2 problems

Let $k$ be a field of characteristic different from $2$, and let $u(k)$ denote the maximal dimension of an anisotropic quadratic form over $k$. Kaplansky's conjecture. If…

Let $F$ be a field of characteristic different from $2$, and let $n\geq 2$. Say that $F$ has property $PN(n)$ if every quadratic form over $F$ of dimension $2^n+1$ is a Pfister nei…