5 ms·

A brief introduction to quantum computing

94 points by friedrich12 8y ago

bra-ket 8y ago
for a great primer on quantum computing see https://docs.microsoft.com/en-us/quantum/quantum-concepts-4-qubit?view=qsharp-preview https://docs.microsoft.com/en-us/quantum/quantum-concepts-4-...
virgil_disgr4ce 8y ago
I don't want to sound like a jerk or anything but you'd think that if a high schooler could write an entire paper like this about quantum computing of all things they'd be able to spell a few more things correctly, get basic punctuation right, grammar, etc.?
- awat 8y ago
  Phrased another way this is a great example of why the breakdown of a cumulative score (verbal vs quant, etc) is important on standardized tests.
- DoreenMichele 8y ago
  Maybe you would, but I wouldn't. First, those are unrelated skill sets. Second, lots of people excel in one area and suck in another. That's completely normal.
- samhain 8y ago
  >Quantum computing is a chance a solving problems that are considered unsolvable classical computers. Quantum computing is a relatively new and complicated field in this paper I provide a brief overview of quantum computing systems. I agree, the abstract doesn't even make sense and has run-ons. It looks like they didn't even bother to run it through spell check. I must admit their formatting is very nice. It looks like they might have used LaTex.
- code_duck 8y ago
  Since they don't proofread words effectively and missed simple mistakes like 'silt' for 'slit', it makes me doubt that the formulas have been proofread thoroughly, either.
- threatofrain 8y ago
  Those things become far less important as your thinking becomes more attractive for others to read. Also plenty of people don't do their own editing.
- coyoterabbit 8y ago
  It was a jarring read seeing those basic mistakes. Even just a once-over before publishing to web would have likely caught those typos and increased the credibility of the paper. Perhaps the author was tight for timeline or couldn't source a peer reviewer.
  - friedrich12 8y ago
    It was due on the day I finished it. Sorry for the grammar mistakes.
mathgenius 8y ago
Quantum computing is all about the tensor product. This is, roughly, how "and" works in the quantum world. Learning about tensor products by calculating with matrices is dizzyingly complicated [1]. But there's another way, using string diagrams [2]. [1] https://en.wikipedia.org/wiki/Kronecker_product https://en.wikipedia.org/wiki/Kronecker_product [2] https://arxiv.org/abs/0908.1787 https://arxiv.org/abs/0908.1787
- asafira 8y ago
  Quantum computing being all about the tensor product is like saying state-of-the-art image recognition is all about matrix multiplication. There is a hell of a lot more to it.
- amluto 8y ago
  I wouldn’t say the tensor product is how “and” works. “and” usually refers to the Boolean and operator. The tensor product is how combining two systems works. In classical computing, if you have: int a; int b; The set of possible states is the Cartesian product of the states of a with the states of b. In quantum computing, it’s the tensor product instead. It’s not terribly complicated to work with the matrices — they’re just huge. Fortunately, it’s not usually necessary to write out the matrices at all. I read the string diagram paper. It’s supposed to be comprehensible to kids, but I couldn’t make heads or tails of it. (I did my Ph.D. on quantum computing.)
gregfjohnson 8y ago
This is really impressive for a high school student.
ianai 8y ago
i once read about a theory of matter where under the right circumstances a larger system of quantum particles may act in a way consistent to a system composed of fewer particles. The larger solution approaches an exchange of, say, one electron or photon when really it’s an exchange of many particles. Does anyone know the name for that area of study? To answer my own question: quasiparticles I can’t help but think that may be a more tractable QC construction.
- asafira 8y ago
  Unfortunately, things are quite a bit more complicated than this. The current issues in quantum computing aren't so much that it becomes difficult to describe a many-qubit system, but that those qubits individually (and pair-wise) aren't well controlled, and we just aren't good at coming up with many algorithms given these constraints.
  - ianai 8y ago
    Yes, and I’m wondering whether the current qubits are too fragile. Like whether there’s a way to construct a qubit out of a more naturally rebalancing system - somewhat analogous to an acid base buffer.
thr0000waay 8y ago
non-commutative geometry will ruin his life.

