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Quantum Computing: Wrong X gate in circuit for AH2 and |q1> (page 309)

zoufala

zoufala

Quantum Computing: Wrong X gate in circuit for AH2 and |q1> (page 309)

@nihal.mehta

I’m just starting with quantum computing, therefore I’m not completely sure. But for me the bottom-left X gate in the circuit diagram looks wrong, I think it should be an H gate?

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First Post!

nihal.mehta

nihal.mehta

Author of Quantum Computing

Hello,
Yes you are correct. The bottom gate in the left AH2 block should be an H gate, not X as shown. The figure is incorrect.
The matrix equation at the bottom of the page is also incorrect. Specifically, the matrix on the right of the 5 matrix multiplication should be replaced with the matrix on the left. The result though is correct.
Thanks for pointing this out.
Best,
Nihal

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