Kalai's conjecture (Frankl and Füredi 1987) states that, for ,
, and every tight tree
with
hyperedges,
where
is the maximum number of hyperedges
in an
-vertex
-uniform
hypergraph containing no copy of
. When
, the statement is the Erdős-Sós conjecture.
Mubayi and Verstraëte (2026) proved the stronger hypergraph shadow bound
The bound is attained for infinitely many . The authors report that GPT-6 Astra found the proof and that
they checked and rewrote it. Independent external review had not been reported as
of Sep. 23, 2026.