Unanswered Questions
588 questions with no upvoted or accepted answers
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Getting Bond Dimension in qiskit Matrix Product State Simulation
I am setting up some circuit simulation in qiskit_aer using the MPS method. I am performing exact simulation (important for this task specifically). I am using the following setup:
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VQE for Max-Cut: Low Approximation Ratio (0.2 - 0.5) Instead of Expected 0.7 - 0.9
I am working on implementing a Variational Quantum Eigensolver (VQE) to solve the Max-Cut problem. I am using the approximation ratio (AR) as the metric to quantify the results, which is typically ...
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How to use Qiskit translation pass manager with Clifford + T gate basis?
Context
In qiskit, the translation stage of the transpilation "translates (or unrolls) the gates specified in a circuit to the native basis gates of a specified backend." (cf doc)
For that, ...
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What is the difference between `HighLevelSynthesis` and `UnrollCustomDefinitions` qiskit transpilation passes?
The doc for UnrollCustomDefinitions indicates :
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VibrationalStructureProblem in Qiskit with PySCF
I am looking for some example code that solves the Vibrational Structure Problem in Qiskit using PySCF driver (not Gaussian) using a recent version of Qiskit (1.2 or 1.3), preferably with UCCSD ansatz....
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Trying to run a VQE problem on Qiskit runtime
I am trying to find the ground state of a LiH molecule using qiskit runtime instead of the Estimator primitive. I am basically using the exact code given in the documentation here as a trial. But ...
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Are there any limit in the number of mid-circuit measurements when running a circuit on IBM QPU?
I am struggling to run circuits on IBM quantum hardware. Is it possible that my circuit is overcoming some limits in the number of mid-circuit measurements per qubit? Actually, I am asking for ...
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Is there a standard approach to measure T2 time?
I saw that different ion trap quantum computer manufacturers have given their own T2 (dephasing) times, but it is not clear whether they are obtained by the same test steps.
My question is: Is there a ...
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Understanding Phase Maps and Dephasing in a Periodically Driven Qubit System
I am working on a periodically driven qubit system and trying to understand the concepts of phase maps and dephasing. Here is the setup:
The initial qubit state is given by:
$\cos(\theta/2)|0\rangle+\...
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32
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Fake Backend, real backend vs aer simulator results
I initialised a circuit that creates a random state and then performed some calculations.
I dont change the state and perform repeated calculations using that state. I get a singular value around 0.25 ...
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Would it be possible to solve an linear programming problem with quantum computing, obtaining the same result as in an solver
So, I've begun viewing quantum computing out of curiosity and I have been studying linear programming in my university. I have heard that quantum computing can do linear programming equations, and I ...
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QuantumKernel command has been changed and construct_circuit is no more useful. What can I use instead?
Basically old qiskit-machine learning had QuantumKernel a class that did all the work.(feature_map, traning_parameters, construct_circuit, evalute etc.). However, it's been seperated and changed as ...
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Add Probability/Chance of measuring qubit to qiskit circuit drawing
I am new to using Qiskit to design quantum circuit. My prior experience has been to use Quirk Example to simulate and analyse circuits.
One feature that I really like about Quirk is it's ability to ...
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I have trouble using the alternatives for some commands in older versions of qiskit
I have a code that calculates the transition amplitute between and using the ZZFeatureMap with 4 repetitions and default data mapping function. Use the qasm_simulator with shots = 8192, seed_simulator ...
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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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