Plans for the week of April 20-24

Dear all, welcome back to FYS5419. We hope you had a great weekend.? This week we will not have a regular lecture. The lecture will be recorded and uploaded (hopefully during Wednesday, Morten is away for a workshop).? ?Note also that exercise/project session is moved to 10.15-12, instead of 815-10. Carl Fredrik will be there for the project/exercise session.?

The recording will contain a discussion of the QAOA method with applications. The jupyter-notebook, located at https://github.com/CompPhysics/QuantumComputingMachineLearning/blob/gh-pages/doc/pub/week13/ipynb/week13.ipynb, contains the following material:

Part Focus Problem class

I ¡ª Foundations Theory from QUBO to quantum circuits, gradient methods, QML MaxCut on the 4-cycle?

II ¡ª Physical Realisation Two-electron double quantum well as a two-qubit QAOA processor MAX-CUT on a single edge

III ¡ª Financial Applications Portfolio optimisation via QUBO/Ising/QAOA + QNN S&P 500 stock selection

The application to financial data may be of interest for those of you who would like to apply quantum computing methods to financial data. The code there is based on the codes from part 1 and 2 above. Part 2 is a modification of a recent scientific paper where a two-qubit system for point defects was used to study? simulate experimentally the MAXCUT algorithm.? The modification is that the point defect is replaced by quantum dots with spin degrees of freedom only. Feel free to use these codes if this is of interest for project 2. If you spot errors/bugs etc with the codes, please let me know.

The PDF file at https://github.com/CompPhysics/QuantumComputingMachineLearning/blob/gh-pages/doc/pub/week13/pdf/week13.pdf contains the mathematical derivations which will be discussed during the lecture.

The jupyter-notebook contains also a comparison (for the financial data) with a quantum neural network (a code I wrote last year). The codes have been tested and updated (figures in particular) with Claude-code and should run without bugs.? The quantum neural network part will be discussed next week. Thus, the notes this week (and we will most likely keep discussing the QAOA next week as well) serve as a bridge to quantum ML methods, which will keep us busy for the rest of the semester.

Else, some of you are still looking for partners for project 2. Feel free to reach out to Kate at catherine.hughes@fys.uio.no

Best wishes to you all,

Carl Fredrik and Morten