Researchers claim quantum device performs 9,000-year calculation in microseconds Researchers in Canada have conducted a quantum computing experiment that they claim completes a calculation in just a fraction of a second that would take a conventional computer 9,000 years. Jonathan Lavoie, an experimental physicist at quantum computing company Xanadu, and colleagues reported the results from a device …
Nah
Entanglement is already proven to be *at least* 4 times faster than light. It must even be propagating backwards in time (so at least a Ryzen 99 sent from the future):
i.e. photon p1 and p2 interacts at t1, later at t2 p2 is measured and is known, so p1's state at t1 is now partially known, so p1 has changed, but p1 interacted with other photons in the past, e.g. p0 at t0, so p0's state is partially known at t0, so now all the photons it interacted with and all the matter, across the universe, very subtlely becomes more defined and known......, as the whole past and future universe changes to meet the new measurement.
So matter, light, everything, all changed by an experimental measurement in the future.
And then there's the "measurement" problem, a measurement is just an interaction, there is no difference between the two.
And the conflicting experiment problem.... the distribution assumes nobody but the particular experimentor doing the particular experiment, measures anything in the universe, either in the past or the future. Because if they were, then the photons would have partially known properties and wouldn't conform to the untouched distribution. The more experiments (past or future) the more defined.
So.... by spooky magic effect across space and time, I can tell from the future that their quantum computers never work. Because if they did, then the distribution would be narrowly defined by all the future infinite constrained quantum calculations being done in the future defining the known properties of the past!
The big big big problem. Photon uncertainty is because you are not measuring properties of the photon at all, you're measuring net properties between a detector and photon. Their probablity distribution calculation is useless, because its only true for their detector, here on this planet, here in this space at this motion at this time.
But then again, that last point, kindof removes all the magic. All that time-travel, magical quantum crap is no longer needed, if the unknowns are not from the photon, but rather the photons state with respect to any given detector, then the quantum computer is useless because it's not going through all possible states simultaneously, you just haven't measure the difference between it and the detector yet, so you (the experimenter) don't yet know the net difference, not that its unknowable.
Also for this particular experiment: Whether a digital computer can model a quantum system faster than simply building and measuring the quantum system is kind of irrelevent too, my puppy models being a puppy faster than a digital computer can model a puppy, but I don't call it puppy-supremacy, I call it puddles.
While we're here, can I point out simply why the 3 spacial dimensions cannot be independent.
Take a property, like spin, Suppose its an apparent net motion between two oscillations. One of the photon (p1) and one of the detector (d1). Now lets suppose that is in the xy plane, so it appears to be a sort of circular polarization component in the xy plane of that photon when you measure it.
A different detector, d2, has a different oscillation pattern, with respect to d2, p1 is not spinning in the xy plane, it might be spinning in a different plane, it might not even be spinning at all. i.e. the uncertainty of the spin is because the property is a net composite of detector and detected.
Hence the 3 spacial axis are partially a function of the observer, they are not universal and certainly not independent.
The above, is so fooking obvious when I put it like that, so don't go modelling space in 3 independent dimensions as if those dimensions extend across the universe.
And don't go thinking that spiral polarization is entirely a function of the photon, when it clearly isn't.
And also, motion is a waddle in 3 axis over an oscillating field. If you want to capture a photon, cancel out one of of those components and it will become a stationary spin. Since this happens in matter, (photons get captured, capturing electrons gain motions as a result), you can tell that the effect is a net interaction between matter and the photon. You see how the properties of the photo could *not* be independent of the detector. If you're able to detect it, and able to capture the photon, then there is a net interaction.
So! Entanglement is not faster than light in that there is no "travelling" happening between the two particles. Two entangled particles have a shared quantum state, which is broken as soon as one particle interacts with any other particle or field. Until then both particles exist in both/all states simultaneously. Once interacted, the spin of one particle immediately implies the opposite spin in the other - the quantum state is determined instantaneously. The act of measuring the spin also counts as an interaction and would thus break the entanglement. It cannot thus be used for any meaningful superluminal communication. There is no time travel, it's just how quantum physics works, but casualty is always preserved.
As for spin, the atomic particles do not actually spin. At the subatomic level, charged particles (electrons and protons) act like tiny little magnets. Since magnetism appears when a charged particle is moving, it baffled scientists that a charged particle not moving much could have such a strong magnetic field. Back in the old days, they assumed that the particles were solid and spinning, and it was this spin creating the magnetic field. However with the advent of quantum physics, it became clear that the particles were not actually spinning as they're not solid but instead point-like particles (the quarks are, protons are not as they're made up by quarks). The name spin stuck, but really in simple terms, it would be called "intrinsic magnetism". This "spin" exists only in certain states, so unlike a magnet it's, as you'd expect in Quantum physics, "quantized".
This is a good observation!
Photons: I'm not 100% sure, but my understanding is that the spin of a photon particle correlates to the polarization of the wave. Light waves are electromagnetic fields. However the "spin" in charged particles is ±½ and in photons it's ±1. If I understood, correctly: ½ means it interacts via charge, 1 means it does not. How spin works scientifically and mathematically, is beyond me.
Neutrinos: Theoretically neutrinos do have a magnetic moment, the strength which is really really tiny. So tiny it has never been experimentally verified.
As far as I can make out from the brief summary they performed a particular quantum experiment chosen to be very difficult to emulate numerically and predicted it would take a supercomputer 9,000 years to emulate and present the result as a triumph of quantum computing. Could they use this technique to show that a quantum computer would be better at weather forecasting than a conventional computer or than the atmosphere itself.
However, there is a significant point. The computational complexity folks have a strong record of being able to recast one type of problem as another. SAT problems etc. That’s where the whole NP Complete thing comes from: any problem in that complexity class can be numerically recast as anything else in that class, with only polynomial-time additional complexity.
As I understand, nobody has *yet* been able to connect Gaussian boson sampling to more interesting algorithms. That’s a separate problem. Probably that will be solved by high-power mathematicians in years rather than decades. Once that has been done, there will be a polynomial-time “trick” to convert your more interesting but exponentially hard problem to one stated as GBS, solve that on this quantum computer, and then convert the result back.
It’s a bit like Fourier transforms O(N^2) seem only useful for some quite particular physics problems, but then once FFTs O(NlogN) were invented, *so many* unrelated bits of computation started using them.
So that’s really the point of all this quantum stuff.
I will get excited when quantum computer shall calculate something that is useful and non-trivial, regardless of if it's faster or slower than concurrent digital computers.
I understand that this news may be a stepping stone towards something greater, but so far results that quantum computing have demonstrated have been either computationally trivial or of no practical use.
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