The University College London (UCL) Combinatorics Seminar is held every Monday at 4–5pm during term time.

The venue for seminars this term is Room 346 at the SSEES Bulding, 14–16 Taviton Street.

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Next Speaker

• 23rd February 2026 - Jeck Lim (University of Oxford)

  On exponential Freiman dimension

  
  

  The exponential Freiman dimension of a finite set $A \subseteq \mathbf{R}^{m}$, introduced by Green and Tao in 2006, represents the largest positive integer $d$ for which $A$ contains the vertices of a non-degenerate $d$-dimensional parallelepiped. For every $d \geqslant 1$, we precisely determine the largest constant $C_{d}>0$ (exponential in $d$) for which $|A+A| \geqslant C_{d}|A| - O_{d}(1)$ holds for all sets $A$ with exponential Freiman dimension $d$.

  Joint work with Akshat Mudgal, Cosmin Pohoata and Xuancheng Shao.