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Confusion regarding the definition of state of a qubit

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how to write electron spins using bra-ket notation?

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

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Why do we need Entanglement?

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

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

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

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

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

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Gottesman-Knill theorem -- last measurement step

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

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

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

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

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Cody Payne
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Quantum algorithms and binomial distributions and probabilities

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

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Craig Gidney
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Can we rearrange terms in the tensor product?

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

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How to create a multicontrol mcx gate or operation in cirq

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Where can I find tutorials on quantum variational algorithms?

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

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

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

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

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Unitary matrix knowing input and ouput states

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

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

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

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Martin Vesely
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How does VQE work?

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Tristan Nemoz
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Need help to understand topological color codes

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

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How to convert a basic matrix into a quantum circuit?

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

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

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Name of quantum gate that cycles the Paulis

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Eric Kubischta
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Why is Bernstein-Vazirani guessing considered a one guess?

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Converting a Matrix to a Gate in OpenQasm 2

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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)) $?

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Universality with Toffoli + Hadamard

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

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

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Quantum Mechanic
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Controlled unitaries in quantum singular value transformation

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Nikita Nemkov
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Qiskit primitives with commuting observables

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

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How to benchmark approximate random unitary sampling

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

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Tristan Nemoz
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Grover, Qiskit, general definition of "good state"

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Cryoris
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What are the differences between the two Estimator in the qiskit

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