Let $(\mathcal C,\otimes,\mathbb 1)$ be an abelian symmetric monoidal category satisfying certain exactness conditions. In this paper we define a presheaf $\mathbb P^{n}_{\mathcal C}$ on the category of commutative algebras in $\mathcal C$ and we prove that this functor is a $\mathcal C$-scheme in the sense of Toen and Vaqui��. This construction gives us a context of non-associative relative algebraic geometry. The most important example of the construction is the octonionic projective space.

23 pages