Minimal equation
Minimal equation
Simplified equation
$y^2 + x^3y = 2x^3 - x^2 - 2x + 1$ | (homogenize, simplify) |
$y^2 + x^3y = 2x^3z^3 - x^2z^4 - 2xz^5 + z^6$ | (dehomogenize, simplify) |
$y^2 = x^6 + 8x^3 - 4x^2 - 8x + 4$ | (homogenize, minimize) |
sage: R.<x> = PolynomialRing(QQ); C = HyperellipticCurve(R([1, -2, -1, 2]), R([0, 0, 0, 1]));
magma: R<x> := PolynomialRing(Rationals()); C := HyperellipticCurve(R![1, -2, -1, 2], R![0, 0, 0, 1]);
sage: X = HyperellipticCurve(R([4, -8, -4, 8, 0, 0, 1]))
magma: X,pi:= SimplifiedModel(C);
Invariants
Conductor: | \( N \) | \(=\) | \(60916\) | \(=\) | \( 2^{2} \cdot 97 \cdot 157 \) | magma: Conductor(LSeries(C)); Factorization($1);
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Discriminant: | \( \Delta \) | \(=\) | \(-243664\) | \(=\) | \( - 2^{4} \cdot 97 \cdot 157 \) | magma: Discriminant(C); Factorization(Integers()!$1);
|
Igusa-Clebsch invariants
Igusa invariants
G2 invariants
\( I_2 \) | \(=\) | \(72\) | \(=\) | \( 2^{3} \cdot 3^{2} \) |
\( I_4 \) | \(=\) | \(933\) | \(=\) | \( 3 \cdot 311 \) |
\( I_6 \) | \(=\) | \(50337\) | \(=\) | \( 3^{2} \cdot 7 \cdot 17 \cdot 47 \) |
\( I_{10} \) | \(=\) | \(30458\) | \(=\) | \( 2 \cdot 97 \cdot 157 \) |
\( J_2 \) | \(=\) | \(72\) | \(=\) | \( 2^{3} \cdot 3^{2} \) |
\( J_4 \) | \(=\) | \(-406\) | \(=\) | \( - 2 \cdot 7 \cdot 29 \) |
\( J_6 \) | \(=\) | \(-31440\) | \(=\) | \( - 2^{4} \cdot 3 \cdot 5 \cdot 131 \) |
\( J_8 \) | \(=\) | \(-607129\) | \(=\) | \( -607129 \) |
\( J_{10} \) | \(=\) | \(243664\) | \(=\) | \( 2^{4} \cdot 97 \cdot 157 \) |
\( g_1 \) | \(=\) | \(120932352/15229\) | ||
\( g_2 \) | \(=\) | \(-9471168/15229\) | ||
\( g_3 \) | \(=\) | \(-10186560/15229\) |
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);
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\(\mathrm{Aut}(X_{\overline{\Q}})\) | \(\simeq\) | $C_2$ | magma: AutomorphismGroup(ChangeRing(C,AlgebraicClosure(Rationals()))); IdentifyGroup($1);
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Rational points
Known points | |||||
---|---|---|---|---|---|
\((1 : 0 : 0)\) | \((1 : -1 : 0)\) | \((-1 : 0 : 1)\) | \((0 : -1 : 1)\) | \((0 : 1 : 1)\) | \((1 : 0 : 1)\) |
\((-1 : 1 : 1)\) | \((1 : -1 : 1)\) | \((1 : 0 : 2)\) | \((1 : -1 : 2)\) | \((2 : 1 : 1)\) | \((-2 : 3 : 1)\) |
\((-2 : 5 : 1)\) | \((3 : 5 : 2)\) | \((2 : -9 : 1)\) | \((-2 : -27 : 3)\) | \((3 : -32 : 2)\) | \((-2 : 35 : 3)\) |
\((-7 : -31625 : 30)\) | \((-7 : 31968 : 30)\) |
Known points | |||||
---|---|---|---|---|---|
\((1 : 0 : 0)\) | \((1 : -1 : 0)\) | \((-1 : 0 : 1)\) | \((0 : -1 : 1)\) | \((0 : 1 : 1)\) | \((1 : 0 : 1)\) |
\((-1 : 1 : 1)\) | \((1 : -1 : 1)\) | \((1 : 0 : 2)\) | \((1 : -1 : 2)\) | \((2 : 1 : 1)\) | \((-2 : 3 : 1)\) |
\((-2 : 5 : 1)\) | \((3 : 5 : 2)\) | \((2 : -9 : 1)\) | \((-2 : -27 : 3)\) | \((3 : -32 : 2)\) | \((-2 : 35 : 3)\) |
\((-7 : -31625 : 30)\) | \((-7 : 31968 : 30)\) |
Known points | |||||
---|---|---|---|---|---|
\((1 : -1 : 0)\) | \((1 : 1 : 0)\) | \((-1 : -1 : 1)\) | \((-1 : 1 : 1)\) | \((1 : -1 : 1)\) | \((1 : 1 : 1)\) |
\((0 : -2 : 1)\) | \((0 : 2 : 1)\) | \((1 : -1 : 2)\) | \((1 : 1 : 2)\) | \((-2 : -2 : 1)\) | \((-2 : 2 : 1)\) |
\((2 : -10 : 1)\) | \((2 : 10 : 1)\) | \((3 : -37 : 2)\) | \((3 : 37 : 2)\) | \((-2 : -62 : 3)\) | \((-2 : 62 : 3)\) |
