Minimal equation
Minimal equation
Simplified equation
$y^2 + xy = x^6 - 2x^5 + x^3 + x^2 - 2x + 1$ | (homogenize, simplify) |
$y^2 + xz^2y = x^6 - 2x^5z + x^3z^3 + x^2z^4 - 2xz^5 + z^6$ | (dehomogenize, simplify) |
$y^2 = 4x^6 - 8x^5 + 4x^3 + 5x^2 - 8x + 4$ | (homogenize, minimize) |
sage: R.<x> = PolynomialRing(QQ); C = HyperellipticCurve(R([1, -2, 1, 1, 0, -2, 1]), R([0, 1]));
magma: R<x> := PolynomialRing(Rationals()); C := HyperellipticCurve(R![1, -2, 1, 1, 0, -2, 1], R![0, 1]);
sage: X = HyperellipticCurve(R([4, -8, 5, 4, 0, -8, 4]))
magma: X,pi:= SimplifiedModel(C);
Invariants
Conductor: | \( N \) | \(=\) | \(18080\) | \(=\) | \( 2^{5} \cdot 5 \cdot 113 \) | magma: Conductor(LSeries(C)); Factorization($1);
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Discriminant: | \( \Delta \) | \(=\) | \(-723200\) | \(=\) | \( - 2^{8} \cdot 5^{2} \cdot 113 \) | magma: Discriminant(C); Factorization(Integers()!$1);
|
Igusa-Clebsch invariants
Igusa invariants
G2 invariants
\( I_2 \) | \(=\) | \(148\) | \(=\) | \( 2^{2} \cdot 37 \) |
\( I_4 \) | \(=\) | \(2917\) | \(=\) | \( 2917 \) |
\( I_6 \) | \(=\) | \(148783\) | \(=\) | \( 148783 \) |
\( I_{10} \) | \(=\) | \(90400\) | \(=\) | \( 2^{5} \cdot 5^{2} \cdot 113 \) |
\( J_2 \) | \(=\) | \(148\) | \(=\) | \( 2^{2} \cdot 37 \) |
\( J_4 \) | \(=\) | \(-1032\) | \(=\) | \( - 2^{3} \cdot 3 \cdot 43 \) |
\( J_6 \) | \(=\) | \(-44800\) | \(=\) | \( - 2^{8} \cdot 5^{2} \cdot 7 \) |
\( J_8 \) | \(=\) | \(-1923856\) | \(=\) | \( - 2^{4} \cdot 11 \cdot 17 \cdot 643 \) |
\( J_{10} \) | \(=\) | \(723200\) | \(=\) | \( 2^{8} \cdot 5^{2} \cdot 113 \) |
\( g_1 \) | \(=\) | \(277375828/2825\) | ||
\( g_2 \) | \(=\) | \(-13068474/2825\) | ||
\( g_3 \) | \(=\) | \(-153328/113\) |
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 | |||||
---|---|---|---|---|---|
\((1 : -1 : 0)\) | \((1 : 1 : 0)\) | \((0 : -1 : 1)\) | \((0 : 1 : 1)\) | \((1 : 0 : 1)\) | \((1 : -1 : 1)\) |
\((-1 : -2 : 1)\) | \((-1 : 3 : 1)\) | \((1 : 3 : 2)\) | \((3 : -1 : 2)\) | \((1 : -7 : 2)\) | \((3 : -11 : 2)\) |
\((7 : -41 : 6)\) | \((7 : -211 : 6)\) |
Known points | |||||
---|---|---|---|---|---|
\((1 : -1 : 0)\) | \((1 : 1 : 0)\) | \((0 : -1 : 1)\) | \((0 : 1 : 1)\) | \((1 : 0 : 1)\) | \((1 : -1 : 1)\) |
\((-1 : -2 : 1)\) | \((-1 : 3 : 1)\) | \((1 : 3 : 2)\) | \((3 : -1 : 2)\) | \((1 : -7 : 2)\) | \((3 : -11 : 2)\) |
\((7 : -41 : 6)\) | \((7 : -211 : 6)\) |
Known points | |||||
---|---|---|---|---|---|
\((1 : -2 : 0)\) | \((1 : 2 : 0)\) | \((1 : -1 : 1)\) | \((1 : 1 : 1)\) | \((0 : -2 : 1)\) | \((0 : 2 : 1)\) |
\((-1 : -5 : 1)\) | \((-1 : 5 : 1)\) | \((1 : -10 : 2)\) | \((1 : 10 : 2)\) | \((3 : -10 : 2)\) | \((3 : 10 : 2)\) |
\((7 : -170 : 6)\) | \((7 : 170 : 6)\) |
