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Chinese Researchers Achieve Quantum Entanglement Record

scientificamerican.com

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Re: Chinese Researchers Achieve Quantum Entanglement Record

#71

Earlier quoted context omitted.

https://en.wikipedia.org/wiki/Local_hidden_variable_theory https://en.wikipedia.org/wiki/Bell_test_experiments#Hensen_e...

These links are intended to suggest something contrary to what I've said, but they do not suggest any contradiction.

Im not an expert so from my outside viewpoint

I think by taking the guitar far away you are implying possibility of faster than light communication, which is thought to be not possible, so his links address that? Hard for me to understand so I'm just saying my thoughts out loud to get clarified, thanks

Re: Chinese Researchers Achieve Quantum Entanglement Record

#72
post #14

Earlier quoted context omitted.

Problems that are waiting to be solved by it are very large and of huge impact I know virtually nothing about quantum computing, so can you give some examples? Whenever I've asked anyone who seemed to know anything about the field, all they can come up with is weather forecasting and simulating nuclear explosions. Not exactly "general use," as you put it. In the back of my mind, I know that quantum computing is a big…

Quantum computers are extremely useful for simulating chemistry. They can do it exponentially faster than classical computers. Cheap useful quantum computers can revolutionize biology and materials science.

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Re: Chinese Researchers Achieve Quantum Entanglement Record

#73

Is entanglement an actual physical phenomenon? What exactly needs to happen in-order for a photon to "become" entangled?

Physical? As in everyday Newtonian physical? It doesn't work on quantum levels, just like Bohr's model of atom doesn't work during big bang because gravity we were successfully ignoring suddenly is on the same scale or bigger then electrostatic force. We will never be able to intuitively (physically) grasp quantum world because our intuition was trained on trees, rocks and cats.

Re: Chinese Researchers Achieve Quantum Entanglement Record

#74
post #57
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…

We would not have Amazon, Netflix, Youtube, Facebook, Google Docs, Deep Learning, name any other modern software technology or product, if we were still writing and optimizing everything by hand in assembly or C. Those "2 to 4 orders of magnitude" that are "sitting on the table" are actually being used to make it possible for developers to work at a much higher level and be much more productive. I totally agree with…

We would absolutely have all those things still writing in C, the biggest difference between C of 30 years ago and modern Java are _libraries and IDEs_, not higher level programming. Those things you listed are pretty much all Java, and Java doesn't really provide any "higher level" thinking other than forgetting about memory management.

A lot of optimizations left on the table have nothing to do with manual memory management, and have everything to do with "eh, let's just the query the database again, that'll shave a day off the schedule".

Re: Chinese Researchers Achieve Quantum Entanglement Record

#75

Earlier quoted context omitted.

These links are intended to suggest something contrary to what I've said, but they do not suggest any contradiction.

Im not an expert so from my outside viewpoint I think by taking the guitar far away you are implying possibility of faster than light communication, which is thought to be not possible, so his links address that? Hard for me to understand so I'm just saying my thoughts out loud to get clarified, thanks

The quantum state of interest is induced when plucking the conjoined "guitars". (analog for particles)

That state is induced at the moment the guitars share "locality" because entanglement requires locality for initialization of polarization.

So then, we say we are as yet unaware of the qualities of the polarization we, ourselves, induced. Very mysterious.

So spooky, yes? We do not measure, because we choose not to, so we do not yet know.

Even if we prevent ourselves from having the capacity to measure, the results hold true, but so what? And so what, if we ask others to do the same. Imagine that we ask two waiters to tape two coins together in the kitchen, flip the linked coins, peel the coins apart while preserving the outcome of the coin flip, then take one coin to your table, and one to mine. Now I know which side of the coin you are looking at, without walking over to your table. So what. Nothing about this claims transmit information superluminously.

In reality, with instrumentation, carrier signals relay an electromagnetic transmission in such a way that one cannot peek or tamper (the waiters can't change the coin flip, we cannot hear the ringing guitar), but this does not invalidate the premise of the analog. For the purposes of the analogous guitar example, we say that our couriers (electromagnetism itself) are prevented from touching or listening to the ringing guitars, or disclosing what they might sense.

With the guitars, we say the guitars move away from the place where they were entangled. We'll say that our instrumentation rang the guitars at the grand canyon. Our couriers then transported the guitars to you, at the top of the Empire State Building in New York, and me on the Golden Gate Bridge in San Francisco. I receive the guitar, and discover that the LOW E string is ringing, it can only mean that you guitar's HIGH E string in ringing in New York.

There are no local hidden variables in this example. The premise of polarity as a corollary for guitar strings is modeled in the exact same manner. Six strings on a guitar maps to the same essential parameters of each of two directions for all three axes of spin.

Re: Chinese Researchers Achieve Quantum Entanglement Record

#76
post #23
post #19

Earlier quoted context omitted.

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?

So the number of raw qubits are in the order of a million for large prime factorization or to make Shor's algorithm a reality. This is because the physical qubits are highly unstable and prone to errors. The error correction methodologies will result in a fault-tolerant logical qubit. Depending on the error correction algorithm, the ratio of logical: data/physical qubit is 1:1000 at the minimum. You need 4000 logical…

How fast do you think the number of qubits will grow over the coming years? Will it be exponential, like Moore's law?

Re: Chinese Researchers Achieve Quantum Entanglement Record

#77

Is entanglement an actual physical phenomenon? What exactly needs to happen in-order for a photon to "become" entangled?

Not sure what "actual physical phenomenon" means, but probably no. If you mean can you look at a photon and observe something about it that tells you it's entangled to some other photon, no. If you mean do we know what physical process underlies entanglement, also no. If you mean does entanglement really happen as opposed to being theoretical, yes. The link from the first paragraph of the article may help: https://www.scientificamerican.com/article/chinese-researche...

Re: Chinese Researchers Achieve Quantum Entanglement Record

#78
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?

Re: Chinese Researchers Achieve Quantum Entanglement Record

#79
post #57
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…

We would not have Amazon, Netflix, Youtube, Facebook, Google Docs, Deep Learning, name any other modern software technology or product, if we were still writing and optimizing everything by hand in assembly or C. Those "2 to 4 orders of magnitude" that are "sitting on the table" are actually being used to make it possible for developers to work at a much higher level and be much more productive. I totally agree with…

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.

Re: Chinese Researchers Achieve Quantum Entanglement Record

#80

Earlier quoted context omitted.

Im not an expert so from my outside viewpoint I think by taking the guitar far away you are implying possibility of faster than light communication, which is thought to be not possible, so his links address that? Hard for me to understand so I'm just saying my thoughts out loud to get clarified, thanks

The quantum state of interest is induced when plucking the conjoined "guitars". (analog for particles) That state is induced at the moment the guitars share "locality" because entanglement requires locality for initialization of polarization. So then, we say we are as yet unaware of the qualities of the polarization we, ourselves, induced. Very mysterious. So spooky, yes? We do not measure, because we choose not to,…

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