Strilanc

13 ms·

61.
by Strilanc 1y ago
Can you provide the source for that quote? 5 billion years seems way too soon. The Hubble constant is currently approximately one doubling per 14 billion years [1]. So 5 billion years isn't enough to double the recession speeds. AFAIK
62.
by Strilanc 1y ago
Glad you liked it. Note the 2013 paper wasn't making the same point. They weren't pointing out that Shor's algorithm succeeds quickly regardless of how well the quantum computer works when factoring small numbers. They proved
63.
by Strilanc 1y ago
Related short story: the whispering earring http://web.archive.org/web/20121008025245/http://squid314.li...
64.
by Strilanc 1y ago
They also allow the solvers a move that measures the superposition, and if the state collapses to the solved state then that's a finish (otherwise the puzzle resets to the initial scrambled state). So a viable quantum strategy is to ju
65.
by Strilanc 2y ago
Could you provide the code you use to trivially catch signed overflows? My impression is the opposite: unsigned is trivial (just test `a+b < b`) while signed is annoying (especially because evaluating a potentially-overflowing expression
66.
by Strilanc 2y ago
The delayed choice experiment doesn't contain a bell inequality, so spacelike seperation doesn't really mean much here. You can reproduce the results with local classical models.
67.
by Strilanc 2y ago
I don't think it has anything to do with what we know "now". It's just paying attention to the fact that the signal photon hitting the screen causes a collapse that affects the state of the idler photon. Which then expla
68.
by Strilanc 2y ago
Using the largest number factored as a benchmark for progress in quantum computing is like evaluating floor(f(0)) = 0 and floor(f(1)) = 0 and concluding f(x) = 0. You can't distinguish f(x) = 0 from f(x) = x/2 from f(x) = e^x&#x2F
69.
by Strilanc 2y ago
I was wondering why the article didn't show the actual ansatz anywhere. So I looked it up on Wikipedia [1] and then I understood why. It's a product over pairs around a sum over permutations around an exponential of a sum over pai
70.
by Strilanc 2y ago
Yeah, network latency and client side prediction and accuracy will also play huge roles. The actual distributions will be very complex, but in general reacting faster is going to be better.
71.
by Strilanc 2y ago
It doesn't need to be perceptible to cause a difference in a game. Suppose two players notice each other at the same time (e.g. as would naturally happen when walking around a corner in a shooter), first to shoot wins, and their total
72.
by Strilanc 2y ago
Yes it exceeded break even, but no you can't just copy paste hardware yet. For example, some kind of chip-to-chip coupling is needed since chips can't be arbitrarily large.
73.
by Strilanc 2y ago
In principle quantum communication has no side channels because side channels act like measurements, and measurements make it not a functioning quantum channel in the first place. So you need to have already solved side channel issues for b
74.
by Strilanc 2y ago
Distillation will still work if the inputs are slightly entangled with each other or with other qubits. I recommend just simulating the specific case you're worried about. It's only a 15 qubit circuit; not at all expensive to chec
75.
by Strilanc 2y ago
There are two major issues with the paper you linked. First, it says if you can't do accurate rotations then you can't factor. But the premise is false. Quantum error correction allows you to do arbitrarily accurate rotations.
76.
by Strilanc 2y ago
I don't think anyone has managed to write down a super deterministic model that can violate bell inequalities and contain computers. The computer bit is key here because it's what let's me create ludicrously difficult to solv
77.
by Strilanc 2y ago
The key difference is that the problem being solved is a math problem. It can be written down on paper. A ball falling on the ground can be converted into a math problem. To get the conversion exactly right you will need to write down the e
78.
by Strilanc 2y ago
I don't see people who believe hidden variable models, like pilot wave, claiming quantum computers won't work. So I don't think quantum computers disprove hidden variable models. I do agree quantum computers disprove local
79.
by Strilanc 2y ago
The main issue with this line of argument is that you don't see people who like other interpretations claiming quantum computers won't work. Saying quantum computers imply many worlds is the classic mistake of wanting to show A=&g
80.
by Strilanc 2y ago
The most recent result on reducing the number of logical qubits is [1]. They show how to use residue arithmetic to factor n bit numbers using n/2 + o(n) logical qubits (they give the example of 1730 qubits to factor a 2048 bit number).
81.
by Strilanc 2y ago
I'm not trying to be evasive. I'm directly saying quantum computers won't factor interesting numbers for years. That's more typically described as biting the bullet. There are several experiments that claim to factor 15
82.
by Strilanc 2y ago
Like I said above, the size of number that can be factored will sit still for years while error correction spins up. It'll be a good metric for progress later; it's a terrible metric for progress now. Too coarse.
83.
by Strilanc 2y ago
If qubit count increased by 2x per year, largest-number-factored would show no progress for ~8 years. Then the largest number factored would double in size each year, with RSA2048 broken after a total of ~15 years. The initial lull is becau
84.
by Strilanc 2y ago
The experiment is literally all about scaling. It tests scaling from distance 3 to 5 to 7. It shows the logical qubit lifetime doubles each time the distance is increased. The sentence you quoted is describing an expectation that this doubl
85.
by Strilanc 2y ago
The full error correction system involves qubits. This paper is mainly about the decoder, which is responsible for taking the symptom data produced by the quantum circuit and determining the most likely errors that caused those symptoms. In
86.
by Strilanc 2y ago
At the time they announced the image they described some of the extrapolation they had to do to fill in the image [1]. IIRC I saw a talk that described some of the different methods, but I can't find it now. I recall it was about turni
87.
by Strilanc 2y ago
(1) distributed computation. If you can network two quantum computers, you essentially have one quantum computer with twice the storage. Quantum networks avoid the need to build one enormous quantum computer. (2) easier experiments. Current
88.
by Strilanc 2y ago
> What are we going to do, run direct fiber from every computer to every other computer directly? No, you don't have to do that. A quantum network would be a web of point-to-point quantum links, with paths formed by routers choos
89.
by Strilanc 2y ago
How hard do you expect it would be to improve the heralded infidelity from 45% to 10%? In figure 3 of the paper [1] the heralded infidelity of entanglement is reported to be around 45%. That's not good enough for computation, but it&#
90.
by Strilanc 2y ago
Overall this article looks pretty good. There was one major numerical error I noticed, but then the article corrected itself at the end. This was the error: > With an error rate of 1% the surface error correction code requires ~ 500 phy

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