Questions tagged [qaoa]
For questions about the Quantum Approximate Optimization Algorithm (QAOA), first introduced in Farhi, Goldstone, Gutmann 2014 (https://arxiv.org/abs/1411.4028).
148
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Converting Ising Hamiltonian to a Circuit in Qiskit
I tried to solve a 2-node TSP (travelling salesman problem) by implementing QAOA on Qiskit. The graph looks like:
Then I used the related Qiskit functions to convert the graph to the QUBO and map it ...
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32
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Building a problem unitary circuit for QAOA on Qiskit
I am trying to build a circuit for QAOA that solves a Traveling Salesman's Problem, which can be represented as a complete graph with 4 nodes. After formulating the problem as a QUBO and mapping it ...
- 159
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How are edge weights "loaded" in the problem hamiltonian when solving TSP with QAOA?
I've come across several of the QAOA tutorials, and yet I'm afraid I haven't found any explanation on this. According to the Qiskit tutorial on QAOA, the cost function for the target problem has a ...
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Qiskit QAOA optimization does not work when setting simulation seed in AerSampler
I am using Qiskit's QAOA for optimization and I would like to extract the probabilities distribution obtained in the optimization loop when running the circuit with the optimal parameters set. To do ...
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Implementing Adiabatic Grover Search via QAOA
I am reading the paper Grover Search Inspired Alternating Operator Ansatz of Quantum Approximate
Optimization Algorithm for Search Problems. The paper proposes running the Adiabatic Grover Search ...
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IS my QUBO too big for QAOA using IBM Quantum computer?
On qiskit, I have defined a QUBO, called qp as follows:
...
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65
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QAOA on weighted graphs
I tried to use the QAOA to solve the MaxCut problem on a 10 nodes weighted graph and run the simulation on qiskit from $p = 1$ to $p = 6$. I was expecting to get closer to the real solution as $p$ ...
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Link between AQC and QAOA
I try to understand precisely the link between AQC and QAOA, through the Trotter-Suzuki formula.
A similar question is Derivation of QAOA from AQC, but I was asked by moderators to post my question ...
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How to add a circuit layer after computing QAOA layer
I have used the Qiskit-based QAOA function to solve a combinatorial problem tsp, and I want to append a circuit after the QAOA layer, is there any way to do that?
Qaoa
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How to tune QAOAAnsatz when solution is known to have a certain form?
I'm running QAOAAnsatz in QisKit, and I know that the solution to my problem has a certain form. Namely:
...
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55
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How to change the simulator used by Qiskit's `QAOA` (or get around the "Maximum allowed dimension exceeded" error)?
I'm running MinimumEigenOptimizer with QAOA on a large quadratic program:
...
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How to use Warm-Start QAOA in QisKit to solve non-convex QUBO problem?
I have a non-convex QUBO problem that I'd like to solve by warm-starting QAOA with a solution obtained from a continuous relaxation solution obtained by a classical algorithm. The specifics of the ...
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Recent experimental demonstrations of variational quantum algorithms?
I am interested in the recent experimental demonstrations of variational quantum algorithms.
Can someone please provide me with a list of references of recent experimental demonstrations of ...
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28
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'Continuous' (Classical) Cost function for QAOA
I have some combinatorial optimization problems which I would like to analyze using QAOA. These problems are coming from various applications in scientific computing such as solving PDEs. Some of ...
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91
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How to get angles optimized by classical optimizer from QisKit's QAOA Module?
I have the following simple optimization in QAOA:
...
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65
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QAOA algorithm from qiskit.algorithms.minimum_eigensolvers sends jobs without stopping
I don't know why the code keeps sending jobs. The code is:
...
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1
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49
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Portfolio optimization via quantum Zeno dynamics in Qiskit
Recently, I came across paper Portfolio Optimization via Quantum Zeno Dynamics on a Quantum Processor. In the paper, a new approach to optimization with QAOA is introduced. Instead of employing a ...
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How to sanity check QAOA cost Hamiltonian?
I'm trying to learn QAOA and how to apply it to a complex combinatorial problem. But for the purpose of this question I'll use the common example
MaxCut.
I'd like to know if I've set up my cost ...
