Properties

Label 2859.a.77193.1
Conductor $2859$
Discriminant $-77193$
Mordell-Weil group \(\Z \oplus \Z/{3}\Z\)
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

Related objects

Downloads

Learn more

Show commands: Magma / SageMath

Minimal equation

Minimal equation

Simplified equation

$y^2 + (x^3 + x + 1)y = 2x^5 + 4x^4 + x^3 + 2x^2$ (homogenize, simplify)
$y^2 + (x^3 + xz^2 + z^3)y = 2x^5z + 4x^4z^2 + x^3z^3 + 2x^2z^4$ (dehomogenize, simplify)
$y^2 = x^6 + 8x^5 + 18x^4 + 6x^3 + 9x^2 + 2x + 1$ (homogenize, minimize)

sage: R.<x> = PolynomialRing(QQ); C = HyperellipticCurve(R([0, 0, 2, 1, 4, 2]), R([1, 1, 0, 1]));
 
magma: R<x> := PolynomialRing(Rationals()); C := HyperellipticCurve(R![0, 0, 2, 1, 4, 2], R![1, 1, 0, 1]);
 
sage: X = HyperellipticCurve(R([1, 2, 9, 6, 18, 8, 1]))
 
magma: X,pi:= SimplifiedModel(C);
 

Invariants

Conductor: \( N \)  \(=\)  \(2859\) \(=\) \( 3 \cdot 953 \)
magma: Conductor(LSeries(C)); Factorization($1);
 
Discriminant: \( \Delta \)  \(=\)  \(-77193\) \(=\) \( - 3^{4} \cdot 953 \)
magma: Discriminant(C); Factorization(Integers()!$1);
 

Igusa-Clebsch invariants

Igusa invariants

G2 invariants

\( I_2 \)  \(=\) \(988\) \(=\)  \( 2^{2} \cdot 13 \cdot 19 \)
\( I_4 \)  \(=\) \(69913\) \(=\)  \( 151 \cdot 463 \)
\( I_6 \)  \(=\) \(17187731\) \(=\)  \( 11 \cdot 17 \cdot 107 \cdot 859 \)
\( I_{10} \)  \(=\) \(9880704\) \(=\)  \( 2^{7} \cdot 3^{4} \cdot 953 \)
\( J_2 \)  \(=\) \(247\) \(=\)  \( 13 \cdot 19 \)
\( J_4 \)  \(=\) \(-371\) \(=\)  \( - 7 \cdot 53 \)
\( J_6 \)  \(=\) \(-3969\) \(=\)  \( - 3^{4} \cdot 7^{2} \)
\( J_8 \)  \(=\) \(-279496\) \(=\)  \( - 2^{3} \cdot 7^{2} \cdot 23 \cdot 31 \)
\( J_{10} \)  \(=\) \(77193\) \(=\)  \( 3^{4} \cdot 953 \)
\( g_1 \)  \(=\) \(919358226007/77193\)
\( g_2 \)  \(=\) \(-5590681733/77193\)
\( g_3 \)  \(=\) \(-2989441/953\)

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
\((1 : 0 : 0)\) \((1 : -1 : 0)\) \((0 : 0 : 1)\) \((0 : -1 : 1)\) \((-2 : 0 : 1)\) \((-2 : 9 : 1)\)
\((-1 : 9 : 4)\) \((-1 : -56 : 4)\)
All points
\((1 : 0 : 0)\) \((1 : -1 : 0)\) \((0 : 0 : 1)\) \((0 : -1 : 1)\) \((-2 : 0 : 1)\) \((-2 : 9 : 1)\)
\((-1 : 9 : 4)\) \((-1 : -56 : 4)\)
All points
\((1 : -1 : 0)\) \((1 : 1 : 0)\) \((0 : -1 : 1)\) \((0 : 1 : 1)\) \((-2 : -9 : 1)\) \((-2 : 9 : 1)\)
\((-1 : -65 : 4)\) \((-1 : 65 : 4)\)

magma: [C![-2,0,1],C![-2,9,1],C![-1,-56,4],C![-1,9,4],C![0,-1,1],C![0,0,1],C![1,-1,0],C![1,0,0]]; // minimal model
 
magma: [C![-2,-9,1],C![-2,9,1],C![-1,-65,4],C![-1,65,4],C![0,-1,1],C![0,1,1],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: \(\Z \oplus \Z/{3}\Z\)

magma: MordellWeilGroupGenus2(Jacobian(C));
 

Generator $D_0$ Height Order
\(D_0 - (1 : -1 : 0) - (1 : 0 : 0)\) \(2x^2 + z^2\) \(=\) \(0,\) \(y\) \(=\) \(0\) \(0.115761\) \(\infty\)
\((0 : 0 : 1) - (1 : -1 : 0)\) \(z x\) \(=\) \(0,\) \(y\) \(=\) \(0\) \(0\) \(3\)
Generator $D_0$ Height Order
\(D_0 - (1 : -1 : 0) - (1 : 0 : 0)\) \(2x^2 + z^2\) \(=\) \(0,\) \(y\) \(=\) \(0\) \(0.115761\) \(\infty\)
\((0 : 0 : 1) - (1 : -1 : 0)\) \(z x\) \(=\) \(0,\) \(y\) \(=\) \(0\) \(0\) \(3\)
Generator $D_0$ Height Order
\(D_0 - (1 : -1 : 0) - (1 : 1 : 0)\) \(2x^2 + z^2\) \(=\) \(0,\) \(y\) \(=\) \(x^3 + xz^2 + z^3\) \(0.115761\) \(\infty\)
\((0 : 1 : 1) - (1 : -1 : 0)\) \(z x\) \(=\) \(0,\) \(y\) \(=\) \(x^3 + xz^2 + z^3\) \(0\) \(3\)

2-torsion field: 6.0.60992.1

BSD invariants

Hasse-Weil conjecture: unverified
Analytic rank: \(1\)
Mordell-Weil rank: \(1\)
2-Selmer rank:\(1\)
Regulator: \( 0.115761 \)
Real period: \( 14.60847 \)
Tamagawa product: \( 2 \)
Torsion order:\( 3 \)
Leading coefficient: \( 0.375801 \)
Analytic order of Ш: \( 1 \)   (rounded)
Order of Ш:square

Local invariants

Prime ord(\(N\)) ord(\(\Delta\)) Tamagawa L-factor Cluster picture
\(3\) \(1\) \(4\) \(2\) \(( 1 + T )( 1 + 2 T + 3 T^{2} )\)
\(953\) \(1\) \(1\) \(1\) \(( 1 - T )( 1 + 42 T + 953 T^{2} )\)

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?
\(2\) 2.10.1 no
\(3\) 3.80.1 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);