Dear Colleagues and Students,
You are cordially invited to the Algebra Seminar organized by the Department of Mathematics.
Title: Eigenvalues of characters, Adams operations, and Feit’s conjecture.
Speaker: Robert Boltje (University of California, Santa Cruz)
Abstract: We introduce an integer $S(G,\chi,n)$ associated to a finite group $G$, a character $\chi$ of $G$ and a positive divisor $n$ of the exponent of $G$. It can be defined in two different ways: As the sum of certain coefficients of the canonical induction formula of $\chi$, or as the multiplicity of the trivial character in an alternating sum of Adams operations of $\chi$. It turns out that this integer is always non-negative and that it is positive if and only if there exists an eigenvalue of order $n$ for one of the matrices appearing in a representation affording $\chi$. This is joint work with Gabriel Navarro and is motivated by the Feit Conjecture. No further knowledge than some character theory is necessary.
Date: 9 September 2026
Time: 15:30
Place: SA-141