Function dec_max_speed 

pub fn dec_max_speed<const D: usize, R: DecNsScalar>(
    manifold: &Manifold<LatticeComplex<D, R>, R>,
    edge_form: &CausalTensor<R>,
) -> Result<R, PhysicsError>

Maximum pointwise speed: sharp recovers vertex vectors (layout vertex * D + axis), the maximum Euclidean norm is returned.

Errors

PhysicsError::TopologyError wrapping a sharp failure (wrong edge count or missing metric).