Properties

Label 968.a.234256.1
Conductor $968$
Discriminant $-234256$
Mordell-Weil group \(\Z \oplus \Z/{5}\Z\)
Sato-Tate group $\mathrm{SU}(2)\times\mathrm{SU}(2)$
\(\End(J_{\overline{\Q}}) \otimes \R\) \(\R \times \R\)
\(\End(J_{\overline{\Q}}) \otimes \Q\) \(\Q \times \Q\)
\(\End(J) \otimes \Q\) \(\Q \times \Q\)
\(\overline{\Q}\)-simple no
\(\mathrm{GL}_2\)-type yes

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Minimal equation

Minimal equation

Simplified equation

$y^2 + x^3y = 6x^4 + 47x^2 + 121$ (homogenize, simplify)
$y^2 + x^3y = 6x^4z^2 + 47x^2z^4 + 121z^6$ (dehomogenize, simplify)
$y^2 = x^6 + 24x^4 + 188x^2 + 484$ (homogenize, minimize)

sage: R.<x> = PolynomialRing(QQ); C = HyperellipticCurve(R([121, 0, 47, 0, 6]), R([0, 0, 0, 1]));
 
magma: R<x> := PolynomialRing(Rationals()); C := HyperellipticCurve(R![121, 0, 47, 0, 6], R![0, 0, 0, 1]);
 
sage: X = HyperellipticCurve(R([484, 0, 188, 0, 24, 0, 1]))
 
magma: X,pi:= SimplifiedModel(C);
 

Invariants

Conductor: \( N \)  \(=\)  \(968\) \(=\) \( 2^{3} \cdot 11^{2} \)
magma: Conductor(LSeries(C)); Factorization($1);
 
Discriminant: \( \Delta \)  \(=\)  \(-234256\) \(=\) \( - 2^{4} \cdot 11^{4} \)
magma: Discriminant(C); Factorization(Integers()!$1);
 

Igusa-Clebsch invariants

Igusa invariants

G2 invariants

\( I_2 \)  \(=\) \(23544\) \(=\)  \( 2^{3} \cdot 3^{3} \cdot 109 \)
\( I_4 \)  \(=\) \(6117\) \(=\)  \( 3 \cdot 2039 \)
\( I_6 \)  \(=\) \(47655081\) \(=\)  \( 3^{3} \cdot 379 \cdot 4657 \)
\( I_{10} \)  \(=\) \(29282\) \(=\)  \( 2 \cdot 11^{4} \)
\( J_2 \)  \(=\) \(23544\) \(=\)  \( 2^{3} \cdot 3^{3} \cdot 109 \)
\( J_4 \)  \(=\) \(23092586\) \(=\)  \( 2 \cdot 11 \cdot 1049663 \)
\( J_6 \)  \(=\) \(30194746560\) \(=\)  \( 2^{6} \cdot 3^{2} \cdot 5 \cdot 11^{3} \cdot 7877 \)
\( J_8 \)  \(=\) \(44409396210311\) \(=\)  \( 11^{2} \cdot 977 \cdot 2311 \cdot 162553 \)
\( J_{10} \)  \(=\) \(234256\) \(=\)  \( 2^{4} \cdot 11^{4} \)
\( g_1 \)  \(=\) \(452148675314325387264/14641\)
\( g_2 \)  \(=\) \(1712381980706754624/1331\)
\( g_3 \)  \(=\) \(785948064456960/11\)

sage: C.igusa_clebsch_invariants(); [factor(a) for a in _]
 
magma: IgusaClebschInvariants(C); IgusaInvariants(C); G2Invariants(C);
 

Automorphism group

\(\mathrm{Aut}(X)\)\(\simeq\) $C_2^2$
magma: AutomorphismGroup(C); IdentifyGroup($1);
 
\(\mathrm{Aut}(X_{\overline{\Q}})\)\(\simeq\) $C_2^2$
magma: AutomorphismGroup(ChangeRing(C,AlgebraicClosure(Rationals()))); IdentifyGroup($1);
 

