Minimal equation
Minimal equation
Simplified equation
| $y^2 = x^5 - x^4 - 4x^3 + 3x^2 + 4x - 2$ | (homogenize, simplify) |
| $y^2 = x^5z - x^4z^2 - 4x^3z^3 + 3x^2z^4 + 4xz^5 - 2z^6$ | (dehomogenize, simplify) |
| $y^2 = x^5 - x^4 - 4x^3 + 3x^2 + 4x - 2$ | (homogenize, minimize) |
sage: R.<x> = PolynomialRing(QQ); C = HyperellipticCurve(R([-2, 4, 3, -4, -1, 1]), R([]));
magma: R<x> := PolynomialRing(Rationals()); C := HyperellipticCurve(R![-2, 4, 3, -4, -1, 1], R![]);
sage: X = HyperellipticCurve(R([-2, 4, 3, -4, -1, 1]))
magma: X,pi:= SimplifiedModel(C);
Invariants
| Conductor: | \( N \) | \(=\) | \(100352\) | \(=\) | \( 2^{11} \cdot 7^{2} \) | magma: Conductor(LSeries(C)); Factorization($1);
|
| Discriminant: | \( \Delta \) | \(=\) | \(100352\) | \(=\) | \( 2^{11} \cdot 7^{2} \) | magma: Discriminant(C); Factorization(Integers()!$1);
|
Igusa-Clebsch invariants
Igusa invariants
G2 invariants
| \( I_2 \) | \(=\) | \(304\) | \(=\) | \( 2^{4} \cdot 19 \) |
| \( I_4 \) | \(=\) | \(1372\) | \(=\) | \( 2^{2} \cdot 7^{3} \) |
| \( I_6 \) | \(=\) | \(149940\) | \(=\) | \( 2^{2} \cdot 3^{2} \cdot 5 \cdot 7^{2} \cdot 17 \) |
| \( I_{10} \) | \(=\) | \(392\) | \(=\) | \( 2^{3} \cdot 7^{2} \) |
| \( J_2 \) | \(=\) | \(608\) | \(=\) | \( 2^{5} \cdot 19 \) |
| \( J_4 \) | \(=\) | \(11744\) | \(=\) | \( 2^{5} \cdot 367 \) |
| \( J_6 \) | \(=\) | \(71936\) | \(=\) | \( 2^{8} \cdot 281 \) |
| \( J_8 \) | \(=\) | \(-23546112\) | \(=\) | \( - 2^{8} \cdot 3 \cdot 23 \cdot 31 \cdot 43 \) |
| \( J_{10} \) | \(=\) | \(100352\) | \(=\) | \( 2^{11} \cdot 7^{2} \) |
| \( g_1 \) | \(=\) | \(40568406016/49\) | ||
| \( g_2 \) | \(=\) | \(1288833536/49\) | ||
| \( g_3 \) | \(=\) | \(12984448/49\) |
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: \((1 : 0 : 0),\, (1 : -1 : 1),\, (1 : 1 : 1)\)
magma: [C![1,-1,1],C![1,0,0],C![1,1,1]]; // minimal model
magma: [C![1,-1/2,1],C![1,0,0],C![1,1/2,1]]; // 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: \(\Z \oplus \Z/{2}\Z\)
magma: MordellWeilGroupGenus2(Jacobian(C));
| Generator | $D_0$ | Height | Order | |||||
|---|---|---|---|---|---|---|---|---|
| \((1 : -1 : 1) - (1 : 0 : 0)\) | \(x - z\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(-z^3\) | \(0.695932\) | \(\infty\) |
| \(D_0 - 2 \cdot(1 : 0 : 0)\) | \(x^2 - 2z^2\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(0\) | \(0\) | \(2\) |
| Generator | $D_0$ | Height | Order | |||||
|---|---|---|---|---|---|---|---|---|
| \((1 : -1 : 1) - (1 : 0 : 0)\) | \(x - z\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(-z^3\) | \(0.695932\) | \(\infty\) |
| \(D_0 - 2 \cdot(1 : 0 : 0)\) | \(x^2 - 2z^2\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(0\) | \(0\) | \(2\) |
| Generator | $D_0$ | Height | Order | |||||
|---|---|---|---|---|---|---|---|---|
| \((1 : -1/2 : 1) - (1 : 0 : 0)\) | \(x - z\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(-1/2z^3\) | \(0.695932\) | \(\infty\) |
| \(D_0 - 2 \cdot(1 : 0 : 0)\) | \(x^2 - 2z^2\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(0\) | \(0\) | \(2\) |
2-torsion field: 6.6.1229312.1
BSD invariants
| Hasse-Weil conjecture: | unverified |
| Analytic rank: | \(1\) |
| Mordell-Weil rank: | \(1\) |
| 2-Selmer rank: | \(2\) |
| Regulator: | \( 0.695932 \) |
| Real period: | \( 11.58932 \) |
| Tamagawa product: | \( 1 \) |
| Torsion order: | \( 2 \) |
| Leading coefficient: | \( 2.016345 \) |
| Analytic order of Ш: | \( 1 \) (rounded) |
| Order of Ш: | square |
Local invariants
| Prime | ord(\(N\)) | ord(\(\Delta\)) | Tamagawa | L-factor | Cluster picture |
|---|---|---|---|---|---|
| \(2\) | \(11\) | \(11\) | \(1\) | \(1\) | |
| \(7\) | \(2\) | \(2\) | \(1\) | \(1 + 7 T^{2}\) |  |
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? |
|---|---|---|
| \(2\) | 2.120.5 | 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);