Properties

Label 168328.a.336656.1
Conductor $168328$
Discriminant $-336656$
Mordell-Weil group \(\Z \oplus \Z \oplus \Z\)
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

$y^2 + (x^3 + x)y = x^5 - x^4 - x^3 + x^2 - 2x + 1$ (homogenize, simplify)
$y^2 + (x^3 + xz^2)y = x^5z - x^4z^2 - x^3z^3 + x^2z^4 - 2xz^5 + z^6$ (dehomogenize, simplify)
$y^2 = x^6 + 4x^5 - 2x^4 - 4x^3 + 5x^2 - 8x + 4$ (homogenize, minimize)

sage: R.<x> = PolynomialRing(QQ); C = HyperellipticCurve(R([1, -2, 1, -1, -1, 1]), R([0, 1, 0, 1]));
 
magma: R<x> := PolynomialRing(Rationals()); C := HyperellipticCurve(R![1, -2, 1, -1, -1, 1], R![0, 1, 0, 1]);
 
sage: X = HyperellipticCurve(R([4, -8, 5, -4, -2, 4, 1]))
 
magma: X,pi:= SimplifiedModel(C);
 

Invariants

Conductor: \( N \)  \(=\)  \(168328\) \(=\) \( 2^{3} \cdot 53 \cdot 397 \)
magma: Conductor(LSeries(C)); Factorization($1);
 
Discriminant: \( \Delta \)  \(=\)  \(-336656\) \(=\) \( - 2^{4} \cdot 53 \cdot 397 \)
magma: Discriminant(C); Factorization(Integers()!$1);
 

Igusa-Clebsch invariants

Igusa invariants

G2 invariants

\( I_2 \)  \(=\) \(496\) \(=\)  \( 2^{4} \cdot 31 \)
\( I_4 \)  \(=\) \(3172\) \(=\)  \( 2^{2} \cdot 13 \cdot 61 \)
\( I_6 \)  \(=\) \(816364\) \(=\)  \( 2^{2} \cdot 409 \cdot 499 \)
\( I_{10} \)  \(=\) \(1346624\) \(=\)  \( 2^{6} \cdot 53 \cdot 397 \)
\( J_2 \)  \(=\) \(248\) \(=\)  \( 2^{3} \cdot 31 \)
\( J_4 \)  \(=\) \(2034\) \(=\)  \( 2 \cdot 3^{2} \cdot 113 \)
\( J_6 \)  \(=\) \(-18980\) \(=\)  \( - 2^{2} \cdot 5 \cdot 13 \cdot 73 \)
\( J_8 \)  \(=\) \(-2211049\) \(=\)  \( - 19 \cdot 116371 \)
\( J_{10} \)  \(=\) \(336656\) \(=\)  \( 2^{4} \cdot 53 \cdot 397 \)
\( g_1 \)  \(=\) \(58632501248/21041\)
\( g_2 \)  \(=\) \(1939036608/21041\)
\( g_3 \)  \(=\) \(-72959120/21041\)

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

Known points
\((1 : 0 : 0)\) \((1 : -1 : 0)\) \((0 : -1 : 1)\) \((0 : 1 : 1)\) \((-1 : -1 : 1)\) \((1 : -1 : 1)\)
\((1 : 1 : 2)\) \((-1 : 3 : 1)\) \((3 : -1 : 2)\) \((1 : -6 : 2)\) \((3 : -38 : 2)\) \((-5 : 57 : 3)\)
\((-8 : 83 : 1)\) \((-5 : 113 : 3)\) \((-8 : 437 : 1)\)
Known points
\((1 : 0 : 0)\) \((1 : -1 : 0)\) \((0 : -1 : 1)\) \((0 : 1 : 1)\) \((-1 : -1 : 1)\) \((1 : -1 : 1)\)
\((1 : 1 : 2)\) \((-1 : 3 : 1)\) \((3 : -1 : 2)\) \((1 : -6 : 2)\) \((3 : -38 : 2)\) \((-5 : 57 : 3)\)
\((-8 : 83 : 1)\) \((-5 : 113 : 3)\) \((-8 : 437 : 1)\)
Known points
\((1 : -1 : 0)\) \((1 : 1 : 0)\) \((1 : 0 : 1)\) \((0 : -2 : 1)\) \((0 : 2 : 1)\) \((-1 : -4 : 1)\)
\((-1 : 4 : 1)\) \((1 : -7 : 2)\) \((1 : 7 : 2)\) \((3 : -37 : 2)\) \((3 : 37 : 2)\) \((-5 : -56 : 3)\)
\((-5 : 56 : 3)\) \((-8 : -354 : 1)\) \((-8 : 354 : 1)\)

