Quantum Computing

Credit: Stephen Shankland/CNET

Quantum machine learning for particle track reconstruction (arXiv:2212.07279)

This paper presents a hyrbid classical-quantum machine learning algorithm towards reconstructing particle trajectories at the High Luminosity Large Hadron Collider. It proposes a classical support vector machine (SVM) with a quantum-estimated kernel and uses this to classify a set of three hits (triplets) as either belonging to or not belonging to the same particle track. The performance of the algorithm is then compared to a fully classical SVM. When compared to the fully classical SVM, the quantum algorithm shows an improvement in accuracy for the innermost layers of the detector that are expected to be important for the initial seeding step of track reconstruction.

A quantum walk approach to parton showers (arxiv:2109.13975)

This paper presents a novel quantum walk approach to simulating parton showers on a quantum computer. We demonstrate that the quantum walk paradigm offers a natural and more efficient approach to simulating parton showers on quantum devices, with the emission probabilities implemented as the coin flip for the walker, and the particle emissions to either gluons or quark pairs corresponding to the movement of the walker in two dimensions. A quantum algorithm is proposed for a simplified, toy model of a 31-step, collinear parton shower, hence significantly increasing the number of steps of the parton shower that can be simulated compared to previous quantum algorithms.

Towards a Quantum Computing Algorithm for Helicity Amplitudes and Parton Showers (arxiv:2010.00046)

This paper proposes general and extendable algorithms for quantum gate computers to facilitate calculations of helicity amplitudes and the parton shower process. The helicity amplitude calculation exploits the equivalence between spinors and qubits and the unique features of a quantum computer to compute the helicities of each particle involved simultaneously, thus fully utilising the quantum nature of the computation. The parton shower algorithm simulates collinear emission for a two-step, discrete parton shower.