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149
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Does QAOA require that the problem Hamiltonian be an Ising Hamiltonian as a quadratic function of the spin variables?
In the context of QAOA, I often see the problem Hamiltonian being called an "Ising Hamiltonian", and shortly after, I that the Hamiltonian is a quadratic function of the spin variables.
Is ...
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Does QAO Ansatz have any better performance guarantees than QAOA?
QAOA is a well-known heuristic for solving optimization problems, and it has the desirable property that as p -> infinity, the true minimum objective function value is reached.
There is a ...
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Combinatorial optimization problems solving using VQE
I'm studying about the variational quantum algorithms and I would like to know about the usage of VQE for solving combinatorial optimization problems.
VQE can find the ground state energy of a given ...
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Can we easily find the ground states for one-dimensional ANNNI-like Ising models?
The Hamiltonian for a simple one-dimensional Ising model on a finite (linear) chain of $L$ spin-half particles might be:
$$H = -J \sum_{i=0}^{L-1} \sigma_i^z \sigma_{i+1}^z.\tag{1}$$
The interactions ...
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4
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Probability inequality for Quantum Approximate Optimization Algorithm (QAOA)
In arXiv:2207.14734 the authors claim that it is "straightforward to show that" their equation 8 holds:
$$\mathrm{Pr}_{x\sim q}[x:f(x)\geq \mu] \geq \frac{1}{M}$$
where we have an objective ...
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Variational Quantum Algorithms for Graph Traversal
I have a combinatorial optimization problem which on a first pass I think boils down to finding a path with a maximal score. The score for a path is computed by an auxiliary function.
Are there near-...
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Derivation of QAOA from AQC
In adiabatic quantum optimization we start with an initial Hamiltonian $H_0$ and then adiabatically evolve from $H_0$ to $H_P$ (problem hamiltonian) for a time $T$ according to
\begin{equation}\label{...
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18
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Maximize the Sum of absolut Vector elements with QAOA
Im trying to get started with QAOA. I tried to program a simple example for testing my understanding. The goal is to maximize $z^TV$ with $V \in \mathbb{R}^{nx1},z \in ${$-1,1$}$^n$. I tried ...
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55
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Using BFGS for MAXCUT
In the original Qiskit QAOA implementation, the sample uses COBYLA as the classical optimizer in the following code segment:
...
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36
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Qiskit: The parameters of the circuits constructed by QAOAAnsatz will change after decomposition and transpilation
When I submit a parametrized circuit as an input for the mixed operator in QAOAAnsatz, some strange results appear.
For example, when I submit a parametrized ...
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59
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Custom Mixer for QAOA for Graph Coloring, where to start?
I am trying to implement QAOA for graph coloring with hard constraints. In this paper, eq. 9 a custom mixer is proposed, is looks like this:
$B_{ui} = \frac{1}{2^{l + 1}}(X_{u0}X_{u1} + Y_{u0}Y_{u1}) \...
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60
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Applying horizontal dots in a LaTeX Quantum Circuit diagram [closed]
I am almost done with my circuit diagram for the QAOA circuit but the \cdots does not want to cooperate. As seen there exists some wire drawn across the dots from the gate to the right and I can't ...
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124
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Finding the minimum cut using QAOA
I am trying to find the minimum cut for a given graph. I am using QAOA and refering to the qiskit textbook: https://qiskit.org/textbook/ch-applications/qaoa.html. I understand I need to find the ...
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1
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59
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What happened to the 1/2 in the MAXCUT Problem Unitary for QAOA
I recently started to begin with QuantumComputing following the Qiskit tutorial. I worked through the basics and now reached Chapter 4.1.3 (https://qiskit.org/textbook/ch-applications/qaoa.html).
I ...
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Commutativity of XY gate
My question is a simple one: Can 2 XY gates commute ?
XY gate is a 2-qubit XX+YY interaction also sometimes referred to as iSwap gate.
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1
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143
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Implementation of QAOA to solve version of knapsack problem
Say I want to fill a knapsack with as many things as possible. I don't care about what they are, simply the number. But I don't want the total weight to exceed a set limit.
[https://qiskit.org/...
