del Pezzo surface: $\mathrm{Bl}_3\mathbb{P}^2$
Identification
$\mathrm{Bl}_2\mathbb{P}^2$ $\mathrm{Bl}_4\mathbb{P}^2$
del Pezzo surface $\mathrm{Bl}_3\mathbb{P}^2$
- Picard rank
- 4
- $-\mathrm{K}_S^2$
- 6
- alternatives
-
divisor of degree $(1,1,1)$ in $\mathbb{P}^1\times\mathbb{P}^1\times\mathbb{P}^1$
complete intersection of two $(1,1)$-divisors in $\mathbb{P}^2\times\mathbb{P}^2$
Hodge diamond
1
0 0
0 4 0
0 0
1
0 0
0 4 0
0 0
1
Anticanonical bundle
- index
- 1
- $\dim\mathrm{H}^0(S,\omega_S^\vee)$
- 7
- $-\mathrm{K}_S$ very ample?
- yes
Deformation theory
- number of moduli
- 0
- Bott vanishing
- holds
Automorphism groups
group | dimension | |
$(\mathbb{G}_{\mathrm{m}}^2\rtimes\mathrm{Sym}_3)\times\mathrm{Sym}_2$ | 2 |