Minimal equation
Minimal equation
Simplified equation
$y^2 + y = x^5 - 4x^3 - 7x^2 - 4x - 1$ | (homogenize, simplify) |
$y^2 + z^3y = x^5z - 4x^3z^3 - 7x^2z^4 - 4xz^5 - z^6$ | (dehomogenize, simplify) |
$y^2 = 4x^5 - 16x^3 - 28x^2 - 16x - 3$ | (homogenize, minimize) |
sage: R.<x> = PolynomialRing(QQ); C = HyperellipticCurve(R([-1, -4, -7, -4, 0, 1]), R([1]));
magma: R<x> := PolynomialRing(Rationals()); C := HyperellipticCurve(R![-1, -4, -7, -4, 0, 1], R![1]);
sage: X = HyperellipticCurve(R([-3, -16, -28, -16, 0, 4]))
magma: X,pi:= SimplifiedModel(C);
Invariants
Conductor: | \( N \) | \(=\) | \(3381\) | \(=\) | \( 3 \cdot 7^{2} \cdot 23 \) | magma: Conductor(LSeries(C)); Factorization($1);
|
Discriminant: | \( \Delta \) | \(=\) | \(165669\) | \(=\) | \( 3 \cdot 7^{4} \cdot 23 \) | magma: Discriminant(C); Factorization(Integers()!$1);
|
Igusa-Clebsch invariants
Igusa invariants
G2 invariants
\( I_2 \) | \(=\) | \(256\) | \(=\) | \( 2^{8} \) |
\( I_4 \) | \(=\) | \(5488\) | \(=\) | \( 2^{4} \cdot 7^{3} \) |
\( I_6 \) | \(=\) | \(635040\) | \(=\) | \( 2^{5} \cdot 3^{4} \cdot 5 \cdot 7^{2} \) |
\( I_{10} \) | \(=\) | \(-662676\) | \(=\) | \( - 2^{2} \cdot 3 \cdot 7^{4} \cdot 23 \) |
\( J_2 \) | \(=\) | \(128\) | \(=\) | \( 2^{7} \) |
\( J_4 \) | \(=\) | \(-232\) | \(=\) | \( - 2^{3} \cdot 29 \) |
\( J_6 \) | \(=\) | \(-33184\) | \(=\) | \( - 2^{5} \cdot 17 \cdot 61 \) |
\( J_8 \) | \(=\) | \(-1075344\) | \(=\) | \( - 2^{4} \cdot 3 \cdot 43 \cdot 521 \) |
\( J_{10} \) | \(=\) | \(-165669\) | \(=\) | \( - 3 \cdot 7^{4} \cdot 23 \) |
\( g_1 \) | \(=\) | \(-34359738368/165669\) | ||
\( g_2 \) | \(=\) | \(486539264/165669\) | ||
\( g_3 \) | \(=\) | \(543686656/165669\) |
sage: C.igusa_clebsch_invariants(); [factor(a) for a in _]
magma: IgusaClebschInvariants(C); IgusaInvariants(C); G2Invariants(C);
Automorphism group
\(\mathrm{Aut}(X)\) | \(\simeq\) | $C_2$ | magma: AutomorphismGroup(C); IdentifyGroup($1);
|
\(\mathrm{Aut}(X_{\overline{\Q}})\) | \(\simeq\) | $C_2$ | magma: AutomorphismGroup(ChangeRing(C,AlgebraicClosure(Rationals()))); IdentifyGroup($1);
|
Rational points
All points: \((1 : 0 : 0)\)
magma: [C![1,0,0]]; // minimal model
magma: [C![1,0,0]]; // simplified model
Number of rational Weierstrass points: \(1\)
magma: #Roots(HyperellipticPolynomials(SimplifiedModel(C)));
This curve is locally solvable everywhere.
magma: f,h:=HyperellipticPolynomials(C); g:=4*f+h^2; HasPointsEverywhereLocally(g,2) and (#Roots(ChangeRing(g,RealField())) gt 0 or LeadingCoefficient(g) gt 0);
Mordell-Weil group of the Jacobian
Group structure: \(\Z/{3}\Z\)
magma: MordellWeilGroupGenus2(Jacobian(C));
Generator | $D_0$ | Height | Order | |||||
---|---|---|---|---|---|---|---|---|
\(D_0 - 2 \cdot(1 : 0 : 0)\) | \(x^2 + xz + z^2\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(xz^2 + z^3\) | \(0\) | \(3\) |
Generator | $D_0$ | Height | Order | |||||
---|---|---|---|---|---|---|---|---|
\(D_0 - 2 \cdot(1 : 0 : 0)\) | \(x^2 + xz + z^2\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(xz^2 + z^3\) | \(0\) | \(3\) |
Generator | $D_0$ | Height | Order | |||||
---|---|---|---|---|---|---|---|---|
\(D_0 - 2 \cdot(1 : 0 : 0)\) | \(x^2 + xz + z^2\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(2xz^2 + 3z^3\) | \(0\) | \(3\) |
BSD invariants
Hasse-Weil conjecture: | unverified |
Analytic rank: | \(0\) |
Mordell-Weil rank: | \(0\) |
2-Selmer rank: | \(0\) |
Regulator: | \( 1 \) |
Real period: | \( 3.198951 \) |
Tamagawa product: | \( 3 \) |
Torsion order: | \( 3 \) |
Leading coefficient: | \( 1.066317 \) |
Analytic order of Ш: | \( 1 \) (rounded) |
Order of Ш: | square |
Local invariants
Prime | ord(\(N\)) | ord(\(\Delta\)) | Tamagawa | L-factor | Cluster picture |
---|---|---|---|---|---|
\(3\) | \(1\) | \(1\) | \(1\) | \(( 1 - T )( 1 + 2 T + 3 T^{2} )\) | |
\(7\) | \(2\) | \(4\) | \(3\) | \(1 + 4 T + 7 T^{2}\) | |
\(23\) | \(1\) | \(1\) | \(1\) | \(( 1 - T )( 1 - 3 T + 23 T^{2} )\) |
Galois representations
The mod-$\ell$ Galois representation has maximal image \(\GSp(4,\F_\ell)\) for all primes \( \ell \) except those listed.
Prime \(\ell\) | mod-\(\ell\) image | Is torsion prime? |
---|---|---|
\(2\) | 2.6.1 | no |
\(3\) | 3.80.1 | yes |
Sato-Tate group
\(\mathrm{ST}\) | \(\simeq\) | $\mathrm{USp}(4)$ |
\(\mathrm{ST}^0\) | \(\simeq\) | \(\mathrm{USp}(4)\) |
Decomposition of the Jacobian
Simple over \(\overline{\Q}\)
magma: HeuristicDecompositionFactors(C);
Endomorphisms of the Jacobian
Not of \(\GL_2\)-type over \(\Q\)
Endomorphism ring over \(\Q\):
\(\End (J_{})\) | \(\simeq\) | \(\Z\) |
\(\End (J_{}) \otimes \Q \) | \(\simeq\) | \(\Q\) |
\(\End (J_{}) \otimes \R\) | \(\simeq\) | \(\R\) |
All \(\overline{\Q}\)-endomorphisms of the Jacobian are defined over \(\Q\).
magma: //Please install CHIMP (https://github.com/edgarcosta/CHIMP) if you want to run this code
magma: HeuristicIsGL2(C); HeuristicEndomorphismDescription(C); HeuristicEndomorphismFieldOfDefinition(C);
magma: HeuristicIsGL2(C : Geometric := true); HeuristicEndomorphismDescription(C : Geometric := true); HeuristicEndomorphismLatticeDescription(C);