In the early days of quantum mechanics it has become clear that the exponential growth of dimension of Hilbert space required to describe a quantum system prevents us to do ab-initio calculations. Feynmann suggested solving this problem by using quantum systems for this type of calculations, which aimed at determining e.g. ground state properties of a quantum mechanical object.
In this seminar presentation a simple quantum computer “program” a phase estimation procedure is outlined and applied to solve standard quantum-mechanical problems.
To conclude the algorithm we analyze two different methods, that are originated from very different types of applications and construct, a third, a new one, unifying useful properties of the former methods.
Our final purpose is to explain the new algorithm, to show similarities and differences, compared to the earlier ones on the simple model example of a harmonic oscillator and radial hydrogen atom.
https://journals.aps.org/pra/abstract/10.1103/PhysRevA.78.022337
http://nils.web.elte.hu/QComQSim/index.html