Fanography

A tool to visually study the geography of Fano 3-folds.

Identification

Fano variety 1-8

section of Plücker embedding of $\mathrm{SGr}(3,6)$ by codimension 3 subspace

Picard rank
1 (others)
$-\mathrm{K}_X^3$
16
$\mathrm{h}^{1,2}(X)$
3
Hodge diamond and polyvector parallelogram
1
0 0
0 1 0
0 3 3 0
0 1 0
0 0
1
1
0 0
0 12 0
0 0 0 11
0 0 0
0 0
0
Anticanonical bundle
index
1
$\dim\mathrm{H}^0(X,\omega_X^\vee)$
11
$-\mathrm{K}_X$ very ample?
yes
$-\mathrm{K}_X$ basepoint free?
yes
hyperelliptic
no
trigonal
no
Birational geometry

This variety is rational.


This variety is primitive.


This variety is fibre-like, i.e. it can appear as the fibre of a Mori fibre space.

Deformation theory
number of moduli
12
Bott vanishing
does not hold
$\mathrm{Aut}^0(X)$ $\dim\mathrm{Aut}^0(X)$ number of moduli
$0$ 0 12
Period sequence

The following period sequences are associated to this Fano 3-fold:

GRDB
#143
Fanosearch
#20
Semiorthogonal decompositions

There exist interesting semiorthogonal decompositions, but this data is not yet added.

Structure of quantum cohomology

By Hertling–Manin–Teleman we have that quantum cohomology cannot be generically semisimple, as $\mathrm{h}^{1,2}\neq 0$.

Zero section description

Fano 3-folds from homogeneous vector bundles over Grassmannians gives the following description(s):

variety
$\operatorname{Gr}(3,6)$
bundle
$\bigwedge^2\mathcal{U}^{\vee} \oplus \mathcal{O}(1)^{\oplus3}$

See the big table for more information.

K-stability
  • every member is K‑stable
  • every member is K‑polystable
  • every member is K‑semistable
See and the big table for more information.
Hilbert schemes of curves

The Hilbert scheme of conics is the ruled surface obtained from projectivisation of simple rank 2 bundle over a smooth curve of genus 3.

Its Hodge diamond is

1
3 3
0 2 0
3 3
1