Minimal equation
Minimal equation
Simplified equation
$y^2 + x^3y = 4x^3 + 8x^2 + 5x + 1$ | (homogenize, simplify) |
$y^2 + x^3y = 4x^3z^3 + 8x^2z^4 + 5xz^5 + z^6$ | (dehomogenize, simplify) |
$y^2 = x^6 + 16x^3 + 32x^2 + 20x + 4$ | (homogenize, minimize) |
sage: R.<x> = PolynomialRing(QQ); C = HyperellipticCurve(R([1, 5, 8, 4]), R([0, 0, 0, 1]));
magma: R<x> := PolynomialRing(Rationals()); C := HyperellipticCurve(R![1, 5, 8, 4], R![0, 0, 0, 1]);
sage: X = HyperellipticCurve(R([4, 20, 32, 16, 0, 0, 1]))
magma: X,pi:= SimplifiedModel(C);
Invariants
Conductor: | \( N \) | \(=\) | \(9331\) | \(=\) | \( 7 \cdot 31 \cdot 43 \) | magma: Conductor(LSeries(C)); Factorization($1);
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Discriminant: | \( \Delta \) | \(=\) | \(-9331\) | \(=\) | \( - 7 \cdot 31 \cdot 43 \) | magma: Discriminant(C); Factorization(Integers()!$1);
|
Igusa-Clebsch invariants
Igusa invariants
G2 invariants
\( I_2 \) | \(=\) | \(144\) | \(=\) | \( 2^{4} \cdot 3^{2} \) |
\( I_4 \) | \(=\) | \(5460\) | \(=\) | \( 2^{2} \cdot 3 \cdot 5 \cdot 7 \cdot 13 \) |
\( I_6 \) | \(=\) | \(156888\) | \(=\) | \( 2^{3} \cdot 3^{2} \cdot 2179 \) |
\( I_{10} \) | \(=\) | \(-37324\) | \(=\) | \( - 2^{2} \cdot 7 \cdot 31 \cdot 43 \) |
\( J_2 \) | \(=\) | \(72\) | \(=\) | \( 2^{3} \cdot 3^{2} \) |
\( J_4 \) | \(=\) | \(-694\) | \(=\) | \( - 2 \cdot 347 \) |
\( J_6 \) | \(=\) | \(1632\) | \(=\) | \( 2^{5} \cdot 3 \cdot 17 \) |
\( J_8 \) | \(=\) | \(-91033\) | \(=\) | \( -91033 \) |
\( J_{10} \) | \(=\) | \(-9331\) | \(=\) | \( - 7 \cdot 31 \cdot 43 \) |
\( g_1 \) | \(=\) | \(-1934917632/9331\) | ||
\( g_2 \) | \(=\) | \(259034112/9331\) | ||
\( g_3 \) | \(=\) | \(-8460288/9331\) |
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 | |||||
---|---|---|---|---|---|
\((1 : 0 : 0)\) | \((1 : -1 : 0)\) | \((-1 : 0 : 1)\) | \((0 : -1 : 1)\) | \((0 : 1 : 1)\) | \((-1 : 1 : 1)\) |
\((-1 : 0 : 2)\) | \((-1 : 1 : 2)\) | \((-3 : 2 : 1)\) | \((-3 : 25 : 1)\) | \((-5 : 27 : 3)\) | \((-5 : 98 : 3)\) |
Known points | |||||
---|---|---|---|---|---|
\((1 : 0 : 0)\) | \((1 : -1 : 0)\) | \((-1 : 0 : 1)\) | \((0 : -1 : 1)\) | \((0 : 1 : 1)\) | \((-1 : 1 : 1)\) |
\((-1 : 0 : 2)\) | \((-1 : 1 : 2)\) | \((-3 : 2 : 1)\) | \((-3 : 25 : 1)\) | \((-5 : 27 : 3)\) | \((-5 : 98 : 3)\) |
Known points | |||||
---|---|---|---|---|---|
\((1 : -1 : 0)\) | \((1 : 1 : 0)\) | \((-1 : -1 : 1)\) | \((-1 : 1 : 1)\) | \((0 : -2 : 1)\) | \((0 : 2 : 1)\) |