94 points by friedrich12 8y ago

for a great primer on quantum computing see https://docs.microsoft.com/en-us/quantum/quantum-concepts-4-qubit?view=qsharp-preview https://docs.microsoft.com/en-us/quantum/quantum-concepts-4-...

virgil_disgr4ce 8y ago

I don't want to sound like a jerk or anything but you'd think that if a high schooler could write an entire paper like this about quantum computing of all things they'd be able to spell a few more things correctly, get basic punctuation right, grammar, etc.?

awat 8y ago
Phrased another way this is a great example of why the breakdown of a cumulative score (verbal vs quant, etc) is important on standardized tests.
DoreenMichele 8y ago
Maybe you would, but I wouldn't. First, those are unrelated skill sets. Second, lots of people excel in one area and suck in another. That's completely normal.
samhain 8y ago
>Quantum computing is a chance a solving problems that are considered unsolvable classical computers. Quantum computing is a relatively new and complicated field in this paper I provide a brief overview of quantum computing systems. I agree, the abstract doesn't even make sense and has run-ons. It looks like they didn't even bother to run it through spell check. I must admit their formatting is very nice. It looks like they might have used LaTex.
code_duck 8y ago
Since they don't proofread words effectively and missed simple mistakes like 'silt' for 'slit', it makes me doubt that the formulas have been proofread thoroughly, either.
threatofrain 8y ago
Those things become far less important as your thinking becomes more attractive for others to read. Also plenty of people don't do their own editing.
coyoterabbit 8y ago
It was a jarring read seeing those basic mistakes. Even just a once-over before publishing to web would have likely caught those typos and increased the credibility of the paper. Perhaps the author was tight for timeline or couldn't source a peer reviewer.
- friedrich12 8y ago
  It was due on the day I finished it. Sorry for the grammar mistakes.

mathgenius 8y ago

Quantum computing is all about the tensor product. This is, roughly, how "and" works in the quantum world. Learning about tensor products by calculating with matrices is dizzyingly complicated [1]. But there's another way, using string diagrams [2]. [1] https://en.wikipedia.org/wiki/Kronecker_product https://en.wikipedia.org/wiki/Kronecker_product [2] https://arxiv.org/abs/0908.1787 https://arxiv.org/abs/0908.1787

asafira 8y ago
Quantum computing being all about the tensor product is like saying state-of-the-art image recognition is all about matrix multiplication. There is a hell of a lot more to it.
amluto 8y ago
I wouldn’t say the tensor product is how “and” works. “and” usually refers to the Boolean and operator. The tensor product is how combining two systems works. In classical computing, if you have: int a; int b; The set of possible states is the Cartesian product of the states of a with the states of b. In quantum computing, it’s the tensor product instead. It’s not terribly complicated to work with the matrices — they’re just huge. Fortunately, it’s not usually necessary to write out the matrices at all. I read the string diagram paper. It’s supposed to be comprehensible to kids, but I couldn’t make heads or tails of it. (I did my Ph.D. on quantum computing.)

gregfjohnson 8y ago

This is really impressive for a high school student.

ianai 8y ago

i once read about a theory of matter where under the right circumstances a larger system of quantum particles may act in a way consistent to a system composed of fewer particles. The larger solution approaches an exchange of, say, one electron or photon when really it’s an exchange of many particles. Does anyone know the name for that area of study? To answer my own question: quasiparticles I can’t help but think that may be a more tractable QC construction.

asafira 8y ago
Unfortunately, things are quite a bit more complicated than this. The current issues in quantum computing aren't so much that it becomes difficult to describe a many-qubit system, but that those qubits individually (and pair-wise) aren't well controlled, and we just aren't good at coming up with many algorithms given these constraints.
- ianai 8y ago
  Yes, and I’m wondering whether the current qubits are too fragile. Like whether there’s a way to construct a qubit out of a more naturally rebalancing system - somewhat analogous to an acid base buffer.

thr0000waay 8y ago

non-commutative geometry will ruin his life.