magma: [C![-8,83,1],C![-8,437,1],C![-5,57,3],C![-5,113,3],C![-1,-1,1],C![-1,3,1],C![0,-1,1],C![0,1,1],C![1,-6,2],C![1,-1,0],C![1,-1,1],C![1,0,0],C![1,1,2],C![3,-38,2],C![3,-1,2]]; // minimal model
 
magma: [C![-8,-354,1],C![-8,354,1],C![-5,-56,3],C![-5,56,3],C![-1,-4,1],C![-1,4,1],C![0,-2,1],C![0,2,1],C![1,-7,2],C![1,-1,0],C![1,0,1],C![1,1,0],C![1,7,2],C![3,-37,2],C![3,37,2]]; // simplified model
 

Number of rational Weierstrass points: \(1\)

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: \(\Z \oplus \Z \oplus \Z\)

magma: MordellWeilGroupGenus2(Jacobian(C));
 

Generator $D_0$ Height Order
\(D_0 - (1 : -1 : 0) - (1 : 0 : 0)\) \(x^2 + xz - z^2\) \(=\) \(0,\) \(y\) \(=\) \(-2xz^2 + z^3\) \(0.639768\) \(\infty\)
\((0 : -1 : 1) + (1 : -1 : 1) - (1 : -1 : 0) - (1 : 0 : 0)\) \(x (x - z)\) \(=\) \(0,\) \(y\) \(=\) \(-z^3\) \(0.553094\) \(\infty\)
\((1 : -1 : 1) - (1 : -1 : 0)\) \(z (x - z)\) \(=\) \(0,\) \(y\) \(=\) \(-z^3\) \(0.159908\) \(\infty\)
Generator $D_0$ Height Order
\(D_0 - (1 : -1 : 0) - (1 : 0 : 0)\) \(x^2 + xz - z^2\) \(=\) \(0,\) \(y\) \(=\) \(-2xz^2 + z^3\) \(0.639768\) \(\infty\)
\((0 : -1 : 1) + (1 : -1 : 1) - (1 : -1 : 0) - (1 : 0 : 0)\) \(x (x - z)\) \(=\) \(0,\) \(y\) \(=\) \(-z^3\) \(0.553094\) \(\infty\)
\((1 : -1 : 1) - (1 : -1 : 0)\) \(z (x - z)\) \(=\) \(0,\) \(y\) \(=\) \(-z^3\) \(0.159908\) \(\infty\)
Generator $D_0$ Height Order
\(D_0 - (1 : -1 : 0) - (1 : 1 : 0)\) \(x^2 + xz - z^2\) \(=\) \(0,\) \(y\) \(=\) \(x^3 - 3xz^2 + 2z^3\) \(0.639768\) \(\infty\)
\((0 : -2 : 1) + (1 : 0 : 1) - (1 : -1 : 0) - (1 : 1 : 0)\) \(x (x - z)\) \(=\) \(0,\) \(y\) \(=\) \(x^3 + xz^2 - 2z^3\) \(0.553094\) \(\infty\)
\((1 : 0 : 1) - (1 : -1 : 0)\) \(z (x - z)\) \(=\) \(0,\) \(y\) \(=\) \(x^3 + xz^2 - 2z^3\) \(0.159908\) \(\infty\)

2-torsion field: 5.3.84164.1

BSD invariants

Hasse-Weil conjecture: unverified
Analytic rank: \(3\)   (upper bound)
Mordell-Weil rank: \(3\)
2-Selmer rank:\(3\)
Regulator: \( 0.046316 \)
Real period: \( 15.56270 \)
Tamagawa product: \( 2 \)
Torsion order:\( 1 \)
Leading coefficient: \( 1.441610 \)
Analytic order of Ш: \( 1 \)   (rounded)
Order of Ш:square

Local invariants

Prime ord(\(N\)) ord(\(\Delta\)) Tamagawa L-factor Cluster picture
\(2\) \(3\) \(4\) \(2\) \(1 + T + 2 T^{2}\)
\(53\) \(1\) \(1\) \(1\) \(( 1 + T )( 1 - 4 T + 53 T^{2} )\)
\(397\) \(1\) \(1\) \(1\) \(( 1 + T )( 1 + 24 T + 397 T^{2} )\)

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?
\(2\) 2.6.1 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);