\((-1 : -1 : 2)\) | \((-1 : 1 : 2)\) | \((-3 : -23 : 1)\) | \((-3 : 23 : 1)\) | \((-5 : -71 : 3)\) | \((-5 : 71 : 3)\) |
magma: [C![-5,27,3],C![-5,98,3],C![-3,2,1],C![-3,25,1],C![-1,0,1],C![-1,0,2],C![-1,1,1],C![-1,1,2],C![0,-1,1],C![0,1,1],C![1,-1,0],C![1,0,0]]; // minimal model
magma: [C![-5,-71,3],C![-5,71,3],C![-3,-23,1],C![-3,23,1],C![-1,-1,1],C![-1,-1,2],C![-1,1,1],C![-1,1,2],C![0,-2,1],C![0,2,1],C![1,-1,0],C![1,1,0]]; // 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: \(\Z \oplus \Z\)
magma: MordellWeilGroupGenus2(Jacobian(C));
Generator | $D_0$ | Height | Order | |||||
---|---|---|---|---|---|---|---|---|
\((-1 : 0 : 1) + (0 : 1 : 1) - (1 : -1 : 0) - (1 : 0 : 0)\) | \(x (x + z)\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(xz^2 + z^3\) | \(0.181039\) | \(\infty\) |
\((-1 : 1 : 2) - (1 : 0 : 0)\) | \(z (2x + z)\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(-x^3\) | \(0.083081\) | \(\infty\) |
Generator | $D_0$ | Height | Order | |||||
---|---|---|---|---|---|---|---|---|
\((-1 : 0 : 1) + (0 : 1 : 1) - (1 : -1 : 0) - (1 : 0 : 0)\) | \(x (x + z)\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(xz^2 + z^3\) | \(0.181039\) | \(\infty\) |
\((-1 : 1 : 2) - (1 : 0 : 0)\) | \(z (2x + z)\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(-x^3\) | \(0.083081\) | \(\infty\) |
Generator | $D_0$ | Height | Order | |||||
---|---|---|---|---|---|---|---|---|
\((-1 : -1 : 1) + (0 : 2 : 1) - (1 : -1 : 0) - (1 : 1 : 0)\) | \(x (x + z)\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(x^3 + 2xz^2 + 2z^3\) | \(0.181039\) | \(\infty\) |
\((-1 : 1 : 2) - (1 : 1 : 0)\) | \(z (2x + z)\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(-x^3\) | \(0.083081\) | \(\infty\) |
BSD invariants
Hasse-Weil conjecture: | unverified |
Analytic rank: | \(2\) |
Mordell-Weil rank: | \(2\) |
2-Selmer rank: | \(2\) |
Regulator: | \( 0.014985 \) |
Real period: | \( 26.23760 \) |
Tamagawa product: | \( 1 \) |
Torsion order: | \( 1 \) |
Leading coefficient: | \( 0.393188 \) |
Analytic order of Ш: | \( 1 \) (rounded) |
Order of Ш: | square |
Local invariants
Prime | ord(\(N\)) | ord(\(\Delta\)) | Tamagawa | L-factor | Cluster picture |
---|---|---|---|---|---|
\(7\) | \(1\) | \(1\) | \(1\) | \(( 1 - T )( 1 + 5 T + 7 T^{2} )\) | |
\(31\) | \(1\) | \(1\) | \(1\) | \(( 1 + T )( 1 + T + 31 T^{2} )\) | |
\(43\) | \(1\) | \(1\) | \(1\) | \(( 1 - T )( 1 - 6 T + 43 T^{2} )\) |
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);