Minimal equation
Minimal equation
Simplified equation
$y^2 + y = 2x^5 + 3x^4 + x^3$ | (homogenize, simplify) |
$y^2 + z^3y = 2x^5z + 3x^4z^2 + x^3z^3$ | (dehomogenize, simplify) |
$y^2 = 8x^5 + 12x^4 + 4x^3 + 1$ | (homogenize, minimize) |
sage: R.<x> = PolynomialRing(QQ); C = HyperellipticCurve(R([0, 0, 0, 1, 3, 2]), R([1]));
magma: R<x> := PolynomialRing(Rationals()); C := HyperellipticCurve(R![0, 0, 0, 1, 3, 2], R![1]);
sage: X = HyperellipticCurve(R([1, 0, 0, 4, 12, 8]))
magma: X,pi:= SimplifiedModel(C);
Invariants
Conductor: | \( N \) | \(=\) | \(24320\) | \(=\) | \( 2^{8} \cdot 5 \cdot 19 \) | magma: Conductor(LSeries(C)); Factorization($1);
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Discriminant: | \( \Delta \) | \(=\) | \(243200\) | \(=\) | \( 2^{9} \cdot 5^{2} \cdot 19 \) | magma: Discriminant(C); Factorization(Integers()!$1);
|
Igusa-Clebsch invariants
Igusa invariants
G2 invariants
\( I_2 \) | \(=\) | \(6\) | \(=\) | \( 2 \cdot 3 \) |
\( I_4 \) | \(=\) | \(54\) | \(=\) | \( 2 \cdot 3^{3} \) |
\( I_6 \) | \(=\) | \(-792\) | \(=\) | \( - 2^{3} \cdot 3^{2} \cdot 11 \) |
\( I_{10} \) | \(=\) | \(950\) | \(=\) | \( 2 \cdot 5^{2} \cdot 19 \) |
\( J_2 \) | \(=\) | \(12\) | \(=\) | \( 2^{2} \cdot 3 \) |
\( J_4 \) | \(=\) | \(-138\) | \(=\) | \( - 2 \cdot 3 \cdot 23 \) |
\( J_6 \) | \(=\) | \(6116\) | \(=\) | \( 2^{2} \cdot 11 \cdot 139 \) |
\( J_8 \) | \(=\) | \(13587\) | \(=\) | \( 3 \cdot 7 \cdot 647 \) |
\( J_{10} \) | \(=\) | \(243200\) | \(=\) | \( 2^{9} \cdot 5^{2} \cdot 19 \) |
\( g_1 \) | \(=\) | \(486/475\) | ||
\( g_2 \) | \(=\) | \(-1863/1900\) | ||
\( g_3 \) | \(=\) | \(13761/3800\) |
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);
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Rational points
Known points | |||||
---|---|---|---|---|---|
\((1 : 0 : 0)\) | \((0 : 0 : 1)\) | \((-1 : 0 : 1)\) | \((0 : -1 : 1)\) | \((-1 : -1 : 1)\) | \((-1 : 0 : 2)\) |
\((1 : 2 : 1)\) | \((1 : -3 : 1)\) | \((-1 : -8 : 2)\) | \((3 : 27 : 1)\) | \((3 : -28 : 1)\) | \((20 : 2624 : 1)\) |
\((20 : -2625 : 1)\) |
Known points | |||||
---|---|---|---|---|---|
\((1 : 0 : 0)\) | \((0 : 0 : 1)\) | \((-1 : 0 : 1)\) | \((0 : -1 : 1)\) | \((-1 : -1 : 1)\) | \((-1 : 0 : 2)\) |
\((1 : 2 : 1)\) | \((1 : -3 : 1)\) | \((-1 : -8 : 2)\) | \((3 : 27 : 1)\) | \((3 : -28 : 1)\) | \((20 : 2624 : 1)\) |
\((20 : -2625 : 1)\) |
Known points | |||||
---|---|---|---|---|---|
\((1 : 0 : 0)\) | \((0 : -1 : 1)\) | \((0 : 1 : 1)\) | \((-1 : -1 : 1)\) | \((-1 : 1 : 1)\) | \((1 : -5 : 1)\) |
\((1 : 5 : 1)\) | \((-1 : -8 : 2)\) | \((-1 : 8 : 2)\) | \((3 : -55 : 1)\) | \((3 : 55 : 1)\) | \((20 : -5249 : 1)\) |
\((20 : 5249 : 1)\) |
