Properties

Label 36864.c.36864.1
Conductor $36864$
Discriminant $36864$
Mordell-Weil group \(\Z \oplus \Z/{2}\Z\)
Sato-Tate group $N(\mathrm{SU}(2)\times\mathrm{SU}(2))$
\(\End(J_{\overline{\Q}}) \otimes \R\) \(\R \times \R\)
\(\End(J_{\overline{\Q}}) \otimes \Q\) \(\mathsf{RM}\)
\(\End(J) \otimes \Q\) \(\Q\)
\(\overline{\Q}\)-simple yes
\(\mathrm{GL}_2\)-type no

Related objects

Downloads

Learn more

Show commands: Magma / SageMath

Minimal equation

Minimal equation

Simplified equation

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

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

Invariants

Conductor: \( N \)  \(=\)  \(36864\) \(=\) \( 2^{12} \cdot 3^{2} \)
magma: Conductor(LSeries(C: ExcFactors:=[*<2,Valuation(36864,2),R![1]>*])); Factorization($1);
 
Discriminant: \( \Delta \)  \(=\)  \(36864\) \(=\) \( 2^{12} \cdot 3^{2} \)
magma: Discriminant(C); Factorization(Integers()!$1);
 

Igusa-Clebsch invariants

Igusa invariants

G2 invariants

\( I_2 \)  \(=\) \(62\) \(=\)  \( 2 \cdot 31 \)
\( I_4 \)  \(=\) \(-92\) \(=\)  \( - 2^{2} \cdot 23 \)
\( I_6 \)  \(=\) \(-2096\) \(=\)  \( - 2^{4} \cdot 131 \)
\( I_{10} \)  \(=\) \(144\) \(=\)  \( 2^{4} \cdot 3^{2} \)
\( J_2 \)  \(=\) \(124\) \(=\)  \( 2^{2} \cdot 31 \)
\( J_4 \)  \(=\) \(886\) \(=\)  \( 2 \cdot 443 \)
\( J_6 \)  \(=\) \(10868\) \(=\)  \( 2^{2} \cdot 11 \cdot 13 \cdot 19 \)
\( J_8 \)  \(=\) \(140659\) \(=\)  \( 140659 \)
\( J_{10} \)  \(=\) \(36864\) \(=\)  \( 2^{12} \cdot 3^{2} \)
\( g_1 \)  \(=\) \(28629151/36\)
\( g_2 \)  \(=\) \(13197413/288\)
\( g_3 \)  \(=\) \(2611037/576\)

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

magma: [C![-1,0,1],C![0,-1,1],C![0,1,1],C![1,0,0]]; // minimal model
 
magma: [C![-1,0,1],C![0,-1/2,1],C![0,1/2,1],C![1,0,0]]; // 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: \(\Z \oplus \Z/{2}\Z\)

magma: MordellWeilGroupGenus2(Jacobian(C));
 

Generator $D_0$ Height Order
\((0 : -1 : 1) - (1 : 0 : 0)\) \(x\) \(=\) \(0,\) \(y\) \(=\) \(-z^3\) \(0.506281\) \(\infty\)
\((-1 : 0 : 1) - (1 : 0 : 0)\) \(x + z\) \(=\) \(0,\) \(y\) \(=\) \(0\) \(0\) \(2\)
Generator $D_0$ Height Order
\((0 : -1 : 1) - (1 : 0 : 0)\) \(x\) \(=\) \(0,\) \(y\) \(=\) \(-z^3\) \(0.506281\) \(\infty\)
\((-1 : 0 : 1) - (1 : 0 : 0)\) \(x + z\) \(=\) \(0,\) \(y\) \(=\) \(0\) \(0\) \(2\)
Generator $D_0$ Height Order
\((0 : -1/2 : 1) - (1 : 0 : 0)\) \(x\) \(=\) \(0,\) \(y\) \(=\) \(-1/2z^3\) \(0.506281\) \(\infty\)
\((-1 : 0 : 1) - (1 : 0 : 0)\) \(x + z\) \(=\) \(0,\) \(y\) \(=\) \(0\) \(0\) \(2\)

2-torsion field: \(\Q(\zeta_{12})\)

BSD invariants

Hasse-Weil conjecture: unverified
Analytic rank: \(1\)
Mordell-Weil rank: \(1\)
2-Selmer rank:\(2\)
Regulator: \( 0.506281 \)
Real period: \( 13.55119 \)
Tamagawa product: \( 1 \)
Torsion order:\( 2 \)
Leading coefficient: \( 1.715179 \)
Analytic order of Ш: \( 1 \)   (rounded)
Order of Ш:square

Local invariants

Prime ord(\(N\)) ord(\(\Delta\)) Tamagawa L-factor Cluster picture
\(2\) \(12\) \(12\) \(1\) \(1\)
\(3\) \(2\) \(2\) \(1\) \(1 + T^{2}\)

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?
\(2\) 2.180.5 yes
\(3\) 3.36.1 no

Sato-Tate group

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

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 \(\Q\):

\(\End (J_{})\)\(\simeq\)\(\Z\)
\(\End (J_{}) \otimes \Q \)\(\simeq\)\(\Q\)
\(\End (J_{}) \otimes \R\)\(\simeq\) \(\R\)

Smallest field over which all endomorphisms are defined:
Galois number field \(K = \Q (a) \simeq \) \(\Q(\sqrt{2}) \) with defining polynomial \(x^{2} - 2\)

Of \(\GL_2\)-type over \(\overline{\Q}\)

Endomorphism ring over \(\overline{\Q}\):

\(\End (J_{\overline{\Q}})\)\(\simeq\)\(\Z [\sqrt{2}]\)
\(\End (J_{\overline{\Q}}) \otimes \Q \)\(\simeq\)\(\Q(\sqrt{2}) \)
\(\End (J_{\overline{\Q}}) \otimes \R\)\(\simeq\) \(\R \times \R\)

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);