Minimal equation
Minimal equation
Simplified equation
$y^2 + xy = -x^6 - 2x^5 - 2x^4 - x^3 + x^2 + 2x - 1$ | (homogenize, simplify) |
$y^2 + xz^2y = -x^6 - 2x^5z - 2x^4z^2 - x^3z^3 + x^2z^4 + 2xz^5 - z^6$ | (dehomogenize, simplify) |
$y^2 = -4x^6 - 8x^5 - 8x^4 - 4x^3 + 5x^2 + 8x - 4$ | (homogenize, minimize) |
sage: R.<x> = PolynomialRing(QQ); C = HyperellipticCurve(R([-1, 2, 1, -1, -2, -2, -1]), R([0, 1]));
magma: R<x> := PolynomialRing(Rationals()); C := HyperellipticCurve(R![-1, 2, 1, -1, -2, -2, -1], R![0, 1]);
sage: X = HyperellipticCurve(R([-4, 8, 5, -4, -8, -8, -4]))
magma: X,pi:= SimplifiedModel(C);
Invariants
Conductor: | \( N \) | \(=\) | \(129600\) | \(=\) | \( 2^{6} \cdot 3^{4} \cdot 5^{2} \) | magma: Conductor(LSeries(C)); Factorization($1);
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Discriminant: | \( \Delta \) | \(=\) | \(129600\) | \(=\) | \( 2^{6} \cdot 3^{4} \cdot 5^{2} \) | magma: Discriminant(C); Factorization(Integers()!$1);
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Igusa-Clebsch invariants
Igusa invariants
G2 invariants
\( I_2 \) | \(=\) | \(708\) | \(=\) | \( 2^{2} \cdot 3 \cdot 59 \) |
\( I_4 \) | \(=\) | \(16335\) | \(=\) | \( 3^{3} \cdot 5 \cdot 11^{2} \) |
\( I_6 \) | \(=\) | \(3582090\) | \(=\) | \( 2 \cdot 3^{3} \cdot 5 \cdot 13267 \) |
\( I_{10} \) | \(=\) | \(-16200\) | \(=\) | \( - 2^{3} \cdot 3^{4} \cdot 5^{2} \) |
\( J_2 \) | \(=\) | \(708\) | \(=\) | \( 2^{2} \cdot 3 \cdot 59 \) |
\( J_4 \) | \(=\) | \(9996\) | \(=\) | \( 2^{2} \cdot 3 \cdot 7^{2} \cdot 17 \) |
\( J_6 \) | \(=\) | \(-220864\) | \(=\) | \( - 2^{6} \cdot 7 \cdot 17 \cdot 29 \) |
\( J_8 \) | \(=\) | \(-64072932\) | \(=\) | \( - 2^{2} \cdot 3 \cdot 7 \cdot 11 \cdot 17 \cdot 4079 \) |
\( J_{10} \) | \(=\) | \(-129600\) | \(=\) | \( - 2^{6} \cdot 3^{4} \cdot 5^{2} \) |
\( g_1 \) | \(=\) | \(-34316366352/25\) | ||
\( g_2 \) | \(=\) | \(-684322828/25\) | ||
\( g_3 \) | \(=\) | \(192206896/225\) |
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
This curve has no rational points.
magma: []; // minimal model
magma: []; // simplified model
Number of rational Weierstrass points: \(0\)
magma: #Roots(HyperellipticPolynomials(SimplifiedModel(C)));
This curve is locally solvable except over $\Q_{3}$.
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: trivial
magma: MordellWeilGroupGenus2(Jacobian(C));
2-torsion field: 9.1.34012224000000.6
BSD invariants
Hasse-Weil conjecture: | unverified |
Analytic rank: | \(0\) |
Mordell-Weil rank: | \(0\) |
2-Selmer rank: | \(0\) |
Regulator: | \( 1 \) |
Real period: | \( 2.045372 \) |
Tamagawa product: | \( 1 \) |
Torsion order: | \( 1 \) |
Leading coefficient: | \( 2.045372 \) |
Analytic order of Ш: | \( 1 \) (rounded) |
Order of Ш: | square |
Local invariants
Prime | ord(\(N\)) | ord(\(\Delta\)) | Tamagawa | L-factor | Cluster picture |
---|---|---|---|---|---|
\(2\) | \(6\) | \(6\) | \(1\) | \(1 + T\) | |
\(3\) | \(4\) | \(4\) | \(1\) | \(1 - 3 T + 3 T^{2}\) | |
\(5\) | \(2\) | \(2\) | \(1\) | \(1 + 2 T + 5 T^{2}\) |
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? |
---|---|---|
\(2\) | 2.40.1 | no |
\(3\) | 3.40.1 | no |
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);