Is there a $2$ - dimensional submanifold $S$ of $\mathbb{R}^3$ which can be parametrized with $x : U \subset \mathbb{R}^2 \to S$ such that :
$E=G=1$, $F=0$, $e=-g=1$ and $f=0$
Where $E,F,G$ and $e,f,g$ are the coefficients of the first and second fundamental form.
I think that such a submanifold exists. Indeed since the coefficients does not contradict the fact that the first fundamental form is symmetric non negative and the second fundamental form is symmetric I think such a submanifold exists.
But I am not able to prove it. I don't even know where to start!
Thanks in advance.
Such a surfaces does not exist. Note that besides the symmetry of first, second fundamental form, they also need to satisfy the Gauss equation
$$2K = \det(I^{-1} II),$$
where $I, II$ are the first and second fundamental form respectively. However, from the first fundamental form we have $K = 0$, while $\det (g^{-1} A) = 1 \neq 0$. Thus such a surface does not exist.