Questions tagged [variational-quantum-algorithms]
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38 questions
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Why does my hybrid CNN-VQC model predict only one class on my medical imaging dataset?
I'm working on a hybrid quantum-classical neural network that augments a classical CNN with a variational quantum circuit (VQC) for image classification for a medical image dataset.
Model architecture ...
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AlgorithmError: 'The primitive job to evaluate the energy failed!'
i used code from below and getting error like AlgorithmError: 'The primitive job to evaluate the energy failed!' i need help regarding this, i was trying to calculate binding energy of deuteron by ...
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controllable approximation to an arbitrary unitary matrix
What is the optimal gate structure for a quantum circuit on N qubits to controllably approximate an arbitrary (2^N x 2^N) unitary matrix, having as few number of total (gate) parameters as possible ?
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understanding the Ansatz in VQC, QML
My question is specifically about VQC and the working of Ansatz. Let me put my understanding first: Data values of classical dataset are encoded into the qubits using angle encoding (I used ...
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Question on a research paper for solving the Poisson equation using a variational quantum algorithm
I am reading a research paper: "Variational Quantum Algorithm Based on the Minimum Potential Energy for Solving the Poisson Equation". [ArXiV]
In the paper, the authors try to solve the ...
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How to map expectation values to continuous values [closed]
I am attempting to do a variational quantum algorithm where the circuit is parameterized with ${\theta}$ and then I calculate the expectation value of the qubit, plug it in a cost function and then an ...
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motivation behind using PQCs in QML and Variational Algorithms
Parameterized quantum circuits (PQCs) are a key component in many quantum machine learning (QML) and variational quantum algorithms, such as the Variational Quantum Eigensolver (VQE) and quantum ...
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Error code 1217: "Session has been closed"
I am currently studying algorithms related to VQA. I have built a circuit to calculate the cost function and optimized it using a classical optimizer. During the initial optimization iterations, ...
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Implementation of identity block initialisation strategy for mitigating barren plateaus
I have been trying to implement this paper on identity block initialisation strategy for barren plateau mitigation but I don't really understand how one would apply it to a parameterised circuit with ...
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VQLS behaves badly under simulation with noise
I was studying VQLS in https://qiskit.org/textbook/ch-paper-implementations/vqls.html and since I could not understand the circuit created by the new Hadamard test (...
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Truncated Qumode States and Support
I am currently running numerical simulations of a single qumode state acted upon by a parameterised unitary. The qumode state is realised as a Fock state with a fixed cutoff dimension $(d)$ and is ...
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What's the case when parameter-shift rule does not hold?
When the parameterized unitary is of the form $e^{-i\theta V}$, where $V$ is a Hermitian operator of the unitary, we can use parameter shift rule to calculate the gradient.
In this paper, it says: &...
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Why EfficientSU2 in QGAN
In Qiskit's QGAN example, the parameterised quantum circuit to be trained is the EfficientSU2. I have not found any citation there on the choice of this circuit, and the only justification is that it ...
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Pennylane variational classifier demo - need for padding
In the variational classifier demo from Pennylane, the data loading is performed with
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Is there a way I can create an ansatz such that the number of 1 is same in all the superposition states? [duplicate]
So I am working with a variational quantum algorithm and I realised that it would be very beneficial if I could create an ansatz where all the states in the superposition have same numbers of 1s. For ...
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Image classification using quantum variational circuit?
Image classification using variational quantum circuit is described in here.
3 image clusters having clearly separable 3 feature coordinates have been chosen to be:
There are classical clustering ...
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an issue with the execution time of a VQC classifier on an IBM quantum machine
I tried to use the available open-source IBM quantum machines. I’m trying to do a classification using the VQC classifier to classify data, but I encountered a problem. The VQC keeps fitting on the ...
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Getting High cost function in code implementation of VQLS pennylane tutorial
I am currently trying to implement the tutorial in pennylane
https://pennylane.ai/qml/demos/tutorial_vqls.html
for very complex example in 3 Qubit and cost function is very high in spite of adding ...
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How are the parameters in a variational circuit optimized?
I'm quite new to QML and I don't understand how the parameters in a variational circuit are optimized.
I read about the parameter shift rule but what happens after the gradient is calculated ? How do ...
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