a reply to:
Reverbs
The "error correction code" and qubits as approached by "conventional" thinking seems off to me. I will try and explain.
Error-correction in comp. sci. is a typical problem. From what I can recall a method of detection and another for correction are required. Typically,
this involves the notion of “parity” which you can see when you divide a number by 2: either you have a remainder of 0, or, a remainder of 1.
Usually used in communication, the binary digits in the set length of the word are added up (sum doesn't matter), if it sums to odd, the parity bit is
set to 1, otherwise, 0; if the received parity bit does not match the message it is sent again. In the article they give the example of using 3-qubits
to track a qubit flip also using parity.
This method uses a crap load of your difficult to generate qubits (and what if your guardian qubits get flipped??). And thing is, most people forget,
that this is a 3D object, not a binary digit. Which means it is rotated! The point on a sphere, like a city on globe, moves when rotated; but you can
also flip it upside down! That is what Hamilton came to the conclusion when he defaced the bridge with his equation: I = j = k. Means, you need to
take 2 steps to get back to the original orientation (what they are talking about is limiting the quantum state to up-down so they just want to get
back to the previous state). Why?!! Let chaos rule is say!
The 3-qubits are encoding 3D space by keeping track of all 3 possibilities at once, which, to me, is a waste of space! Why not encode the changes in a
non-quantum manner (it would just be a scalar matrix) since you know how the quantum vector can change (i=j=k)? Save you a bunch of steps of trying to
keep homeostasis (??? whateverz it is called in QM), then just keep track of how many times you flipped. Then when you reach a limit (unknown), then
you put the effort back to creating the original QM entangled qubit state?
To me, seems a bit over thought out. Surely universe doesn’t need 3 times the amount of matter and energy to keep everything from happening (or
maybe that is what “dark energy” actually is! The non-dimensional error buckets keeping the universal constants recorded while entangled matter
flies all over the place until it encounters more matter and needs to “know” what to do [i.e., the QM state is ‘read’ at that point and the
wave does the collapse], then the visible becomes manifest. Consciousness is not a “being” but a “QM state of being” which is maybe why
everything is connected! Heavy neutron star thoughts on a Monday morning!)
I really hate "reading about math" and would rather see the real deal. But that has meant that to read quantum mechanics I have had to learn the
language that it is spoken in: Bra-ket. That is what they show in the article:
| 0 > α
Which is shorthand for performing matrix math with real numbers. The above is zeroing out a matrix, α, by assigning it the value "0". That is the
easy part. Realizing that you are cross multiplying matrices and going from single row and single column to a 2D matrix, is the hard part.
I found this paper by one Todd Brunn at USC that shows the math (pdf):
Quantum Error
Correction and Quantum Error Correction Codes.
Not saying I can sling this around at a glance but thinking about what is being said begins to make sense to me. And why I think it is "over
engineered" a qubit (groan! I could not help myself!
)
I hope this helps with the "technical" side of what is being discussed and sorry if I went too technical too. I am learning all this as I read
articles like one in Quanta magazine. The nice thing about explaining it is that it helps me understand things better. You can learn by doing, or, you
can learn by teaching. Rare is the individual who gets to get plugged into the Matrix and have knowledge downloaded to their brains!
Class dismissed!!