About Me

I am a PhD candidate in Quantum Machine Learning at the University of Basel, working at the intersection of mathematical physics, theoretical computer science, and statistical learning theory. My research focuses on the interplay between trainability, computational complexity, and generalization: when quantum models can be trained efficiently, what makes them hard to simulate classically, and how their architectures determine statistical performance.

I approach these questions using high-dimensional probability, random matrix theory, optimization, and computational complexity theory.

I am part of the Optimization of Machine Learning Systems Group. My research is supported by the Swiss National Science Foundation and conducted in collaboration with IBM Research Zürich.

My interest in computation began with a curiosity about how software can simulate physical worlds. Outside research, I produce music across different genres and styles; some of it is available on YouTube.

Research Highlights

Trainability beyond easy classical simulation?

Our work introduces the Taylor surrogate and Linear Clifford Encoder to study gradient scaling and simulation complexity near Clifford circuits. We obtain rigorous guarantees in specified regimes and numerical evidence of a possible transition that calls for further theoretical investigation.

Designing quantum models that generalize beyond interpolation

We characterize double descent with correlated features and translate the theory to quantum extreme learning machines. Encoding strength, input reuploads, and measurement shots provide ways to reshape feature covariance and stabilize learning near interpolation.

Research

Three closely connected questions guide my work: how quantum models can be trained, when their behavior can be reproduced classically, and how reliably they generalize from data.

Optimization Landscapes and Trainability When can quantum models avoid vanishing gradients? Barren plateaus can cause gradients to vanish exponentially with system size. We introduced the Linear Clifford Encoder, which ensures constant-scaling gradients in specified landscape regions close to Clifford circuits. This gives us a concrete framework for studying favorable optimization landscapes and their limitations.
Classical Simulation and Computational Complexity Can favorable trainability persist outside efficiently simulable regimes? We developed the Taylor surrogate for classical simulation near Clifford circuits and analyzed how computational complexity changes beyond known efficient-simulation regimes. Numerical results suggest an intriguing transition in gradient behavior, but establishing a general coexistence of trainability and classical hardness remains an open question.
Generalization and Double Descent How do feature correlations and quantum circuit design shape prediction risk? We analytically characterize the double-descent risk curve in correlated linear regression using covariance conditioning and spectral correlation strength. Applied to quantum extreme learning machines, the theory shows how encoding, input reuploading, and finite measurement shots can regularize feature covariance and stabilize the interpolation threshold.

Publications

  1. Sabri Meyer, Francesco Scala, Francesco Tacchino, and Aurélien Lucchi. Gradient scalability and Taylor surrogation of quantum cost landscapes. Phys. Rev. Research 8, 023325, 2026.

    Introduces a Taylor surrogate for classical simulation near Clifford circuits and a Linear Clifford Encoder for controlling gradient scaling. The work establishes rigorous guarantees in specific regimes and presents preliminary numerical evidence of a possible trainability–complexity transition.

Preprints

  1. Sabri Meyer, Ege Yilmaz, Aurélien Lucchi, Francesco Tacchino, and Francesco Scala. Shaping double descent in quantum extreme learning through model design. arXiv preprint arXiv:2610.06581, 2026.

    Analytically characterizes the full double-descent risk curve for correlated linear features and applies the theory to quantum extreme learning machines. Shows how encoding strength, input reuploads, and finite measurement shots regularize the output covariance and can stabilize the interpolation threshold.

Selected Conferences & Research Schools

Selected conferences, workshops, and research schools attended.

LHC Quantum Computing Workshop 2026 — Quantum Computing in High-Energy Physics
University of Valencia, Spain
QIP 2026 — 29th Annual Quantum Information Processing Conference
ATTA Centre, Riga, Latvia
QTML 2025 — 9th International Conference on Quantum Techniques in Machine Learning
Marina Bay Sands, Singapore
LMS Research School 2025 — Quantum Machine Learning and Hamiltonian Simulation
Sabhal Mòr Ostaig, Scotland
QTML 2024 — 8th International Conference on Quantum Techniques in Machine Learning
University of Melbourne, Australia

Teaching

Teaching Assistant, Mathematics of Data Science — University of Basel (Fall 2023 – Present).

Topics include probability and mathematical statistics, random matrix theory, high-dimensional analysis, neural networks, and graph-based learning methods such as spectral clustering and diffusion maps.

Education

2023 – Present
PhD Candidate in Quantum Machine Learning
University of Basel
  • Electives in Algebraic Geometry
2021 – 2023
Master of Science in Mathematics
University of Basel
  • Specialized in Algebraic Number Theory, Analysis of PDEs, and Stochastic Analysis
  • Master Thesis on the Hessian Eigenspectrum of Nonlinear Neural Networks
  • Electives in Theoretical Quantum Mechanics
2018 – 2021
Bachelor of Science in Mathematics
University of Basel
  • Electives in Physics & Computer Science