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Chinese Researchers Achieve Quantum Entanglement Record

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Re: Chinese Researchers Achieve Quantum Entanglement Record

#101
post #13

Crash course in entanglement: The state of each qbit is represented by a state vector of two complex numbers [a, b] where |a|^2 + |b|^2 = 1. There are two special qbit values called the classical basis : [1, 0] which is the classical bit 0, and [0, 1] which is the classical bit 1. If a qbit is not in one of the two classical states, we say it is in superposition . When a qbit is in superposition, we can measure it[0]…

Since speed warps spacetime, does the relative speed of the qubits change this? Can they go out of sync if one is moved much faster than the other for a prolonged period of time? If not, could this property be used for a universal clock?

"Much faster than the other" relative to what?

There is no absolute motion or speed. There is only relative motion or speed.

Re: Chinese Researchers Achieve Quantum Entanglement Record

#103
post #19
post #4

I visited USTC several years ago, (2014) and in this time they have basically doubled the number of qubits they can entangle, so this is a great step forward. At around ~100 qubits quantum computing becomes very useful, so maybe we won't have to wait too long.

What's the size needed for cracking large-primes based encryption? If not at 100 qubits, what are some useful calculations that we can do at that size?

2048 would break current crypto, >20 would help solving most unsolvable NP hard problems.

Re: Chinese Researchers Achieve Quantum Entanglement Record

#104
post #15

Earlier quoted context omitted.

We all have these things in our pockets that are massive supercomputers by the standards of my college days. And we all use them just to rant at each other about political things that we in reality are totally misinformed about ... and otherwise just waste our lives. I am not sure why quantum computing is supposed to change this. Even software that is supposed to be useful is so terribly slow. Computers are between 2…

The introduction of automobiles permitted the development of F1 racecar drivers, but just ended up with most people dragging themselves around to get food and money. The introduction of the printing press permitted the publication of pamphlets and books that overturned world governments and dethroned kings... but most people used it to trade porn and recipe books. Technology doesn't make people better. It lets people…

"The introduction of the printing press permitted the publication of pamphlets and books that overturned world governments and dethroned kings... but most people used it to trade porn and recipe books."

As Timothy Snyder notes when discussing the internet, the introduction of the printing press divided Western Christianity thereby causing a century and a half of religious wars in which a third of the population was killed. And later it gave us the Enlightenment and educated society.

Re: Chinese Researchers Achieve Quantum Entanglement Record

#105
post #79

Earlier quoted context omitted.

I disagree. The slowness of these languages is mostly uncorrelated with increases in productivity. People only think there’s cause-and-effect here because they haven’t seen counterexamples, because the trend in language design for 25 years has been to make slow languages.

They haven't seen counterexamples because there are virtually none. If what you said was correct wouldn't there be many examples of big bodies of code written in a language like C? (And you can't say "linux kernel" - low-level code needs to be written in a low-level language, in order to communicate with the lower levels like hardware and controllers and such. There is a practical reason to write that in C.) > becaus…

> you can't say "linux

Can I say "pretty much all of Linux userspace"? Or Java VM? Or Gnome?

Re: Chinese Researchers Achieve Quantum Entanglement Record

#106

Earlier quoted context omitted.

Thanks, this helps a lot, but just to clarify: Originally "We 'shine' a bunch of photons at an object, and see if they come back. Except there could be dragged decoy spamming photons back at us, and we don't know if there is. Or it could be sending out so much light, our photons coming back are lost in the mix." With quantum: "We can verify that any photons that get reflected are the ones that we sent out and check o…

Right. Oversimplifying a lot, it's putting a name tag on the photons. Then you can sort out the tagged ones from all the others, drastically reducing the practical noise floor.

Interesting. Is generating entangled protons so trivial that this is feasible now?

It seems like it would take millions (more?) of entangled protons per second to achieve this. And then these can be sensed, verified, and measured at such speed that it could be used as radar?

It sounds far fetched, but I would love to know if this process is already that quick and easy.

Re: Chinese Researchers Achieve Quantum Entanglement Record

#107
post #96

Earlier quoted context omitted.

It's just an expression of the conservation of energy. Much in the same way the double slit experiment conflates a particle transporting itself through two windows at once, so too, do these experiments conflate the polarizers as causing the effect. Ask yourself: if you construct a gun, with two diametrically opposed barrels, with exactly opposed rifling twists, and you aim the gun at two opposing (but identical) abra…

No, no, no. There is almost half a century of experimental evidence against you. The experimental results of Bell test experiments are incompatible with the assumption that the states of both particles are fixed when the pair is generated and are only classically correlated because of the way their states are fixed. All your analogy attempts are flawed and bound to fail exactly because entangled pairs of quantum part…

Except you can't tell me what the spin is without polarizers. This is like telling me I have to measure the orientation of a fidget spinner with a fitness club's treadmill set to the brisk pace of an uphill jog.

