We revisit the Allendoerfer–Weil formula for the Euler characteristic of embedded hypersurfaces in
constant sectional curvature manifolds, taking time to re-prove it while demonstrating techniques of
(Albuquerque 2019a) and then applying it to gain new understanding of isoparametric hypersurfaces.
Keywords
Euler characteristic, hypersurface, mean curvatures, space
form, isoparametric hypersurface