About Me

Ahoy there! My name is Stefan Grosser, and I am a final year PhD student in Computer Science at McGill University studying under Robert Robere. My research interests are in proof complexity, bounded arithmetic, communication complexity, and extremal combinatorics. I will be joining Rahul Santhanam's meta-complexity group at Oxford in September 2026 as a postdoc. 

From January through May 2023, I was a visiting graduate student at the Simons Institute for the Meta-Complexity program. For the summer of 2025, I was a research intern on the IBM Exploratory Science team. In Fall 2026, I will be a visiting researcher at the Isaac Newton Institute of University of Cambridge for their Logical Foundations of Complexity semester program.

I had the privilege of working with Hamed Hatami and Sergey Norin for my Master's in Mathematics at McGill, and Alejandro Morales during my final year at UMass Amherst.

If I'm not doing math or programming, you'll find me climbing, baking, playing my oud, or drinking a cup of tea.

Find my CV here

Papers: 

• Provable Reductions in TFNP
       - Joint work with Noah Fleming, Toni Pitassi, and Robert Robere
       - Submitted

• Limits of Lifting
       - Joint work with Gaia Garenini, Bruno P. Cavalar, and Jan Pich
       - Submitted

• Total Search Problems in ZPP
       - Joint work with Noah Fleming, Weiqiang Yuan, Hanlin Ren, Morgan Shirley, Jiawei Li, and Siddhartha Jain
       - Accepted to ITCS 2026

       - arXiv link

• Student-Teacher Constructive Separations and (Un)Provability in Bounded Arithmetic: Witnessing the Gap
       - Joint work with Marco Carmosino
       - Accepted to STOC 2025
       - ECCC link
       - STOC prerecorded talk

• Black-Box PPP is Not Turing Closed
       - Joint work with Noah Fleming, Toni Pitassi, and Robert Robere
       - Accepted to STOC 2024

       - ECCC link

       - STOC prerecorded talk

       - Speaker at GSCC 2024

• On Semi-algebraic Proofs and Algorithms
       - Joint work with Noah Fleming, Mika Göös, and Robert Robere
       - Accepted to ITCS 2022

       - ECCC link
       - ITCS Talk

• Typical structure of hereditary properties of binary matroids
       - [Accepted to Journal of Combinatorial Theory Series B] Joint work with Sergey Norin and Hamed Hatami, and Peter Nelson
       - arxiv link

• Counting Linear Extensions of Posets with Determinants of Hook Lengths
       - [Accepted to SIDMA] Joint work with Alexander Garver, Jacob Matherne, and Alejandro Morales
       - arXiv link, SIAM link 
       - JMM 2019 poster. Won the MAA Outstanding Poster Award
       - Poster at FPSAC 2022

Projects:

• Google Summer of Code 2020: Adding Efficient Counting of Linear Extensions to SageMath
         - Mentored by Travis Scrimshaw

• ENNUI - Elegant Neural Network User Interface (Released open source)
         - Developed with Jesse Michel and Zack Holbrook
         - Mentored by Gilbert Strang and Hendrik Strobelt
         - Used in MIT courses 18.06 and 18.065

Github

Contact me at myfirstname.mylastname @ mail.mcgill.ca