Minimal equation
Minimal equation
Simplified equation
$y^2 + (x^3 + x^2)y = x^5 + 2x^4 - x - 3$ | (homogenize, simplify) |
$y^2 + (x^3 + x^2z)y = x^5z + 2x^4z^2 - xz^5 - 3z^6$ | (dehomogenize, simplify) |
$y^2 = x^6 + 6x^5 + 9x^4 - 4x - 12$ | (homogenize, minimize) |
sage: R.<x> = PolynomialRing(QQ); C = HyperellipticCurve(R([-3, -1, 0, 0, 2, 1]), R([0, 0, 1, 1]));
magma: R<x> := PolynomialRing(Rationals()); C := HyperellipticCurve(R![-3, -1, 0, 0, 2, 1], R![0, 0, 1, 1]);
sage: X = HyperellipticCurve(R([-12, -4, 0, 0, 9, 6, 1]))
magma: X,pi:= SimplifiedModel(C);
Invariants
Conductor: | \( N \) | \(=\) | \(731\) | \(=\) | \( 17 \cdot 43 \) | magma: Conductor(LSeries(C)); Factorization($1);
|
Discriminant: | \( \Delta \) | \(=\) | \(-12427\) | \(=\) | \( - 17^{2} \cdot 43 \) | magma: Discriminant(C); Factorization(Integers()!$1);
|
Igusa-Clebsch invariants
Igusa invariants
G2 invariants
\( I_2 \) | \(=\) | \(480\) | \(=\) | \( 2^{5} \cdot 3 \cdot 5 \) |
\( I_4 \) | \(=\) | \(-21564\) | \(=\) | \( - 2^{2} \cdot 3^{2} \cdot 599 \) |
\( I_6 \) | \(=\) | \(-3373785\) | \(=\) | \( - 3^{3} \cdot 5 \cdot 67 \cdot 373 \) |
\( I_{10} \) | \(=\) | \(-49708\) | \(=\) | \( - 2^{2} \cdot 17^{2} \cdot 43 \) |
\( J_2 \) | \(=\) | \(240\) | \(=\) | \( 2^{4} \cdot 3 \cdot 5 \) |
\( J_4 \) | \(=\) | \(5994\) | \(=\) | \( 2 \cdot 3^{4} \cdot 37 \) |
\( J_6 \) | \(=\) | \(167265\) | \(=\) | \( 3^{4} \cdot 5 \cdot 7 \cdot 59 \) |
\( J_8 \) | \(=\) | \(1053891\) | \(=\) | \( 3^{5} \cdot 4337 \) |
\( J_{10} \) | \(=\) | \(-12427\) | \(=\) | \( - 17^{2} \cdot 43 \) |
\( g_1 \) | \(=\) | \(-796262400000/12427\) | ||
\( g_2 \) | \(=\) | \(-82861056000/12427\) | ||
\( g_3 \) | \(=\) | \(-9634464000/12427\) |
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
All points: \((1 : 0 : 0),\, (1 : -1 : 0),\, (1 : -1 : 1),\, (-3 : 9 : 1)\)
magma: [C![-3,9,1],C![1,-1,0],C![1,-1,1],C![1,0,0]]; // minimal model
magma: [C![-3,0,1],C![1,-1,0],C![1,0,1],C![1,1,0]]; // simplified model
Number of rational Weierstrass points: \(2\)
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: \(\Z/{10}\Z\)
magma: MordellWeilGroupGenus2(Jacobian(C));
Generator | $D_0$ | Height | Order | |||||
---|---|---|---|---|---|---|---|---|
\(D_0 - (1 : -1 : 0) - (1 : 0 : 0)\) | \(2x^2 + 8xz + 7z^2\) | \(=\) | \(0,\) | \(2y\) | \(=\) | \(-8xz^2 - 11z^3\) | \(0\) | \(10\) |
Generator | $D_0$ | Height | Order | |||||
---|---|---|---|---|---|---|---|---|
\(D_0 - (1 : -1 : 0) - (1 : 0 : 0)\) | \(2x^2 + 8xz + 7z^2\) | \(=\) | \(0,\) | \(2y\) | \(=\) | \(-8xz^2 - 11z^3\) | \(0\) | \(10\) |
Generator | $D_0$ | Height | Order | |||||
---|---|---|---|---|---|---|---|---|
\(D_0 - (1 : -1 : 0) - (1 : 1 : 0)\) | \(2x^2 + 8xz + 7z^2\) | \(=\) | \(0,\) | \(2y\) | \(=\) | \(x^3 + x^2z - 16xz^2 - 22z^3\) | \(0\) | \(10\) |
BSD invariants
Hasse-Weil conjecture: | unverified |
Analytic rank: | \(0\) |
Mordell-Weil rank: | \(0\) |
2-Selmer rank: | \(1\) |
Regulator: | \( 1 \) |
Real period: | \( 14.92677 \) |
Tamagawa product: | \( 2 \) |
Torsion order: | \( 10 \) |
Leading coefficient: | \( 0.298535 \) |
Analytic order of Ш: | \( 1 \) (rounded) |
Order of Ш: | square |
Local invariants
Prime | ord(\(N\)) | ord(\(\Delta\)) | Tamagawa | L-factor | Cluster picture |
---|---|---|---|---|---|
\(17\) | \(1\) | \(2\) | \(2\) | \(( 1 + T )( 1 - 3 T + 17 T^{2} )\) | |
\(43\) | \(1\) | \(1\) | \(1\) | \(( 1 + T )( 1 - 4 T + 43 T^{2} )\) |
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? |
---|---|---|
\(2\) | 2.30.3 | yes |
\(5\) | not computed | 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);