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1
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441
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QAOA MaxCut IBM Qiskit Example
I tried using the same example of Qiskit MAX-CUT problem for a different graph.
https://qiskit.org/textbook/ch-applications/qaoa.html
My graph is as follows:
Using COBYLA I get a cut which is NOT a ...
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1
answer
257
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Implementing QAOA Hamiltonian for MAX-3-SAT in Qiskit
I have read about how QAOA is used to tackle the MAX-CUT problem and wanted to test my understanding by trying to implement some code to approximate the MAX-3-SAT problem.
To do so, I considered the ...
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1
answer
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Calculating state fidelity and space complexity of Minimum Eigen Optimizers (VQE, QAOA and Grover Optimizer) in qiskit
I'm a beginner in using Qiskit and my Computer Science background is not extensive. But I understand the Quantum Physics aspects of it relatively well.
I solved a QUBO problem in Qiskit using VQE (...
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0
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118
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Interpreting VQE and QAOA based solutions in portfolio optimization
I am going through portfolio optimization using Qiskit. It really looks interesting. The module has both VQE and QAOA algorithms for optimizing the portfolios.
In the VQE based solution the ...
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Error analysis on the approximation of an adiabatic evolution operator by a QAOA circuit
I would like to know what would be the approximation error of a QAOA circuit.
Suppose we have time-dependent Hamiltonian $H(t) = (1 - s(t))H_{init} + s(t)H_{prob}$ where $H_{init}$ in an initial ...
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Does the Lie closure of a set of Hamiltonians describe all unitaries you can generate with them?
Suppose we have $k$ Hermitian matrices $H_1, ..., H_k \in M_d(\mathbb{C})$. Define $\mathfrak{g} = \langle iH_1, ... iH_k \rangle_{\text{Lie}}$ to be the Lie algebra generated by these Hermitian ...
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241
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Qiskit unable to transpile the circuit for Rigetti Aspen M 1 on AWS
I am trying to run a Qiskit QAOA algorithm on AWS Rigetti Aspen M 1 Backend using qiskit braket provider. However qiskit is not able to properly transpile the circuit
...
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For the same operator, when I use qiskit's VQE and QAOA solutions, the results are completely different
Specifically, I can't get the correct result using QAOA，A total of 6 qubits were used in this work，this is part of my code using VQE and QAOA
localsim = BasicAer.get_backend('qasm_simulator')
...
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1
answer
423
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Choosing a different optimizer when running QAOA in qiskit
I am trying to reproduce the QAOA example from https://qiskit.org/textbook/ch-applications/qaoa.html and learn how to opt for a different optimizer.
The relevant block in the example is (towards the ...
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2
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269
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qiskit qaoa.compute_minimum_eigenvalue
I am having some trouble running the compute_minimum_eigenvalue method from qiskit's QAOA: the documentation states that one ...
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1
answer
50
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Validating existing QAOA, deprecated solutions on qiskit
I'm currently evaluating a static QC, QML and QAOA approach to solving a combinational problem. My solution with the static QC and QML approach is finished, and all data has been collected.
Now, the ...
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2
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464
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Qiskit compute mean expectation value
I want to calculate the mean expectation value of an PauliSumOp within qiskit after I executed a QAOA Circuit. My approach is the following:
...
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1
answer
100
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Understanding QAOA from Basics/scratch
Recently after working on QAOA with finance and graph coloring problems. I have started exploring the QAOA from scratch. I would like to understand the QAOA derivation mathematically and have started ...
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138
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What are the important parameters when it comes to VQE algorithms in qiskit?
So I wrote an algorithm for a quadratic problem (qubo) and try to solve it. My question is why I don't get the correct results when running my algorithm on a quantum computer like IBM_manila. In the ...
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2
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415
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Why do we decompose the hamiltonian into Pauli strings to measure the expectation value?
Measuring the expectation value of a hamiltonian is an essential step in some algorithms like QAOA.
I noticed that the procedure always starts with decomposing the hamiltonian into a sum of Pauli ...
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Why does QAOA's performance monotonically increase as p increases?
From A Quantum Approximate Optimization Algorithm - Farhi et al.
The Quantum Approximate Optimization Algorithm has the key feature that as
p
increases the approximation improves. We contrast this to ...
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