\((-7 : -63593 : 30)\) | \((-7 : 63593 : 30)\) |
magma: [C![-7,-31625,30],C![-7,31968,30],C![-2,-27,3],C![-2,3,1],C![-2,5,1],C![-2,35,3],C![-1,0,1],C![-1,1,1],C![0,-1,1],C![0,1,1],C![1,-1,0],C![1,-1,1],C![1,-1,2],C![1,0,0],C![1,0,1],C![1,0,2],C![2,-9,1],C![2,1,1],C![3,-32,2],C![3,5,2]]; // minimal model
magma: [C![-7,-63593,30],C![-7,63593,30],C![-2,-62,3],C![-2,-2,1],C![-2,2,1],C![-2,62,3],C![-1,-1,1],C![-1,1,1],C![0,-2,1],C![0,2,1],C![1,-1,0],C![1,-1,1],C![1,-1,2],C![1,1,0],C![1,1,1],C![1,1,2],C![2,-10,1],C![2,10,1],C![3,-37,2],C![3,37,2]]; // simplified model
Number of rational Weierstrass points: \(0\)
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: \(\Z \oplus \Z \oplus \Z\)
magma: MordellWeilGroupGenus2(Jacobian(C));
Generator | $D_0$ | Height | Order | |||||
---|---|---|---|---|---|---|---|---|
\((0 : 1 : 1) + (1 : -1 : 1) - (1 : -1 : 0) - (1 : 0 : 0)\) | \(x (x - z)\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(-2xz^2 + z^3\) | \(0.457175\) | \(\infty\) |
\((0 : -1 : 1) - (1 : -1 : 0)\) | \(z x\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(-z^3\) | \(0.301854\) | \(\infty\) |
\((0 : -1 : 1) - (1 : 0 : 0)\) | \(z x\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(-x^3 - z^3\) | \(0.110995\) | \(\infty\) |
Generator | $D_0$ | Height | Order | |||||
---|---|---|---|---|---|---|---|---|
\((0 : 1 : 1) + (1 : -1 : 1) - (1 : -1 : 0) - (1 : 0 : 0)\) | \(x (x - z)\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(-2xz^2 + z^3\) | \(0.457175\) | \(\infty\) |
\((0 : -1 : 1) - (1 : -1 : 0)\) | \(z x\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(-z^3\) | \(0.301854\) | \(\infty\) |
\((0 : -1 : 1) - (1 : 0 : 0)\) | \(z x\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(-x^3 - z^3\) | \(0.110995\) | \(\infty\) |
Generator | $D_0$ | Height | Order | |||||
---|---|---|---|---|---|---|---|---|
\((0 : 2 : 1) + (1 : -1 : 1) - (1 : -1 : 0) - (1 : 1 : 0)\) | \(x (x - z)\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(x^3 - 4xz^2 + 2z^3\) | \(0.457175\) | \(\infty\) |
\((0 : -2 : 1) - (1 : -1 : 0)\) | \(z x\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(x^3 - 2z^3\) | \(0.301854\) | \(\infty\) |
\((0 : -2 : 1) - (1 : 1 : 0)\) | \(z x\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(-x^3 - 2z^3\) | \(0.110995\) | \(\infty\) |
2-torsion field: 6.4.3898624.1
BSD invariants
Hasse-Weil conjecture: | unverified |
Analytic rank: | \(3\) (upper bound) |
Mordell-Weil rank: | \(3\) |
2-Selmer rank: | \(3\) |
Regulator: | \( 0.014488 \) |
Real period: | \( 16.65934 \) |
Tamagawa product: | \( 3 \) |
Torsion order: | \( 1 \) |
Leading coefficient: | \( 0.724083 \) |
Analytic order of Ш: | \( 1 \) (rounded) |
Order of Ш: | square |
Local invariants
Prime | ord(\(N\)) | ord(\(\Delta\)) | Tamagawa | L-factor | Cluster picture |
---|---|---|---|---|---|
\(2\) | \(2\) | \(4\) | \(3\) | \(1 + 2 T + 2 T^{2}\) | |
\(97\) | \(1\) | \(1\) | \(1\) | \(( 1 - T )( 1 + 12 T + 97 T^{2} )\) | |
\(157\) | \(1\) | \(1\) | \(1\) | \(( 1 - T )( 1 + 2 T + 157 T^{2} )\) |
Galois representations
The mod-$\ell$ Galois representation has maximal image \(\GSp(4,\F_\ell)\) for all primes \( \ell \) .
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);