Quantum Internet

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I found this article very exciting. The idea of quantum entanglement being a form of instant transmission across the world, and even into deep space. Do you think in a decade this would replace satellites as our key form of world wide information distribution?

I'm hoping the cost of super-cooling the machines will be less than that of launching a satellite over the long-term. Seeing as satellites have a lifespan of only a decade or two, I think it's very likely.

We're also hitting another milestone in the number of qbits in a single machine. https://www.sciencemag.org/news/2020/09/ibm-promises-1000-qubit-quantum-computer-milestone-2023

Are we on the verge of creating a real-live ansible? https://en.wikipedia.org/wiki/Ansible
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“We learned in this work [how] to achieve this 85-90 percent [efficiency] benchmark,” says Julien Laurat, a professor and leader of the quantum networks team at the Kastler Brossel Laboratory at Sorbonne University in France. “This is the best in any physical platform.”

Previous work only achieved at most 25 percent efficiency
I don't understand. Efficiency went from 25% to 80%, of what? Do they mean that only ~20% of the energy put in is dissipated as heat? If that's not it then I honestly do not understand what they're talking about.

The idea of quantum entanglement being a form of instant transmission across the world, and even into deep space.
Unless I'm reading this wrong, it sounds like this experiment is just about increasing the information density of fiber optics by manipulating the quantum state of a light beam. That's it. They entangle the light beam at the source and they read the entanglement state at the destination, thus increasing the amount of information that can be sent, which would otherwise be constrained to either turning the light on or off.

I've never read the specifics, but I know quantum entanglement is not capable of information transmission between two entangled particles, so it's not usable as a form of instant communication.
The way I understand it (And also I'm a laymen, just have an active interest in the topic), the problem with entanglement is that it is instant. How do you work out a timing system accurate enough to measure a clock cycle when the two computers are on opposite sides of the room, let alone other sides of the world? Remember that a photon is constantly bouncing around at the speed of light. If I'm reading this correctly their accuracy improvement from 25% to (85 to 90)% has to do with correctly differentiating and storing this state change.

https://www.sciencealert.com/scientists-just-unveiled-the-first-ever-photo-of-quantum-entanglement <- The photo here shows 4 states of a photon, in all it shows an experiment to record/manipulate the alignment of an entangled photon (the other half of the pair was in a different "box" as it were). If you look at the photo of the entangled particle, there are outliers, pixels around and near the key structures. So instead of looking at a single snapshot to determine the alignment, they had to take thousands of images to build the structure that shows a general idea of how the photons were aligned. The improvement from 20% to 90% means that the structure can be determined with fewer "pictures", which means that the readings are both more accurate, and faster to compile.

This effects the number of times you have to read and resend the data in order to confirm correct delivery of an information packet, kind of like what we do with tcp vs udp...

I'm pretty sure this same problem was encountered when fiber-optics were in their infancy as well. The computers/ram weren't fast enough to manage the data so new hardware had to be invented. But now we are dealing with a system that's faster than light and requires no physical wire infrastructure to maintain. (Though the energy consumption of these experiments today is tremendous, this should be less each year as we shrink the technology down and increase its efficiency)

In the next decade this might affect the world's information on a government level rather than a personal level. At least until quantum computers are being sold to the general public (maybe half a century from now?) It's in its infancy, but it's like watching the first people experimenting and working out the shape and usage of a wheel, it might end up being nothing or it might change society as we know it...

