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« An Exotic Growth Rate in Ramsey Theory

An Exotic Growth Rate in Ramsey Theory

April 29, 2024, 2:00 PM - 3:00 PM

Location:

Conference Room 705

Rutgers University

Hill Center

110 Frelinghuysen Rd

Piscataway, NJ 08854

Xiaoyu He, Princeton University

The vast majority of natural Ramsey numbers studied to date have polynomial or exponential growth rates. We give a hypergraph Ramsey number - perhaps the simplest of its kind - with an unusual intermediate growth rate. Namely, let S_n be the 3-uniform star (with n+1 vertices and (n choose 2) edges) and let K_4 be the complete 3-uniform hypergraph on 4 vertices. We show  2^{c(log n)^2} < r(K_4, S_n) < 2^{n^{2/3+o(1)}}.

Based on joint work with David Conlon, Jacob Fox, Dhruv Mubayi, Andrew Suk, and Jacques Verstraete.