Work Experience

Author

Simone Romiti

Expertise Summary

Computational Methods:

  • Monte Carlo algorithms for multi-dimensional integrals: Euclidean path integral
  • Bayesian algorithms: Hybrid Monte Carlo, Nested Sampling, Model Averaging
  • Machine Learning: PINNs, VAEs, diffusion models

Physics Areas:

  • Precision lattice phenomenology, hadronic contributions to muon anomalous magnetic moment
  • Transition Form Factors of pseudoscalar mesons (\(\pi^0, \eta, \eta'\))
  • Isospin breaking effects on the lattice
  • Hamiltonian formulations on the lattice (Kogut-Susskind), Quantum Computing, solution of Schrödinger equation on truncated Hilbert spaces

Technical Skills:

  • High-performance computing (HPC): CPU and GPU parallel computing, Data Structures and Algorithms
  • Open-source software development: git version control, CI/CD, DevOps
  • Collaboration leadership and project management
  • Cross-disciplinary research integration

Work positions

April 2024 – present · University of Bern, Switzerland

Department:
Institute for Theoretical Physics, Albert Einstein Center for Fundamental Physics (AEC)

Key Activities:

  • Machine Learning applications:

    • Independently developed Physics-Informed Neural Networks (PINNs) method for solving eigenvalue problems in \(\mathrm{SU}(N)\) lattice Hamiltonians | overcoming Hilbert space truncation exponential scaling

  • Hadronic contributions to muon \((g-2)_\mu\):

    • Hadronic Vacuum Polarization (HVP) calculations for \(u,d,s,c\) flavors and Leading Isospin Breaking corrections. I am the reference person for the Bern group in the ETM collaboration’s blinded HVP analysis.
    • Hadronic Light-by-Light (HLbL) scattering: implementation and calculation of meson pole contributions. I am the contact person for the pole contributions and the analysis tool chain.
    • Generation and tuning of ETMC gauge configurations at the physical point, used for the HVP and HLbL contributions.
    • Represented the collaboration at the 2025 \((g-2)_\mu\) Initiative workshop and am included in the author list of the 2025 \((g-2)_\mu\) Whitepaper.

  • Transition Form Factors (TFFs):

    • Principal Investigator for CSCS computing time allocation of 240k GPU node hours, for the calculation of \(P\to\gamma^*\gamma^*\) transition form factors for \(\eta,\eta'\) mesons: continuum limit over the ETM ensembles.

  • Numerical developments:

    • Developed open-source implementation of pseudoscalar meson pole contributions (infinite and finite volume)
    • Advanced work on precision lattice QCD at sub-permille level
    • Nested sampling algorithm for lattice field theories

  • Supervision of PhD students

  • Invited speaker at 2025 Scale Setting Workshop (ECT*)

  • Leading organizer of Hamiltonian lattice gauge theories workshop (ECT*)

  • Leading organizer of the Swiss Lattice Meeting, the first national meeting for lattice gauge theory in Switzerland (14-15 Jan. 2027)

  • Organization support for SIGN25 workshop at ITP Bern

Nov 2021 – Mar. 2024 · University of Bonn, Germany

Department:
Helmholtz Institute for Radiation and Nuclear Physics (HISKP)

Computational Physics group

Key Activities:

  • Ensemble production and analysis:

    • Contributed to generation and analysis of Extended Twisted Mass Collaboration (ETMC) gauge configurations
    • Code development for tmLQCD library

  • Hamiltonian formulations:

    • Quantum computing simulations of \(\mathrm{U}(1)\) gauge theories in 2+1 dimensions
    • Main developer and maintainer of specialized Monte Carlo library for Hamiltonian lattice gauge theories
    • Developed novel algorithms for \(\mathrm{SU}(2)\) gauge theories maximizing canonical commutation relations
    • Work on Hilbert space truncations via group manifold partitioning

  • Supervision of MS and PhD students

  • Teaching:

  • Organization support for the Lattice 2022 international conference

Nov 2018 – Oct 2021 · Roma Tre University, Rome, Italy

Department:
Department of Mathematics and Physics

Research Focus:

  • Leading Isospin Breaking Effects (LIBEs):
    • Calculated LIBEs on nucleon spectrum and \(\Delta(1232)\) resonances using RM123 method
    • Provided one of few lattice calculations of neutron-proton mass difference
    • Determined \(\Delta(1232)\) mass splittings
  • Methodological development:
    • Spectral decomposition of Euclidean lattice correlators
    • Advanced understanding of isospin symmetry breaking in QCD
  • Teaching:
    • Tutorial sessions for undergraduate courses

Outcomes:: Successfully defended Ph.D. thesis | Submission: 31st Oct. 2021 | Dissertation: 22 Apr. 2022

Awards and grants

  • 2025-2026: Person of Contact for a computing-time allocation of \(22.90\times10^{6}\) core-hours on the JUPITER Booster module, awarded by the Gauss Centre for Supercomputing (GCS).

  • 2025-2026: Principal Investigator (PI) of a computing-time allocation of \(0.20\times10^{6}\) core-hours on ALPS at CSCS, corresponding to \(0.80\times10^{6}\) GPU node-hours, for the continuum-limit calculation of the \(\eta,\eta'\) transition form factors on the ETM ensembles.

  • 2026-2029: Deputy Principal Investigator of a CSCS computing-time allocation (45 k node-hours per quarter, from October 2026 to September 2029) for the calculation of the hadronic light-by-light (HLbL) contribution to the anomalous magnetic moment of the muon.

  • 2026: Winner of a CHF 5000 + CHF 1500 grant from the Albert Einstein Center (AEC) for the organisation of the Swiss Lattice Meeting, the first national gathering for lattice gauge theory in Switzerland (14-15 Jan. 2027).

  • 2026: Winner of a CHF 3000 grant from the Open Round 2026 programme of the University of Bern, for a visiting research period at TU Wien, Vienna, Austria, from 15/05/2026 to 15/06/2026.

  • 2013-2016: Winner of a EUR 3000 merit scholarship awarded by Roma Tre University for academic excellence during the Bachelor’s degree.