There is a symbolic notation for the set of all eigenvalues $$\operatorname{spec} \varphi = \lbrace \lambda \in K \mid \lambda \textrm{ is an eigenvalue} \rbrace$$ There is also a notation for the eigenspace $$V_\lambda = \lbrace \alpha \in V \mid \varphi(\alpha) = \lambda \alpha \rbrace$$ Is there any standard notation for the set of all eigenvectors? So that instead of writing
Let $v$ be an eigenvector
we could write
Let $v \in \dots$
Not sure this is an answer, too long for a comment.
I'd be surprised if there were a standard notation for the set of eigenvectors, since that set doesn't have nice geometry. (Think about it for the eigenvectors of the matrix with 1, 2, 2, on the diagonal.)
Arguments about eigenvectors usually begin