Rational points

All points: \((1 : 0 : 0),\, (1 : -1 : 0),\, (0 : -11 : 1),\, (0 : 11 : 1)\)
All points: \((1 : 0 : 0),\, (1 : -1 : 0),\, (0 : -11 : 1),\, (0 : 11 : 1)\)
All points: \((1 : -1 : 0),\, (1 : 1 : 0),\, (0 : -22 : 1),\, (0 : 22 : 1)\)

magma: [C![0,-11,1],C![0,11,1],C![1,-1,0],C![1,0,0]]; // minimal model
 
magma: [C![0,-22,1],C![0,22,1],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: \(\Z \oplus \Z/{5}\Z\)

magma: MordellWeilGroupGenus2(Jacobian(C));
 

Generator $D_0$ Height Order
\(D_0 - (1 : -1 : 0) - (1 : 0 : 0)\) \(x^2 + 6z^2\) \(=\) \(0,\) \(y\) \(=\) \(3xz^2 + z^3\) \(0.080528\) \(\infty\)
\(D_0 - 2 \cdot(1 : -1 : 0)\) \(z^2\) \(=\) \(0,\) \(y\) \(=\) \(0\) \(0\) \(5\)
Generator $D_0$ Height Order
\(D_0 - (1 : -1 : 0) - (1 : 0 : 0)\) \(x^2 + 6z^2\) \(=\) \(0,\) \(y\) \(=\) \(3xz^2 + z^3\) \(0.080528\) \(\infty\)
\(D_0 - 2 \cdot(1 : -1 : 0)\) \(z^2\) \(=\) \(0,\) \(y\) \(=\) \(0\) \(0\) \(5\)
Generator $D_0$ Height Order
\(D_0 - (1 : -1 : 0) - (1 : 1 : 0)\) \(x^2 + 6z^2\) \(=\) \(0,\) \(y\) \(=\) \(x^3 + 6xz^2 + 2z^3\) \(0.080528\) \(\infty\)
\(D_0 - 2 \cdot(1 : -1 : 0)\) \(z^2\) \(=\) \(0,\) \(y\) \(=\) \(x^3\) \(0\) \(5\)

2-torsion field: 6.0.30976.1

BSD invariants

Hasse-Weil conjecture: verified
Analytic rank: \(1\)
Mordell-Weil rank: \(1\)
2-Selmer rank:\(1\)
Regulator: \( 0.080528 \)
Real period: \( 5.397350 \)
Tamagawa product: \( 10 \)
Torsion order:\( 5 \)
Leading coefficient: \( 0.173856 \)
Analytic order of Ш: \( 1 \)   (rounded)
Order of Ш:square

Local invariants

Prime ord(\(N\)) ord(\(\Delta\)) Tamagawa L-factor Cluster picture
\(2\) \(3\) \(4\) \(2\) \(1 + 2 T + 2 T^{2}\)
\(11\) \(2\) \(4\) \(5\) \(( 1 - T )( 1 + T )\)

Galois representations

For primes $\ell \ge 5$ the Galois representation data has not been computed for this curve since it is not generic.

For primes $\ell \le 3$, the image of the mod-$\ell$ Galois representation is listed in the table below, whenever it is not all of $\GSp(4,\F_\ell)$.

Prime \(\ell\) mod-\(\ell\) image Is torsion prime?
\(2\) 2.60.2 no
\(3\) 3.90.1 no

Sato-Tate group

\(\mathrm{ST}\)\(\simeq\) $\mathrm{SU}(2)\times\mathrm{SU}(2)$
\(\mathrm{ST}^0\)\(\simeq\) \(\mathrm{SU}(2)\times\mathrm{SU}(2)\)

Decomposition of the Jacobian

Splits over \(\Q\)

Decomposes up to isogeny as the product of the non-isogenous elliptic curve isogeny classes:
  Elliptic curve isogeny class 88.a
  Elliptic curve isogeny class 11.a

magma: HeuristicDecompositionFactors(C);
 

Endomorphisms of the Jacobian

Of \(\GL_2\)-type over \(\Q\)

Endomorphism ring over \(\Q\):

\(\End (J_{})\)\(\simeq\)an order of index \(2\) in \(\Z \times \Z\)
\(\End (J_{}) \otimes \Q \)\(\simeq\)\(\Q\) \(\times\) \(\Q\)
\(\End (J_{}) \otimes \R\)\(\simeq\) \(\R \times \R\)

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);