3 problems

Assume that $\mathbb{P}^2_k$ is obtained from $\mathbb{P}^2$ by blowing up $k$ generic real points and is equipped with its natural real structure. Let $D\subset \mathbb{P}^2_k$ be…

Let $(\mathbb{R}P^1)^3$ be the product of three real projective lines with the standard real structure, and let $\mathfrak{s}_{(\mathbb{R}P^1)^3}$ be the $Spin_3$-structure over…

Let $d$ be a positive integer, and let $W_{\mathbb{R}P^3}(d,l)$ denote the Welschinger invariant of degree $d$ with the parameter $l$ specifying the real-point constraint. Equality…