All Questions
Tagged with swap-test linear-algebra
6 questions
2
votes
0
answers
84
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Given three quantum states, how to compute the triple product of amplitudes $\sum_i u_i v_i w_i$?
Assume I have three quantum states $|u\rangle$, $|v\rangle$ and $|w\rangle$ which can be obtained with three quantum circuits $U$, $V$ and $W$.
We know that we can easily estimate the inner product $\...
- 181
4
votes
1
answer
316
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What is the "additive error" of Swap Test?
I'm learning the Swap Test, a quantum circuit to calculate the inner product of two quantum states $|\langle \phi|\psi\rangle|^2 $:
For the error analysis of this quantum circuit, according to Swap ...
- 365
5
votes
1
answer
543
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Fidelity (overlap) test over reduced density matrices on quantum circuit
The inner product between two quantum states
$\rho(x_1) = U(x_1)|0\rangle\langle 0| U^\dagger(x_1)$ and
$\rho(x_2) = U(x_2)|0\rangle\langle 0| U^\dagger(x_2)$ can be calculated analytically with $Tr[\...
- 817
3
votes
1
answer
61
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SWAPing Schmidt vectors
Can anything be said about the inner product of a bipartite entangled state with itself but with the Schmidt vectors swapped? That is, if the Schmidt decomposition of a state is given by
$$\vert \psi \...
- 609
0
votes
0
answers
44
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How to obtain the product of the amplitudes of arbitrary basis vectors in a superposition state without measuring?
Suppose there is a superposition state $|{{\Phi }^{+}}\rangle =\sum\limits_{i=0}^{15}{{{\alpha }_{i}}|i\rangle }$, I want to get ${{\alpha }_{i}}\times {{a}_{j}},i\ne j,i,j\in [0,15]$ without ...
- 546
3
votes
1
answer
757
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How to calculate inner product of quantum states with other method than swap test? [duplicate]
In connection to this question, I am wondering how to calculate value $\langle \psi|\phi \rangle$ for arbitrary quantum states $|\psi\rangle$ and $|\phi\rangle$.
A swap test is able to return only $|\...
- 14.9k