Try fix norm by using metric.square_root_of_expr instead of sqrt

galgebra/mv.py

@@ -1312,7 +1312,7 @@ def norm(self, hint='0') -> Expr:
           sign, except when the quadratic form's sign can be determined
           by other considerations, such as the metric being Euclidean.
         """
-        return simplify(sqrt(self.norm2(hint)))
+        return simplify(metric.square_root_of_expr(self.norm2(hint)))
     # ## GSG code ends ###
 
     __abs__ = norm  # allow `abs(x)` to call z.norm()