Extremal Graph Theory and Ramsey Theory (PCMI 2025 Undergraduate Summer School)
by Yuval Wigderson (notes by Sanjana Das) · Institute for Advanced Study / PCMI
The only genuinely accessible on-ramp found that is still fully rigorous: it assumes no graduate background, builds extremal numbers from Mantel forward, and proves Erdős-Stone-Simonovits and Kővári-Sós-Turán in full. Eighty pages of notes from Yuval Wigderson's 2025 PCMI undergraduate summer school, working from extremal numbers and Erdős-Stone-Simonovits through Kővári-Sós-Turán, supersaturation and stability, then continuing into graph and hypergraph Ramsey numbers.
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