Julien Portier

Julien Portier is a mathematician and postdoctoral researcher at EPFL in the Chair of Extremal Combinatorics (Oliver Janzer's group), working on graph theory, extremal and probabilistic combinatorics. He completed a PhD in Pure Mathematics at the University of Cambridge (2021-2025) under Bela Bollobas, after an MS in Combinatorics/Probability at Cambridge (2020-2021) and a master's in mathematics at Ecole Polytechnique (2017-2020). As a high-school student at Lycee Louis-le-Grand he represented France at the International Mathematical Olympiad in 2014 and 2015, winning a bronze medal in each. His public LinkedIn also records a 2020 Quantitative Researcher role at Millennium in Geneva.

Notes1

• Quant employment verification: CONFIRMED. The person's own LinkedIn profile (ch.linkedin.com/in/julien-portier-316b01177) lists 'Quantitative Researcher, Millennium, mars 2020 - août 2020 (6 mois), Geneve', an actual past role with start/end months, and the identity is corroborated across independent sources (EPFL people page, personal site, IMO results, Cambridge thesis) all naming the same Julien Pierre Daniel Portier. The employer, Millennium Management (mlp.com), is a multi-strategy alternative investment firm whose own site describes 'Quantitative Strategies' teams doing systematically-driven investing - it genuinely operates in quantitative finance, not merely a name containing 'quant'. Caveat: the role is index/LinkedIn-sourced with a 6-month (internship-length) window and no separate primary employer document was located; no other quant employer lead surfaced.Aug 2020
• No certification is indicated by any source checked (EPFL, personal site, LinkedIn, IMO); the person's credentials are academic degrees rather than professional certifications.2026