magma: [C![-1,-2,1],C![-1,3,1],C![0,-1,1],C![0,1,1],C![1,-7,2],C![1,-1,0],C![1,-1,1],C![1,0,1],C![1,1,0],C![1,3,2],C![3,-11,2],C![3,-1,2],C![7,-211,6],C![7,-41,6]]; // minimal model
magma: [C![-1,-5,1],C![-1,5,1],C![0,-2,1],C![0,2,1],C![1,-10,2],C![1,-2,0],C![1,-1,1],C![1,1,1],C![1,2,0],C![1,10,2],C![3,-10,2],C![3,10,2],C![7,-170,6],C![7,170,6]]; // 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: \(\Z \oplus \Z \oplus \Z/{2}\Z\)
magma: MordellWeilGroupGenus2(Jacobian(C));
Generator | $D_0$ | Height | Order | |||||
---|---|---|---|---|---|---|---|---|
\((0 : -1 : 1) - (1 : 1 : 0)\) | \(z x\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(-x^3 - z^3\) | \(0.557085\) | \(\infty\) |
\((0 : -1 : 1) + (3 : -11 : 2) - (1 : -1 : 0) - (1 : 1 : 0)\) | \(x (2x - 3z)\) | \(=\) | \(0,\) | \(4y\) | \(=\) | \(-xz^2 - 4z^3\) | \(0.039896\) | \(\infty\) |
\(D_0 - (1 : -1 : 0) - (1 : 1 : 0)\) | \(2x^2 - 2xz + z^2\) | \(=\) | \(0,\) | \(2y\) | \(=\) | \(-xz^2\) | \(0\) | \(2\) |
Generator | $D_0$ | Height | Order | |||||
---|---|---|---|---|---|---|---|---|
\((0 : -1 : 1) - (1 : 1 : 0)\) | \(z x\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(-x^3 - z^3\) | \(0.557085\) | \(\infty\) |
\((0 : -1 : 1) + (3 : -11 : 2) - (1 : -1 : 0) - (1 : 1 : 0)\) | \(x (2x - 3z)\) | \(=\) | \(0,\) | \(4y\) | \(=\) | \(-xz^2 - 4z^3\) | \(0.039896\) | \(\infty\) |
\(D_0 - (1 : -1 : 0) - (1 : 1 : 0)\) | \(2x^2 - 2xz + z^2\) | \(=\) | \(0,\) | \(2y\) | \(=\) | \(-xz^2\) | \(0\) | \(2\) |
Generator | $D_0$ | Height | Order | |||||
---|---|---|---|---|---|---|---|---|
\((0 : -2 : 1) - (1 : 2 : 0)\) | \(z x\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(-2x^3 + xz^2 - 2z^3\) | \(0.557085\) | \(\infty\) |
\(2 \cdot(0 : -2 : 1) - (1 : -2 : 0) - (1 : 2 : 0)\) | \(x (2x - 3z)\) | \(=\) | \(0,\) | \(4y\) | \(=\) | \(-xz^2 - 8z^3\) | \(0.039896\) | \(\infty\) |
\(D_0 - (1 : -2 : 0) - (1 : 2 : 0)\) | \(2x^2 - 2xz + z^2\) | \(=\) | \(0,\) | \(2y\) | \(=\) | \(-xz^2\) | \(0\) | \(2\) |
BSD invariants
Hasse-Weil conjecture: | unverified |
Analytic rank: | \(2\) |
Mordell-Weil rank: | \(2\) |
2-Selmer rank: | \(3\) |
Regulator: | \( 0.022196 \) |
Real period: | \( 14.76743 \) |
Tamagawa product: | \( 8 \) |
Torsion order: | \( 2 \) |
Leading coefficient: | \( 0.655575 \) |
Analytic order of Ш: | \( 1 \) (rounded) |
Order of Ш: | square |
Local invariants
Prime | ord(\(N\)) | ord(\(\Delta\)) | Tamagawa | L-factor | Cluster picture |
---|---|---|---|---|---|
\(2\) | \(5\) | \(8\) | \(4\) | \(1 + T\) | |
\(5\) | \(1\) | \(2\) | \(2\) | \(( 1 + T )( 1 + 2 T + 5 T^{2} )\) | |
\(113\) | \(1\) | \(1\) | \(1\) | \(( 1 + T )( 1 + 14 T + 113 T^{2} )\) |
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? |
---|---|---|
\(2\) | 2.90.1 | 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);