Let G be a cancellative 3-uniform hypergraph in which the symmetric difference of any two edges is not contained in a third one. Equivalently, a 3-uniform hypergraph G is cancellative if and only if G is {F4,F5}
Nearby in the stack
-free, where
F4={abc,abd,bcd}
and
F5={abc,abd,cde}
. A classical result in extremal combinatorics stated that the maximum size of a cancellative hypergraph is achieved by the balanced complete tripartite
3
-uniform hypergraph, which was firstly proved by Bollobás and later by Keevash and Mubayi. In this paper, we consider spectral extremal problems for cancellative hypergraphs. More precisely, we determine the maximum
p
-spectral radius of cancellative
3
-uniform hypergraphs, and characterize the extremal hypergraph. As a by-product, we give an alternative proof of Bollobás' result from spectral viewpoint.