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edgarcosta / endomorphisms

Rigorous computation of the endomorphism ring of a Jacobian
GNU General Public License v2.0
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Bug in Period Matrix for a CM picard curve #61

Open edgarcosta opened 1 year ago

edgarcosta commented 1 year ago 
> P2<x,y,z> := ProjectiveSpace(RationalsExtra(500), 2);
> C := Curve(P2, x^4 - 6048*x^2*z^2 + 235008*x*z^3 - 2301696*z^4 - z*y^3);
> time #GeometricEndomorphismRepresentationCC(PeriodMatrix(C));
2
Time: 14.780
> R<T> := PolynomialRing(ComplexFieldExtra(200));
> S := RiemannSurface(T^4 - 6048*T^2 + 235008*T - 2301696, 3);
> PS := Matrix(BaseRing(R), HorizontalJoin(Submatrix(P, 1,g+1, g,g), Submatrix(P, 1,1,   g,g))) where P:= S`BigPeriodMatrix where g := 3;
> #GeometricEndomorphismRepresentationCC(PS);
6