Gorenstein Algebras and Uniqueness of Additive ActionsWe study induced additive actions on projective hypersurfaces, i.e. regular
actions of the algebraic group $\mathbb G_a^m$ with an open orbit that can be
extended to a regular action on the ambient projective space. We prove that if
a projective hypersurface admits an induced additive action, then it is unique
if and only if the hypersurface is non-degenerate. We also show that for any
$n\geq 2$, there exists a non-degenerate hypersurface in $\mathbb P^n$ of each
degree $d$ from $2$ to $n$.
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