Hottest Questions This Month

8

votes

2

answers

905

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What are magic states?

modified Sep 21 at 11:22 JSdJ 2,358

3

votes

3

answers

338

views

How can I create an arbitrary superposition state of two qubits in Qiskit?

qiskit programming

modified Sep 1 at 22:29 glS 11k

4

votes

2

answers

139

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Is there a circuit to compare two quantum states?

quantum-state circuit-construction tomography

modified Sep 21 at 22:22 Niel de Beaudrap 9,586

2

votes

2

answers

475

views

Is a 0 degree rotation around an axis meaningless?

quantum-gate

answered Aug 31 at 6:34 Martin Vesely 5,879

4

votes

3

answers

152

views

Prove that Shannon and von Neumann entropies satisfy $H(P)\ge S(\rho)$ with $P$ diagonal of $\rho$

measurement entropy information-theory

modified Sep 20 at 22:37 glS 11k

3

votes

2

answers

69

views

Decomposition of $|110\rangle \leftrightarrow |000\rangle$ Exchange Gate

qiskit gate-synthesis

modified Sep 9 at 7:05 Martin Vesely 5,879

3

votes

1

answer

138

views

Nielsen & Chuang Exercise 2.55: Prove that $\exp \left[ -\frac{iH(t_2 - t_1)}{\hbar} \right]$ is unitary

mathematics nielsen-and-chuang textbook-and-exercises

modified Sep 4 at 7:58 glS 11k

5

votes

2

answers

119

views

Is the square root of SWAP gate “maximally entangling”?

quantum-gate entanglement

modified Sep 3 at 17:08 forky40 688

2

votes

2

answers

146

views

Question regarding soundness bound in QMA versus QCMA separation

algorithm complexity-theory

modified Sep 23 at 9:30 glS 11k

0

votes

2

answers

145

views

How to initialise a qubit in the state $\frac{1}{\sqrt2}(|0\rangle+|1\rangle)$ in qiskit?

qiskit programming

modified Sep 18 at 11:05 glS 11k

4

votes

2

answers

106

views

What is the advantage of quantum machine learning over traditional machine learning?

machine-learning quantum-enhanced-machine-learning

answered Sep 8 at 12:54 Maria Schuld 31

2

votes

2

answers

78

views

when we specify quantum states in $\mathbb C^2$, why do we only have $2$ basis states?

bloch-sphere

modified Sep 9 at 12:33 glS 11k

3

votes

1

answer

93

views

Is the Clifford group finite?

clifford-group

modified Sep 9 at 20:41 glS 11k

-1

votes

3

answers

114

views

Google Colab - ImportError: The class MatplotlibDrawer needs pylatexenc

quantum-gate quantum-state qiskit circuit-construction

modified Sep 18 at 10:40 Oussama Rizwi 3

4

votes

3

answers

52

views

Bell state preparation

quantum-gate quantum-state tensor-product bell-basis

answered Sep 18 at 20:54 Abbyss 51

0

votes

1

answer

106

views

Command errored out with exit status 1 while installing the editable env for qiskit terra

qiskit programming

modified Sep 4 at 11:41 Mithrandir24601♦ 3,157

5

votes

1

answer

92

views

Circuit for VQE Expectation Value Finding

measurement vqe

modified Sep 11 at 19:00 Davit Khachatryan 3,028

4

votes

1

answer

116

views

Does this experimental discovery of anyons enables the topological quantum computer (e.g. Microsoft) to become a reality?

physical-realization topological-quantum-computing anyons

answered Sep 6 at 11:12 JSdJ 2,358

3

votes

1

answer

88

views

How to find the unitary operation of a depolarizing channel?

quantum-operation textbook-and-exercises unitarity kraus-representation

modified Sep 1 at 21:57 glS 11k

0

votes

1

answer

87

views

What is the matrix representation of the Hadamard gate in the computational basis?

quantum-gate textbook-and-exercises hadamard

modified Sep 21 at 19:42 Condo 386

3

votes

1

answer

103

views

How to implement linear combination of two unitary gates in a quantum circuit?

quantum-gate algorithm circuit-construction

modified Sep 16 at 6:39 DaftWullie 32.6k

-1

votes

1

answer

128

views

Implementing a circuit that returns $|01\rangle$ and $|10\rangle$ with equal probability

quantum-gate programming circuit-construction optimization random-quantum-circuit

modified Sep 15 at 16:13 glS 11k

3

votes

1

answer

77

views

Effect of quantum entanglement on measurement

quantum-state entanglement foundations

modified Sep 13 at 22:16 Sam Benet 41

3

votes

1

answer

84

views

Is there any 'official' list of errata for Nielsen & Chuang?