I have edited this so many times in the last hour that I've lost track. I apologize, but this had me brimming with excitement.
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There's just no way that interpretation is right. Any kind of instantaneous communication would be a violation of causality. Imagine you send a radio transmission to an observer on a different frame of reference telling them to immediately send back the message via instantaneous transmission. Under the right conditions you would be able to receive your message back before you sent it.
And that's why Einstein hated it. It broke his understanding of physics, and helped to lead to quantum mechanics and all this crazy string theory, etc.
The main thing is that we don't need to know all the specifics of how a motor works in order to use a car. Someone else is working on how to get it working. Some day it might get wide-spread enough that we'll get to utilize/play with it.
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How much do you trust wikipedia?
"Later, however, the counterintuitive predictions of quantum mechanics were verified[5][6][7] in tests where polarization or spin of entangled particles was measured at separate locations, statistically violating Bell's inequality. In earlier tests, it couldn't be ruled out that the result at one point could have been subtly transmitted to the remote point, affecting the outcome at the second location.[7] However, so-called "loophole-free" Bell tests have been performed where the locations were sufficiently separated that communications at the speed of light would have taken longer—in one case, 10,000 times longer—than the interval between the measurements."

I will concede there is still argument on whether it can truly be called "instantaneous" but again this is down to how accurately we can measure time over a distance. It is hard to measure a latency when the bottleneck is the speed of your measuring instruments.
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I think there's multiple reasons why he didn't like QM. One, which I share, is that accepting it implies rejecting determinism. Personally, I think QM is a useful but incomplete theory. Like universal gravitation.
Hmm. You've introduced a new term to me. What is determinism? I'm googling it, but I'm not sure I'm getting the results that you mean. Would you be able to sum it up?

Google definition of determinism: "the doctrine that all events, including human action, are ultimately determined by causes external to the will. Some philosophers have taken determinism to imply that individual human beings have no free will and cannot be held morally responsible for their actions."

Do you mean fate, or religion, or is determinism more tied to physics? (I imagine Einstein wanting everything to be quantifiable by an over-reigning mathematical equation or formula). I don't think google gave me the right definition here...

Edit: This does seam to be a different turn of the topic than what I was expecting, but it is interesting. This is a part of why I find it so interesting. We may be on the verge of something incredible that changes how we understand existence... or we might be sinking billions of dollars into creating a very cold heap of cables and wires.
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"Imagine you send a radio transmission to an observer on a different frame of reference telling them to immediately send back the message via instantaneous transmission. Under the right conditions you would be able to receive your message back before you sent it."

... I don't think we're talking time travel here. Time would still be moving forward as the machines read, measure, and change the value being sent. It appears to me that a single entangled pair can only be used to send information in one direction. There is one particle in our lab that we manipulate, and the other particle is free-floating over there that they read a state from. We would need another entangled pair in which their site is manipulating that we would then read a state from on our end. Otherwise it's like two people on opposite sides of a door trying to twist the door handle in different directions. (Though we do have algorithms for sharing data over a single line, so it's not out of the question, but again it comes down to timing things correctly)

Aah! This analogy of a door handle, it is kind of like the tesseract in "Wrinkle in time" where space is essentially folded so that these two points can interact. I am so nerding out on this getting into science fantasy...
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In the purely naturalistic sense, it means that the current state of the universe is solely the result of past states of the universe and the physical laws that govern it. Since we're part of the universe, it means that our thoughts and behaviors are also entirely the result of past states of the universe, rather than human will existing at least partly outside the universe, or being unbound by physical laws.
Simply put, physical determinism means that if you know the current state of the universe (the position, momentum, etc. of all particles, the distribution of all energy, and the total space-time curvature) with infinitesimal precision and know all physical laws perfectly, then you should be able to predict the state of the universe indefinitely into the future. See: https://en.wikipedia.org/wiki/Laplace%27s_demon

Determinism should not be confused with predeterminism. Determinism merely states that the universe behaves in a specific way, but says nothing about why the particular events that do happen, happen. Predeterminism goes a step further and states that an agent external to the universe has set things in motion so that the universe looks the way it does.

Until the early 20th century, scientists had assumed that the universe being deterministic was pretty much a foregone conclusion. The advent of QM presented complex metaphysical questions that are still unanswered, such as "why is there a non-zero chance that an electron bound to a terrestrial atom can be detected in Andromeda? What's determining the behavior of the electron at any given time?"
I view QM scientists as if they are mathematicians trying to figure out Calculus. They are looking at certain aspects of things that are confusing, like what happens near a divide by zero error. They are people who are not willing to ignore the points where a line is just broken. It just so happens that there are edge cases where this information can be used to some advantage in the real world.

