Totally quasi-umbilic timelike surfaces in $\mathbb{R}^{1,2}$
Totally quasi-umbilic timelike surfaces in $\mathbb{R}^{1,2}$
For a regular surface in Euclidean space R 3 , umbilic points are precisely the points where the Gauss and mean curvatures K and H satisfy H 2 = K; moreover, it is well-known that the only totally umbilic surfaces in R 3 are planes and spheres.But for timelike surfaces …