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Top Questions

0 votes
1 answer
18 views

Confusion regarding the definition of state of a qubit

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0 answers
13 views

how to write electron spins using bra-ket notation?

0 votes
0 answers
16 views

Does the Hadamard gate synchonize the complex coefficients of the various states?

2 votes
3 answers
554 views

Why do we need Entanglement?

0 votes
2 answers
17 views

What is the use of Period Finding in Shor's algorithm? What we measure with it?

0 votes
1 answer
17 views

AttributeError: module 'cirq_google' has no attribute 'Foxtail'

0 votes
0 answers
15 views

Clarification regarding application of distributive property in "quantum teleportation" example

1 vote
1 answer
33 views

Question regarding a step in the computation of $QFT_{16} \frac{1}{2} ( \mid 1 \rangle + \mid 5 \rangle + \mid 9 \rangle + \mid 13 \rangle )$

0 votes
0 answers
16 views

How is the Pauli X, Y, Z implemented in order to "flip" the complex phase of the state probability?

1 vote
1 answer
25 views

Gottesman-Knill theorem -- last measurement step

2 votes
1 answer
79 views

Are $n$-qubit Pauli channels $\mathcal E(\rho)=\sum_j p_j P_j \rho P_j$ invertible?

1 vote
1 answer
87 views

How can I find the documented T1 time of a retired IBM system?

0 votes
1 answer
19 views

How to resolve ValueError: The circuit contains non-deterministic observables

0 votes
0 answers
12 views

What would be the simplest physical implementation of a CNOT operation between spin and energy DoF's?

0 votes
1 answer
16 views

Quantum algorithms and binomial distributions and probabilities

1 vote
1 answer
42 views

Are there qiskit or stim examples of how to decode a subsystem code

1 vote
1 answer
94 views

Can we rearrange terms in the tensor product?

1 vote
3 answers
37 views

How to join different quantum circuits into one big circuit on specific qubits in qiskit?

0 votes
0 answers
12 views

How to create a multicontrol mcx gate or operation in cirq

1 vote
2 answers
91 views

Where can I find tutorials on quantum variational algorithms?

1 vote
0 answers
12 views

Average-case error and worst-case error in entangment-assisted classical communication

2 votes
1 answer
94 views

Can you distinguish between $|0\rangle, |1\rangle$, and $\frac{1}{\sqrt 2} (|0\rangle + |1\rangle)$?

0 votes
1 answer
36 views

The operator of the composite system given the operator of the single system

0 votes
1 answer
38 views

Differences in Simulating Syndrome Measurement Circuits with Prepared States : $|0_L \rangle$ vs $|0\rangle^{\otimes n}$

-2 votes
1 answer
49 views

Unitary matrix knowing input and ouput states

1 vote
1 answer
63 views

How to write a Stabilizer state in terms of sum of Pauli strings?

1 vote
1 answer
96 views

Quantinuum corporation says they have a Bell test for quantum randomness. Why does the simulator pass the test?

2 votes
1 answer
109 views

How to convert a simple matrix into circuit? [duplicate]

2 votes
1 answer
121 views

How does VQE work?

1 vote
0 answers
18 views

Need help to understand topological color codes

0 votes
0 answers
14 views
+50

Which applications of quantum singular value transformation use block-encodings in apriori unknown bases?

1 vote
1 answer
48 views

How to convert a basic matrix into a quantum circuit?

2 votes
2 answers
111 views

In the qiskit QFT demonstration, how to implement CPHASE between Q0 and Q1?

0 votes
0 answers
39 views

python code to approximate an arbitrary 2*2 unitary matrix with gates H,T and Z

3 votes
2 answers
198 views

Name of quantum gate that cycles the Paulis

2 votes
1 answer
63 views

Why is Bernstein-Vazirani guessing considered a one guess?

2 votes
1 answer
28 views

Converting a Matrix to a Gate in OpenQasm 2

0 votes
1 answer
136 views

How would you draw the phase-estimation circuit for the eigenvalues of $U = \mathrm{diag}(1,1,\exp(\pi i/4),\exp(\pi i/8)) $?

4 votes
0 answers
64 views

Universality with Toffoli + Hadamard

1 vote
1 answer
40 views

How to prove that the distillable entanglement satisfies $E_D(|\psi_d\rangle\!\langle\psi_d|)\ge \log d$?

1 vote
1 answer
26 views

What are the antisymmetric terms in $\sigma_{mn}$ in the expression for the Fisher information?

1 vote
1 answer
31 views

Controlled unitaries in quantum singular value transformation

0 votes
1 answer
56 views

Qiskit primitives with commuting observables

0 votes
1 answer
43 views

The amount of clbit arguments 0 does not match the instruction expectation (16)

4 votes
0 answers
32 views

How to benchmark approximate random unitary sampling

1 vote
1 answer
59 views

How is the depth of a circuit creating "Constant size vector states" $O(\log b)$

2 votes
1 answer
44 views

Grover, Qiskit, general definition of "good state"

1 vote
1 answer
45 views

What are the differences between the two Estimator in the qiskit


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