resource-request nielsen-and-chuang

answered Sep 8 at 17:28 Victory Omole 866

1

vote

1

answer

104

views

Where does $xy = a + b \pmod 2$ come from in the context of CHSH inequalities?

bell-experiment non-locality

modified yesterday Mithrandir24601♦ 3,157

1

vote

2

answers

80

views

Running Google Cirq example code from their webpage — where do I find information about PROCESSOR_ID?

programming cirq

modified Sep 18 at 11:03 glS 11k

4

votes

1

answer

130

views

+300

Proof using hybrid method that inverting a permutation requires exponential queries for BQP machines

complexity-theory oracles bbbv

modified yesterday Mark S 3,448

1

vote

1

answer

78

views

The commutativity of $I$ and $Y$ in a stabilizer code

stabilizer-code

modified Sep 1 at 10:25 M. Al Jumaily 578

1

vote

2

answers

100

views

Can I switch $\alpha_0$ and $\alpha_1$ conditionally to $\alpha_0>0$ in a state $\alpha_0|0\rangle+\alpha_1|1\rangle$?

quantum-operation superposition

answered Sep 1 at 7:10 tsgeorgios 126

4

votes

1

answer

59

views

Why isn't NV-center-based quantum computing mainstream?

physical-realization nv-centers

modified Sep 3 at 8:15 Jonathan Trousdale 2,223

1

vote

1

answer

57

views

What would be measured if you measure two entangled qubits at exactly the same time?

entanglement measurement

modified Sep 15 at 12:33 glS 11k

2

votes

2

answers

73

views

Generate a 3-qubit SWAP unitary in terms of elementary gates

quantum-gate qiskit circuit-construction

modified Sep 21 at 15:40 Davit Khachatryan 3,028

0

votes

1

answer

92

views

What is the output of applying the Hadamard matrix to $\sum_{y\in\{0,1\}^n} (-1)^{xy}|y\rangle$?

textbook-and-exercises hadamard

modified Sep 11 at 15:33 Mithrandir24601♦ 3,157

2

votes

2

answers

55

views

Having trouble finding angles for Bloch vector

qiskit mathematics textbook-and-exercises

modified Sep 18 at 11:10 glS 11k

2

votes

1

answer

106

views

How to measure in another basis

qiskit programming circuit-construction measurement

modified Sep 7 at 6:45 Martin Vesely 5,879

3

votes

1

answer

50

views

CNOT expressed with CZ and H gates by taking into account HZH =X

quantum-gate gate-synthesis pauli-gates

modified Sep 21 at 16:57 glS 11k

1

vote

1

answer

64

views

Nielsen & Chuang Exercise 2.32: Show that the tensor product of two projectors is a projector

mathematics nielsen-and-chuang textbook-and-exercises

answered Aug 29 at 6:58 DaftWullie 32.6k

4

votes

1

answer

80

views

Is the Haar measure invariant under conjugation?

mathematics unitarity haar-distribution

modified Sep 7 at 22:47 dmitryk 41

3

votes

1

answer

62

views

How can we only use 8192 shots for an experiment with 14 or more qubits?

quantum-gate quantum-state ibm-q-experience measurement

modified Sep 10 at 11:46 glS 11k

1

vote

1

answer

57

views

How do quantum gates work on qubits in the physical world?

quantum-gate quantum-state physical-qubit

modified Sep 1 at 22:29 glS 11k

2

votes

1

answer

69

views

Can local projections increase entanglement?

quantum-state entanglement quantum-operation

modified Sep 23 at 12:23 glS 11k

3

votes

1

answer

52

views

Implement U2 and U3 gate in Q#

quantum-gate programming q#

modified Sep 9 at 20:46 glS 11k

1

vote

2

answers

64

views

quantum random number generator implementation in quantum lab

qiskit ibm-q-experience

modified Sep 18 at 6:51 Martin Vesely 5,879

3

votes

2

answers

49

views

Can Alice and Bob distinguish entangled state coefficients?

quantum-state entanglement measurement density-matrix

answered Sep 16 at 7:09 DaftWullie 32.6k

2

votes

1

answer

38

views

IBM Melbourne quantum computer performance and errors

ibm-q-experience measurement ibm error-mitigation

modified yesterday Martin Vesely 5,879

2

votes

1

answer

79

views

Is this a Bell test?

qiskit entanglement bell-experiment

modified Sep 10 at 11:48 glS 11k

1

vote

2

answers

37

views

Relation between trace distance and inner product between pure states

textbook-and-exercises trace-distance

modified Aug 31 at 9:32 glS 11k

1

vote

2

answers

37

views

How to execute many circuits on an IBMQ backend?

qiskit programming ibm-q-experience

modified Sep 18 at 11:08 glS 11k

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