Unanswered Questions
308 questions with no upvoted or accepted answers
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Is there a general circuit implementation for the commutation matrix?
The commutation matrix $K^{(r,m)}$ is defined by
$
K^{(r,m)} = \sum_{i=1}^r \sum_{j=1}^m (\boldsymbol{e}_{r,i} \boldsymbol{e}_{m,j}^T) \otimes (\boldsymbol{e}_{m,j} \boldsymbol{e}_{r,i}^T)
$
It also ...
- 565
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Procedure for constructing magic state gate injection gadgets
I have a quantum computer that cannot implement the gate $U$ by itself, and needs help in the form of a magic state $|U\rangle$ held in another register. Is there a general-purpose procedure for ...
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Custom Feature Map Error for VQR in Qiskit 'Input data has incorrect shape, last dimension is not equal to the number of inputs'
I am trying to use a VQR for solving a regression problem. My data has 5 features, I want to use 4 features to estimate 5th one. I made it work with ZFeatureMap but now I want to create my own feature ...
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Constructing Conditional Phase Shift in Grover's Algorithm and Optimality of Grover's Algorithm for Multiple Solutions
I’m currently working through some questions related to Grover's algorithm and need help with the following:
Conditional Phase Shift Construction using single qubits and two-qubits gate? Also, how ...
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How to get historical calibration data for mthree (M3) from IBM Quantum devices?
I'm using mthree in Batch mode. A batch needs to be queued before it can be executed. The time when a batch was executed can be obtained from the IBM Quantum Platform site, so I would like to obtain ...
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How to design quantum circuits to encode the ket to the phase?
Suppose we have a function $f:\{0,1\}^n \rightarrow \{0,1,2,\cdots,k\}$, and a unitary $U|x\rangle |0\rangle =|x\rangle|f(x)\rangle$ for $x\in \{0,1\}^n$. Now we want to design a quantum circuit from $...
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Reversible Two-Four-Three Swap
I'm trying to solve this. I'm very new to circuit-based reversible computing and have studied about gates. I'm trying to see how can I solve this.
As far as I've come, I see that I might need to put a ...
CommunityBot
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68
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How to apply circuit cutting to MCX gates?
I am working on a quantum version of a fuzzy controller (https://ieeexplore.ieee.org/document/9869303). This inference engine is implemented with a quantum circuit composed of X and MCX gates as in ...
- 61
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RuntimeJobFailureError: 'Unable to retrieve job result. Error code 1520; The instruction cost per qubit exceeds the system limit
I want to find two operands of multiplication result of 180. In another word, finding integer factors of 180.
I'm using ...
glS♦
- 26.9k
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Amplitude Amplification on subsystem of unknown entangled state
Consider we have a single copy of a state,
\begin{equation}
|\psi\rangle = b |0\rangle_{anc} \otimes |B\rangle_{tar} + g |1\rangle_{anc} \otimes |G\rangle_{tar}
\end{equation}
where the amplitudes $...
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A basic misunderstanding regarding a quantum algorithm for finding the maximum (Ahuja & Kapoor)
My question is regarding this paper where the authors claim that their algorithm finds the maximum in an unsorted table $T[0,...,N-1]$ of size $N$ in $O(\sqrt N)$ queries to the oracle. However, it's ...
- 3,493
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Classification in QSVM 2014 model: understanding the quantum circuit
This is a QSVM circuit from this paper (fig.. 1-e). I am having hard time understanding after barrier 2(in blue line).
I get that before line one, HHL is used to find the hyper-plane parameters ...
- 3,493
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How many times do I have to repeat the oracle + amplitude amplification in Grover's algorithm?
My question is: How many times do I have to repeat the oracle + amplitude amplification in Grover's algorithm?
For further info: I am using 13 qubits and the # of solution states is unknown (may have ...
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How does amplitude amplification work (in Grover's Algorithm) and does this code for it work?
I understand amplitude amplification at a high level: operations and gates are applied to the qubits such that the solution states amplitude is raised while the non-solution states are lowered. ...
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Understanding sources of error in 4-bit Grover's search on IBM QC
This question is similar to some others I've come across, related to why a 4-qubit implementation of Grover's search yields such poor results when run on the IBM QC compared to the 3-qubit case (...
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