Free Immersions in Critical Dimension from Lie Groups

Abstract

We construct free immersions of $P^3\times S^1$ and $S^3\times S^1$ into $14$-space. These are the first examples of free immersions in critical dimension of closed manifolds that are not spheres, projective spaces, tori, or surfaces. The idea is to mimic De Leo's construction for $m$-tori with $m\le 5$. De Leo constructs a map that is symmetric with respect to a representation of the Lie group formed by the $(m-1)$-torus; we replace this group with $\mathrm{SO}(3)$. In our examples, the osculating determinant is constant.

arXiv comment16 pages. Besides minor changes, updated to mention [DL26b]