Properties

Label 1944.a.34992.1
Conductor $1944$
Discriminant $-34992$
Mordell-Weil group \(\Z/{2}\Z \oplus \Z/{6}\Z\)
Sato-Tate group $\mathrm{USp}(4)$
\(\End(J_{\overline{\Q}}) \otimes \R\) \(\R\)
\(\End(J_{\overline{\Q}}) \otimes \Q\) \(\Q\)
\(\End(J) \otimes \Q\) \(\Q\)
\(\overline{\Q}\)-simple yes
\(\mathrm{GL}_2\)-type no

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Minimal equation

Minimal equation

Simplified equation

$y^2 + xy = 2x^5 + 2x^4 - 3x^2 + x$ (homogenize, simplify)
$y^2 + xz^2y = 2x^5z + 2x^4z^2 - 3x^2z^4 + xz^5$ (dehomogenize, simplify)
$y^2 = 8x^5 + 8x^4 - 11x^2 + 4x$ (homogenize, minimize)

sage: R.<x> = PolynomialRing(QQ); C = HyperellipticCurve(R([0, 1, -3, 0, 2, 2]), R([0, 1]));
 
magma: R<x> := PolynomialRing(Rationals()); C := HyperellipticCurve(R![0, 1, -3, 0, 2, 2], R![0, 1]);
 
sage: X = HyperellipticCurve(R([0, 4, -11, 0, 8, 8]))
 
magma: X,pi:= SimplifiedModel(C);
 

Invariants

Conductor: \( N \)  \(=\)  \(1944\) \(=\) \( 2^{3} \cdot 3^{5} \)
magma: Conductor(LSeries(C)); Factorization($1);
 
Discriminant: \( \Delta \)  \(=\)  \(-34992\) \(=\) \( - 2^{4} \cdot 3^{7} \)
magma: Discriminant(C); Factorization(Integers()!$1);
 

Igusa-Clebsch invariants

Igusa invariants

G2 invariants

\( I_2 \)  \(=\) \(224\) \(=\)  \( 2^{5} \cdot 7 \)
\( I_4 \)  \(=\) \(-432\) \(=\)  \( - 2^{4} \cdot 3^{3} \)
\( I_6 \)  \(=\) \(-16812\) \(=\)  \( - 2^{2} \cdot 3^{2} \cdot 467 \)
\( I_{10} \)  \(=\) \(-576\) \(=\)  \( - 2^{6} \cdot 3^{2} \)
\( J_2 \)  \(=\) \(336\) \(=\)  \( 2^{4} \cdot 3 \cdot 7 \)
\( J_4 \)  \(=\) \(5352\) \(=\)  \( 2^{3} \cdot 3 \cdot 223 \)
\( J_6 \)  \(=\) \(77764\) \(=\)  \( 2^{2} \cdot 19441 \)
\( J_8 \)  \(=\) \(-628800\) \(=\)  \( - 2^{6} \cdot 3 \cdot 5^{2} \cdot 131 \)
\( J_{10} \)  \(=\) \(-34992\) \(=\)  \( - 2^{4} \cdot 3^{7} \)
\( g_1 \)  \(=\) \(-1101463552/9\)
\( g_2 \)  \(=\) \(-156649472/27\)
\( g_3 \)  \(=\) \(-60966976/243\)

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

Rational points

All points: \((1 : 0 : 0),\, (0 : 0 : 1),\, (1 : 1 : 1),\, (1 : -2 : 1),\, (1 : -2 : 2)\)
All points: \((1 : 0 : 0),\, (0 : 0 : 1),\, (1 : 1 : 1),\, (1 : -2 : 1),\, (1 : -2 : 2)\)
All points: \((1 : 0 : 0),\, (0 : 0 : 1),\, (1 : 0 : 2),\, (1 : -3 : 1),\, (1 : 3 : 1)\)

magma: [C![0,0,1],C![1,-2,1],C![1,-2,2],C![1,0,0],C![1,1,1]]; // minimal model
 
magma: [C![0,0,1],C![1,-3,1],C![1,0,2],C![1,0,0],C![1,3,1]]; // simplified model
 

Number of rational Weierstrass points: \(3\)

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: \(\Z/{2}\Z \oplus \Z/{6}\Z\)

magma: MordellWeilGroupGenus2(Jacobian(C));
 

Generator $D_0$ Height Order
\((1 : -2 : 2) - (1 : 0 : 0)\) \(2x - z\) \(=\) \(0,\) \(4y\) \(=\) \(-z^3\) \(0\) \(2\)
\((1 : -2 : 1) - (1 : 0 : 0)\) \(x - z\) \(=\) \(0,\) \(y\) \(=\) \(-2z^3\) \(0\) \(6\)
Generator $D_0$ Height Order
\((1 : -2 : 2) - (1 : 0 : 0)\) \(2x - z\) \(=\) \(0,\) \(4y\) \(=\) \(-z^3\) \(0\) \(2\)
\((1 : -2 : 1) - (1 : 0 : 0)\) \(x - z\) \(=\) \(0,\) \(y\) \(=\) \(-2z^3\) \(0\) \(6\)
Generator $D_0$ Height Order
\(D_0 - 2 \cdot(1 : 0 : 0)\) \(2x - z\) \(=\) \(0,\) \(4y\) \(=\) \(xz^2 - 2z^3\) \(0\) \(2\)
\((1 : -3 : 1) - (1 : 0 : 0)\) \(x - z\) \(=\) \(0,\) \(y\) \(=\) \(xz^2 - 4z^3\) \(0\) \(6\)

2-torsion field: 3.1.243.1

BSD invariants

Hasse-Weil conjecture: unverified
Analytic rank: \(0\)
Mordell-Weil rank: \(0\)
2-Selmer rank:\(2\)
Regulator: \( 1 \)
Real period: \( 11.43628 \)
Tamagawa product: \( 6 \)
Torsion order:\( 12 \)
Leading coefficient: \( 0.476511 \)
Analytic order of Ш: \( 1 \)   (rounded)
Order of Ш:square

Local invariants

Prime ord(\(N\)) ord(\(\Delta\)) Tamagawa L-factor Cluster picture
\(2\) \(3\) \(4\) \(2\) \(1 + T\)
\(3\) \(5\) \(7\) \(3\) \(1 + 3 T^{2}\)

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?
\(2\) 2.120.3 yes
\(3\) 3.1920.4 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);