So I think this is like a divide by zero in a higher dimension as we perceive it from our point of view in a 4 dimensional world (position, time, width, depth). In five dimensions, this might not be a hole, but rather a point that completes a certain continuity of a greater shape.

So I get the conflict here. I would argue that determinism is right 100% of the time, except that somehow there's a 0% that somehow still manages break the equation in spots. We either have to accept the breaks in reality and move on with our lives, or we can peer through the hole.

Thank you Helios. This has been so cool. I have to go for now, but this was an excellent conversation. Thank you for your insights, and your time.
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Hey, don't mention it. I don't get to talk about this stuff anywhere near enough.
I think QM is just a start and chaos theory will have the answers. There are all these functions with effectively no way to predict their values. I think that some of them might have just the right probability distributions that match what QM has found, but with the determinism.
QM is fully deterministic, and always has been. It's just nonlocal, which confuses some people and makes them invent "interpretations"
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According to Professor Leonard Susskind & Art Fiedman in their book "Quantum Mechanics - The Theoretical Minimum":
"What we are learning is that quantum mechanical systems are not deterministic - the results of experiments can be statistically random - but if we repeat an experiment many times, average quantities can follow the expectations of classical physics, at least up to a point." ...
"Classical determinism allows us to predict the results of experiments. The quantum evolution of states allows us to compute the probabilities of the outcome of later experiments." (Their emphasis) ...
"In classical mechanics there is no real difference between states and measurements. In quantum mechanics the difference is profound."
Chaotic equations also are "indeterministic" as we understand them now, and they do tend to be cyclical, meaning the values do follow probability distributions. What makes chaotic equations so hard to work with is that even tiny rounding errors screw up the trajectories in major ways.
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Needless to say, the term 'chaotic equations' is both sufficiently ambiguous and wide-sweeping to allow for the 'indeterministic' label at least in one case.

However, the equations often used to demonstrate chaotic behavior do 3 things:
1. They demonstrate apparent randomness not actual randomness,
2. They are very sensitive to initial conditions,
3. The state at any time depends totally on the previous state.

So, the systems they describe are completely deterministic, by definition.

I agree with Cubbi on one aspect though, the problem with a lot of this is in the lay-person non-physics, non-mathematical description and interpretation.

That aside, 'local', doesn't seem to have much to do with it. For that read Susskind again.
againtry wrote:
lay-person non-physics, non-mathematical description and interpretation.
the interpretations (Copenhagen, MW, etc, including the fictional "wavefunction collapse") were generally not made by lay-persons, though it's true that they are non-physical. As for what Susskind is saying there is like if a C textbook said "arrays are pointers". Technically false, but probably helps non-experts.
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Susskind is hardly a lay person and the book I am quoting from gives the detailed mathematical derivations and support for his quoted comments. You can even visit his Stanford lecture series and see him at first hand develop the theory on a blackboard if his book doesn't suit.

I can't see the relevance or point of the c array/pointer comment especially in light of Susskind is a world-class contributor and leader in this science.

Neils Bohr et al as far as Copenhagen are concerned are not lay interpretations - they originated from differing stances by the scientific greats all coming to terms with new-found discoveries and their theories. I suspect they had no interest or care for lay thinking at the time because they had deeper philosophical concerns than the industries surrounding pseudo and popular science that often has a vested interested in making topics more obscure than less.
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It just crossed my mind that any random number generator appears to be indeterministic when it is actually deterministic. It is these types of complexities that are still unknown to the mathematical community and what leads me to believe that quantum mechanics is as indeterministic as a random number generator.

That's not to say quantum mechanics has not been a great leap in science, just that our current understanding is probably about as far as our understanding of all possible random number generators.
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