenhagen interpretation.
thezombiekat thezombiekat's picture
but if any interaction with
but if any interaction with another particle (or as withe the flying into deep space example, not interacting) counts as an observation, how do you store a pair of quantum entangled particles without having them "observed" by the walls of the container they are in and thus breaking the entanglement.
Smokeskin Smokeskin's picture
As I understand it, you have
As I understand it (and at best I have a popular science level insight), you have a property - say the spin - that you want to keep in a superposition, and then you manipulate the particles in ways that don't affect the spin. In any case, it doesn't make an ounce of difference if you store the observation result or not, or if anyone finds out about. It is the most basic part of the measurement that matters, that initial interaction that "measures" the state.
Chernoborg Chernoborg's picture
Thinking about it in setting,
Thinking about it in setting, would this interfere with sending qubit coms through the gates? Running a wormhole through a wormhole seems like it would bork up the space-time continuum...unless you're a hyper advanced alien technology of course.
Current Status: Highly Distracted building Gatecrashing systems in Universe Sandbox!
consumerdestroyer consumerdestroyer's picture
Technically (and this is if
Technically (and this is if you decide to go with the "gates are entanglement" and/or "gates are wormholes" theory(ies), which you don't have to), the QE comm isn't going through the gate, it's going across interstellar space. So, for example, if you had a QE comm with you on a sleeper ship that took 4000 years to reach a place 4000+ light years away and then woke you up, you could talk to the people actually on the Mars of 4000 years later contemporary to you waking up (presuming x-threats didn't take them up) rather than people 8000 years in the future from when you left. Same deal with walking out of a gate: you're on the planet now, and the invisible quantum wormhole sends the instantaneous information across the stars, not back through the gate. Well, not across the stars exactly, but in any event not back through the gate.
Erulastant Erulastant's picture
Well, to the best of my
Well, to the best of my knowledge*, QE comms as described in Eclipse Phase should not work, so go with any interpretation you please. (: The two major issues with QE communications are as follows: 1. You cannot use entanglement to send meaningful information. When two particles are entangled, all that that means is that there is a relation between a particular feature of their states (For all examples I will use Spin because that has been historically easier to manipulate and test than others). Usually this is an opposite relation--If one has spin +1, the other has spin -1. For now, they each exist as a superposition of those states. The first time one of them has its spin measured, both spins become fixed to particular states (+1 or -1) and destroying the entanglement. The problem is that we can't change a state without measuring it, so if we wanted to set the particle we had to a +1, whatever process we use will first measure it and destroy the entanglement, then change ours to a +1 or leave it as a +1. But by the time we are making the change, there is no entanglement, so the other particle is still equally likely to be a +1 or a -1. (We know which it is, but the person on the other end observing it can't deduce anything from its state.) Note that this isn't a problem with QE cryptography. You simply have a large set of entangled particles, you measure them all and use that as a key for encrypting a single message. You send the message, the people with the paired set of particles realize they've been sent a message, look at their particles, and have the key for decrypting the message. 2. You can't check your mail without burning the mailbox. Remember how as soon as one side measures a particle, the entanglement is destroyed? That means that (even if you could change the state of a particle without destroying the entanglement) you could only read a message if you already knew it was there (either through real-time communication or if you set up prescheduled times for message drops). I suppose it's always possible that you could have designated sections of the reservoir to be scanned over time as an alert that there is data elsewhere. Compared to the 86 trillion qbits in a small reservoir I guess the costs of that are pretty minimal. So I guess this isn't really a problem in EP where qbits grow on trees**. Actually, if they grew on trees, they'd be quite a bit scarcer than they actually are, post-fall. *Physics student who has taken a number of Quantum courses. Not an expert by any means but with quite a bit more formal education on the subject than your average bear. **Almost worthy of being another issue on its own but that's far easier to justify with tech advancements.
You, too, were made by humans. The methods used were just cruder, imprecise. I guess that explains a lot.