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location Baltimore, MD
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visits member for 2 years, 10 months
seen Dec 11 at 3:24

I like physics because it explains how stuff works.


Sep
24
awarded  Autobiographer
Jul
2
awarded  Curious
Jun
27
awarded  Notable Question
Apr
2
comment If quantum computing requires hundreds of digits of accuracy, how will it be possible?
So the heart of this debate seems to be whether our universe is discrete or continuous.
Apr
1
comment If quantum computing requires hundreds of digits of accuracy, how will it be possible?
There are two possibilities: 1) physics depends on the coordinates. 2) Physics doesn't depend on the coordinates. Certainly, all of the experiments of modern physics show that possibility 2) holds. But at the same time, all of the experiments of modern physics have only been shown to be true to around 10 decimal places. So it seems to me that assuming that possibility 2) is true for more than 10 decimal places is a hasty generalization.
Apr
1
comment If quantum computing requires hundreds of digits of accuracy, how will it be possible?
But what if you run your algorithm to 10 digits of accuracy on a 200-qubit machine where all of the coefficients in the state-vector are initialized to $1/2^{100}$? Then you will get zero for the state-vector in the end. This is what I was talking about in my question. This seems to me to be a big problem.
Apr
1
comment If quantum computing requires hundreds of digits of accuracy, how will it be possible?
But if QM is unitary only up to say 10 digits, how could QC work with your factoring algorithm, which requires computing the $2^n$-th root of unity in the Fourier Transform part, and the state-vector has dimension the order of $2^n$? Ten digits of accuracy is too coarse for your algorithm to work.
Mar
31
comment Water falling, why does it spin?
What is preventing the falling water from rotating? Nothing. And I think this is the conceptual answer.
Mar
30
comment If quantum computing requires hundreds of digits of accuracy, how will it be possible?
Where is the evidence that the unitary evolution is exactly unitary? The experiments that have been done to confirm QM could be interpretted as having satisfied approximate unitary evolution (to say 10 decimal places) as well as exact unitary evolution.
Mar
30
comment If quantum computing requires hundreds of digits of accuracy, how will it be possible?
But what about the fact that QM is not exactly correct and has to be corrected by QED, which is only known to be only valid to 10 or so decimals?
Mar
30
comment If quantum computing requires hundreds of digits of accuracy, how will it be possible?
Ok, now I see the point of disagreement.
Mar
30
accepted If quantum computing requires hundreds of digits of accuracy, how will it be possible?
Mar
30
comment If quantum computing requires hundreds of digits of accuracy, how will it be possible?
In your edit, you got what I was saying correctly. My point was that QC is extremely sensitive, so how will it work in the real world?
Mar
30
awarded  Critic
Mar
30
revised If quantum computing requires hundreds of digits of accuracy, how will it be possible?
added 5 characters in body
Mar
30
revised If quantum computing requires hundreds of digits of accuracy, how will it be possible?
added 23 characters in body
Mar
30
revised If quantum computing requires hundreds of digits of accuracy, how will it be possible?
added 320 characters in body
Mar
30
comment If quantum computing requires hundreds of digits of accuracy, how will it be possible?
I just updated the question.
Mar
30
revised If quantum computing requires hundreds of digits of accuracy, how will it be possible?
Explained better
Mar
30
comment If quantum computing requires hundreds of digits of accuracy, how will it be possible?
Read the link I gave. You'll see very good arguments by Levin.