None of the experiments don't use polarizing lenses to make a determination of results on both sides. This is where the experiments are fundamentally flawed and propose weak evidence.

To simply read about the fundamentals of light polarization is to understand that quantum wave function collapse is much ado about nothing, and it becomes obvious that all this contention is total bullshit, and none of it is magic.

https://en.wikipedia.org/wiki/Polarizer

https://en.wikipedia.org/wiki/Polarizing_filter_(photography...

https://en.wikipedia.org/wiki/Photon_polarization

Re: Chinese Researchers Achieve Quantum Entanglement Record

#108
post #96

Earlier quoted context omitted.

It's just an expression of the conservation of energy. Much in the same way the double slit experiment conflates a particle transporting itself through two windows at once, so too, do these experiments conflate the polarizers as causing the effect. Ask yourself: if you construct a gun, with two diametrically opposed barrels, with exactly opposed rifling twists, and you aim the gun at two opposing (but identical) abra…

No, no, no. There is almost half a century of experimental evidence against you. The experimental results of Bell test experiments are incompatible with the assumption that the states of both particles are fixed when the pair is generated and are only classically correlated because of the way their states are fixed. All your analogy attempts are flawed and bound to fail exactly because entangled pairs of quantum part…

Except you can't tell me what the spin is without polarizers. This is like telling me I have to measure the orientation of a fidget spinner with a fitness club's treadmill set to the brisk pace of an uphill jog.

None of the experiments don't use polarizing lenses to make a determination of results on both sides. This is where the experiments are fundamentally flawed and propose weak evidence.

To simply read about the fundamentals of light polarization is to understand that quantum wave function collapse is much ado about nothing, and it becomes obvious that all this contention is total bullshit, and none of it is magic.

https://en.wikipedia.org/wiki/Polarizer

https://en.wikipedia.org/wiki/Polarizing_filter_(photography...

https://en.wikipedia.org/wiki/Photon_polarization

Re: Chinese Researchers Achieve Quantum Entanglement Record

#109
post #96

Earlier quoted context omitted.

No, no, no. There is almost half a century of experimental evidence against you. The experimental results of Bell test experiments are incompatible with the assumption that the states of both particles are fixed when the pair is generated and are only classically correlated because of the way their states are fixed. All your analogy attempts are flawed and bound to fail exactly because entangled pairs of quantum part…

Except you can't tell me what the spin is without polarizers. This is like telling me I have to measure the orientation of a fidget spinner with a fitness club's treadmill set to the brisk pace of an uphill jog. None of the experiments don't use polarizing lenses to make a determination of results on both sides. This is where the experiments are fundamentally flawed and propose weak evidence. To simply read about the…

If you read through the list of Bell test experiments [1], you will discover that not all of them are done with photons, for example »Violation of Bell’s inequality in Josephson phase qubits« [2].

[1] https://en.wikipedia.org/wiki/Bell_test_experiments#Notable_...

[2] https://web.physics.ucsb.edu/~martinisgroup/papers/Ansmann20...

Re: Chinese Researchers Achieve Quantum Entanglement Record

#110

Earlier quoted context omitted.

Except you can't tell me what the spin is without polarizers. This is like telling me I have to measure the orientation of a fidget spinner with a fitness club's treadmill set to the brisk pace of an uphill jog. None of the experiments don't use polarizing lenses to make a determination of results on both sides. This is where the experiments are fundamentally flawed and propose weak evidence. To simply read about the…

If you read through the list of Bell test experiments [1], you will discover that not all of them are done with photons, for example »Violation of Bell’s inequality in Josephson phase qubits« [2]. [1] https://en.wikipedia.org/wiki/Bell_test_experiments#Notable_... [2] https://web.physics.ucsb.edu/~martinisgroup/papers/Ansmann20...

https://en.wikipedia.org/wiki/Inconsistent_comparison

Josephson phase qubits aren't even utilizing the same fundamental concepts to examine the qualities of the mediums that quantum uncertainty affects.

https://en.wikipedia.org/wiki/Phase_qubit

https://en.wikipedia.org/wiki/Josephson_effect

https://en.wikipedia.org/wiki/Josephson_voltage_standard

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