- Source: Beauville surface
In mathematics, a Beauville surface is one of the surfaces of general type introduced by Arnaud Beauville (1996, exercise X.13 (4)). They are examples of "fake quadrics", with the same Betti numbers as quadric surfaces.
Construction
Let C1 and C2 be smooth curves with genera g1 and g2.
Let G be a finite group acting on C1 and C2 such that
G has order (g1 − 1)(g2 − 1)
No nontrivial element of G has a fixed point on both C1 and C2
C1/G and C2/G are both rational.
Then the quotient (C1 × C2)/G is a Beauville surface.
One example is to take C1 and C2 both copies of the genus 6 quintic
X5 + Y5 + Z5 =0, and G to be an elementary abelian group of order 25, with suitable actions on the two curves.
Invariants
Hodge diamond:
References
Barth, Wolf P.; Hulek, Klaus; Peters, Chris A.M.; Van de Ven, Antonius (2004), Compact Complex Surfaces, Ergebnisse der Mathematik und ihrer Grenzgebiete. 3. Folge., vol. 4, Springer-Verlag, Berlin, ISBN 978-3-540-00832-3, MR 2030225
Beauville, Arnaud (1996), Complex algebraic surfaces, London Mathematical Society Student Texts, vol. 34 (2nd ed.), Cambridge University Press, ISBN 978-0-521-49510-3, MR 1406314