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Top Questions

4 votes
2 answers
1k views

Is quantum teleportation fully secure (in principle)?

5 votes
2 answers
59 views

Reasonable Circuit Depth

2 votes
2 answers
272 views

Why is an X gate a quantum coin flip?

2 votes
2 answers
156 views

Matrix representation of SWAP on two qubit registers?

5 votes
2 answers
52 views

What's the most efficient decomposition in terms of T-count of the 4-qubit Toffoli with 1 ancilla?

3 votes
1 answer
108 views

Show that $E_k=(I\otimes\langle e_k|)U(I\otimes|e_0\rangle)$ implies $U=\begin{bmatrix}[E_1]&\cdots\\ [E_2]&\cdots\\\vdots&\ddots\end{bmatrix}$

2 votes
1 answer
92 views

How can I see the circuit that was actually executed on the device in pennylane?

3 votes
1 answer
57 views

How to simulate rectangular surface code with stim?

2 votes
2 answers
69 views

Quasiprobability decomposition of the CZ-gate

2 votes
1 answer
66 views

Hilbert space vs RKHS

5 votes
1 answer
50 views

Action of a channel on an "unphysical" state

3 votes
1 answer
61 views

How do we compute quantum walks for a graph?

2 votes
1 answer
46 views

Solving a Bloch sphere where alpha is imaginary

1 vote
2 answers
50 views

Check if a Pauli string belongs to a stabilizer tableau

3 votes
0 answers
82 views

Thermodynamic Speed Limit to Quantum Computing

3 votes
0 answers
74 views

What other discrete non-trivial non-Clifford groups of gates are there?

1 vote
1 answer
32 views

Is there an alternative algorithm to extract a probability of states of qubit after measuring?

1 vote
0 answers
57 views

How to compute Haar average over the unitary group of a ratio of homogeneous polynomials?

0 votes
2 answers
24 views

Can I create a quantum circuit from a list of operations in pennylane?

1 vote
1 answer
38 views

Using entropy quantum computing for solving optimization problems

2 votes
1 answer
29 views

Is there an expression for the partial trace of a vectorized density matrix?

2 votes
0 answers
46 views

Entangling attack on BB84 protocol

1 vote
2 answers
45 views

How to calculate CNOT gate for three-qubit (1-control, 2-target) states as a matrix?

0 votes
0 answers
42 views

Stabilizers Of The H Code

0 votes
0 answers
41 views

How can the result of 1 million transformations on a qubit be verified to be correct?

0 votes
2 answers
39 views

What can I use instead of mct (multi-controlled Toffoli)? (Grover's algorithm)

0 votes
1 answer
38 views

Expectation values of non-local operators in Qiskit

0 votes
0 answers
37 views

About swap gate

2 votes
0 answers
33 views

Algorithm for finding Pauli stabilizers of a code

1 vote
1 answer
25 views

ModuleNotFoundError when running Qiskit RNG

0 votes
0 answers
31 views

Quantum measurement on Bloch Sphere

0 votes
1 answer
25 views

What is the structure of Qiskit's amplitude-encoded quantum circuit?

0 votes
1 answer
25 views

I was solving matrix of beam splitter in python but got stuck in understanding the library

0 votes
1 answer
19 views

How to get the matched nodes using Matching.decode() in PyMatching?

0 votes
0 answers
23 views

Understanding Shor algorithm fo Elliptic Curves Demonstration

1 vote
0 answers
23 views

Quantum algortihm for SVD and eigendecompostion

1 vote
0 answers
22 views

State tomography with Pauli basis measurements for a high number of qubits

0 votes
0 answers
21 views

Combine qubits together to get additonal accuracy

0 votes
0 answers
19 views

What does it mean for a Qiskit pulse to have a negative amplitude?

1 vote
0 answers
18 views

References discussing the carbon footprint expected for fault-tolerant quantum computers?

0 votes
0 answers
16 views

How to stretch duration of standard gates of an IBM Backend?

0 votes
0 answers
15 views

Deutsch Algorithm's matrix, what is the matrix? is there one? what is this oracle?

2 votes
0 answers
13 views

Lowest energy problem with additional constraints


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