QFitter -- A Quantum Fitting Framework Applied to Effective Field Theories

Abstract

The use of experimental data to constrain the values of the Wilson coefficients of an Effective Field Theory (EFT) involves minimising a χ 2 function that may contain local minima. Classical optimisation algorithms can become trapped in these minima, preventing the determination of the global minimum. The quantum annealing framework has the potential to overcome this limitation and reliably find the global minimum of non-convex functions. We present QFitter, a quantum annealing method to perform EFT fits. Using a state-of-the-art quantum annealer, we show with concrete examples that QFitter can be used to fit sets of at least eight coefficients, including their quadratic contributions. An arbitrary number of observables can be included without changing the required number of qubits. We provide an example in which χ 2 is non-convex and show that QFitter can find the global minimum more accurately than its classical alternatives.

String Model Building on Quantum Annealers

“…QA has been utilized in many simple settings, notably for solving network problems, but its application in high energy theory has up to now been somewhat limited (see refs. [21][22][23][24][25][26][27][28][29][30][31][32][33][34][35] for some examples). In the string setting, QA has been employed in hybrid algorithms, for example, most recently in Genetic QA [33,34] in which the GA performance is improved with a QA stage, however it has not to date been possible to implement a full string search directly on a quantum annealer (or indeed on a quantum computer of any kind).…”