3 problems

Let $X\to \mathbb{A}^m$ be an $\mathbb{A}^n$-fibration, meaning that every fibre is isomorphic to $\mathbb{A}^n$. Dolgachev-Weisfeiler conjecture. The fibration is isomorphic to th…

Let $mF$ be a multiple fiber of a smooth $\mathbb A^1$-fiber space with irreducible fibers. Let $k$ be the coefficient of $F$ in the canonical divisor $K_X$. Define a rational numb…

A $(p,n)$-fibration is a fibration of Euclidean space by affine copies of $\mathbb R^p$, with $q=n-p$. A copy of $\mathbb R^q$ is transverse to every fiber when it is transverse to…