Research
Theoretical Particle Physics. Standard Model and Beyond from Numerical simulations
My research is in the field of theoretical particle physics, in particular on the strong interaction, the force that binds the quarks together in the hadrons. We call it strong interaction because at low energy the force is very strong and standard techniques such as perturbation theory cannot be applied.
I use "Lattice QCD", which was introduced by Kenneth Wilson in 74. QCD stands for QuantumChromoDynamics, the theory which describes the strong interaction in the Standard Model.
What Wilson proposed is to formulate the theory on a discrete euclidean space-time, the lattice, and then "solve it" through numerical simulations (Markov-Chain Monte-Carlos).
It allows to compute fundamental quantities (quark masses, hadronic matrix elements, coupling constant) from "first principles".
It has many theoretical advantages: it ts mathematically well defined, the path integral is regularised, gauge invariance is exact, etc. Also, it's fun to do !
However it is numerically very demanding: it requires High Performance Computing and very involved algorithms.
Lattice QCD is the main tool I use but physics-wise I have several research interests:
In the light quark sector, I work on kaon decays and kaon oscillations, related to matter-antimatter asymmetry.
I compute the Standard Model and the Beyond-Standard Model contributions.
See our last paper here https://link.springer.com/content/pdf/10.1007%2FJHEP11%282016%29001.pdf.
We did a press release with PU, should be accessible to a more general public
https://www.plymouth.ac.uk/news/ground-breaking-research-could-challenge-underlying-principles-of-physics
I also work(ed) on heavy quarks (heavy-quark effective theory for B-mesons ) and in the charm sector, mainly in the context of heavy-quark effective theory.
Since 2014 I work on the sign problem, which is not only relevant for high-energy-physics but for several areas of sciences, in particular condensed-matter.
With Kurt Langfeld, we study a system of heavy quark at finite density and low temperature, using a method based on a density-of-states approach.
We showed recently that we can solve the sign-problem for this theory for a whole range of density, in particular in regions where the sign problem is severe.
We are now applying to full QCD at finite density on a small volume as a proof of concept
Since last year, I have also started to work on nuclear physics with the California Lattice (CalLat) Collaboration.
Key words: Lattice QCD, Kaon physics, epsilon'/epsilon, BSM neutral kaon mixing, CP violation, B mesons, HQET, Non-Perturbative renormalisation, Sign problem, Heavy-Dense QCD
A list of recent talks I gave
06/2017, Granada: "Fierz transformations and q-slash schemes for BSM operators"
(Lattice conference)
05/2017, Glasgow. Seminar: "Solving the sign problem for heavy-dense QCD, a density-of-states approach"
05/2017, Paris. Workshop: "QCD at finite chemical potential"
04/2017, Marseille. Workshop. "K->pipi, CP violation and neutral kaon mixing"
03/2017, Liverpool. Seminar. "Kaon decay and mixing, within and beyond the standard model"
List of publications:
https://inspirehep.net/search?ln=en&p=f+a+garron%2C+n&of=hb&action_search=Search&sf=earliestdate&so=d