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Top Questions

6 votes
1 answer
519 views

Can W gate be written only using H,T?

9 votes
1 answer
253 views

Is there a closure property for the entire Clifford hierarchy?

3 votes
1 answer
159 views

Are the pure quantum states that make up a mixed state orthogonal?

2 votes
2 answers
135 views

Why can the CNOT representation $e^{i\frac{\pi}{4}\left(I-Z\right)\otimes\left(I-X\right)}$ hardly be found in books?

1 vote
1 answer
156 views

Why do we have only 3 Pauli gates X, Y and Z

3 votes
2 answers
80 views

Is a "Bell measurement" equivalent to a projective measurement in a different basis?

3 votes
2 answers
66 views

qiskit qaoa.compute_minimum_eigenvalue

2 votes
1 answer
62 views

Qiskit: How to implement a classical function?

2 votes
1 answer
54 views

What makes dynamical decoupling a good method since the fidelity after using it can only reach 0.85 or so?

4 votes
2 answers
51 views

Why should we purify a mixed state?

2 votes
1 answer
45 views

What is the difference between $|+\rangle$ and $|-\rangle$?

2 votes
3 answers
91 views

Why do we need physical qubit if qubit can be simulated?

-2 votes
0 answers
88 views

PhD topics in quantum computing [closed]

1 vote
0 answers
84 views

Reshaping the 4x4 CNOT gate into 2x2x2x2 in a tensor network

1 vote
2 answers
49 views

How to calculate eigenvalues by phase estimation?

1 vote
2 answers
36 views

Some of the qubits are not evaluated at Qiskit

2 votes
1 answer
59 views

Barren Plateau as a consequence of 2-design?

1 vote
1 answer
42 views

What is the original paper introducing the Variational Quantum Eigensolver?

1 vote
1 answer
53 views

Performance metrics in QSVM

2 votes
0 answers
63 views

How to construct a quantum circuit that given $|\psi_0\rangle,|\psi_1\rangle$ outputs $\frac{1}{c}(|\psi_0\rangle+|\psi_1\rangle)$?

3 votes
1 answer
29 views

T-depth in Qiskit

0 votes
1 answer
47 views

Quantum algorithm to determine the existence of a solution

1 vote
1 answer
51 views

Why use superpositions to write states even when they are not entangled?

1 vote
1 answer
28 views

Jordan-Wigner map for ionic molecule H_2^+

2 votes
2 answers
35 views

Expected Minimum Clique Coverage?

2 votes
1 answer
27 views

Why does the condition $\langle \varphi _k\left( t \right) |\dot{\varphi}_l\left( t \right) \rangle =0$ called parallel transport condition?

0 votes
0 answers
43 views

What role does Landauer's principle play in quantum reverisbility?

1 vote
1 answer
25 views

Qiskit: Transpile circuit with custom equivalences

0 votes
1 answer
41 views

Expectation value of Pauli string for VQE

1 vote
2 answers
30 views

How is the ket of a quantum state calculated in this code?

3 votes
0 answers
37 views

Predator–prey theory

1 vote
0 answers
34 views

Conditional measurement using classical bit in qiskit

1 vote
1 answer
24 views

Converting data into a SHA256 hash using Qiskit quantum computer

0 votes
1 answer
30 views

How to calculate parameters of U3 gate from a certain quantum state?

2 votes
1 answer
29 views

Oracle for amplitude addition

3 votes
0 answers
28 views

How is this Variational Quantum Singular Value Decomposition paper efficient in any way?

3 votes
0 answers
27 views

Decomposing S gate in two T gate with qiskit

0 votes
0 answers
26 views

Are there hardware platforms that natively implement parametric two qubit gates?

0 votes
0 answers
19 views

How to use QubitConverter and ParityMapper to do chemistry simulation?

2 votes
0 answers
19 views

contraction related Bit flip channel

0 votes
0 answers
16 views

Is there a way to connect a IBM quantum lab code to an Unreal Engine project?

0 votes
0 answers
11 views

How to implement SU(2) rotation with qiskit?

1 vote
0 answers
11 views

Optimising state tomography for fully entangled states


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