magma: [C![-1,-8,2],C![-1,-1,1],C![-1,0,1],C![-1,0,2],C![0,-1,1],C![0,0,1],C![1,-3,1],C![1,0,0],C![1,2,1],C![3,-28,1],C![3,27,1],C![20,-2625,1],C![20,2624,1]]; // minimal model
magma: [C![-1,-8,2],C![-1,-1,1],C![-1,1,1],C![-1,8,2],C![0,-1,1],C![0,1,1],C![1,-5,1],C![1,0,0],C![1,5,1],C![3,-55,1],C![3,55,1],C![20,-5249,1],C![20,5249,1]]; // 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: \(\Z \oplus \Z \oplus \Z/{2}\Z\)
magma: MordellWeilGroupGenus2(Jacobian(C));
Generator | $D_0$ | Height | Order | |||||
---|---|---|---|---|---|---|---|---|
\((-1 : -1 : 1) + (0 : -1 : 1) - 2 \cdot(1 : 0 : 0)\) | \(x (x + z)\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(-z^3\) | \(0.421492\) | \(\infty\) |
\((0 : -1 : 1) - (1 : 0 : 0)\) | \(x\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(-z^3\) | \(0.121889\) | \(\infty\) |
\(D_0 - 2 \cdot(1 : 0 : 0)\) | \(2x^2 + 2xz + z^2\) | \(=\) | \(0,\) | \(2y\) | \(=\) | \(-z^3\) | \(0\) | \(2\) |
Generator | $D_0$ | Height | Order | |||||
---|---|---|---|---|---|---|---|---|
\((-1 : -1 : 1) + (0 : -1 : 1) - 2 \cdot(1 : 0 : 0)\) | \(x (x + z)\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(-z^3\) | \(0.421492\) | \(\infty\) |
\((0 : -1 : 1) - (1 : 0 : 0)\) | \(x\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(-z^3\) | \(0.121889\) | \(\infty\) |
\(D_0 - 2 \cdot(1 : 0 : 0)\) | \(2x^2 + 2xz + z^2\) | \(=\) | \(0,\) | \(2y\) | \(=\) | \(-z^3\) | \(0\) | \(2\) |
Generator | $D_0$ | Height | Order | |||||
---|---|---|---|---|---|---|---|---|
\((-1 : -1 : 1) + (0 : -1 : 1) - 2 \cdot(1 : 0 : 0)\) | \(x (x + z)\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(-z^3\) | \(0.421492\) | \(\infty\) |
\((0 : -1 : 1) - (1 : 0 : 0)\) | \(x\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(-z^3\) | \(0.121889\) | \(\infty\) |
\(D_0 - 2 \cdot(1 : 0 : 0)\) | \(2x^2 + 2xz + z^2\) | \(=\) | \(0,\) | \(2y\) | \(=\) | \(-z^3\) | \(0\) | \(2\) |
BSD invariants
Hasse-Weil conjecture: | unverified |
Analytic rank: | \(2\) |
Mordell-Weil rank: | \(2\) |
2-Selmer rank: | \(3\) |
Regulator: | \( 0.047868 \) |
Real period: | \( 12.98001 \) |
Tamagawa product: | \( 4 \) |
Torsion order: | \( 2 \) |
Leading coefficient: | \( 0.621329 \) |
Analytic order of Ш: | \( 1 \) (rounded) |
Order of Ш: | square |
Local invariants
Prime | ord(\(N\)) | ord(\(\Delta\)) | Tamagawa | L-factor | Cluster picture |
---|---|---|---|---|---|
\(2\) | \(8\) | \(9\) | \(2\) | \(1 + 2 T + 2 T^{2}\) | |
\(5\) | \(1\) | \(2\) | \(2\) | \(( 1 - T )( 1 + 4 T + 5 T^{2} )\) | |
\(19\) | \(1\) | \(1\) | \(1\) | \(( 1 - T )( 1 + 6 T + 19 T^{2} )\) |
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? |
---|---|---|
\(2\) | 2.60.1 | 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);