Properties

Label 15360.h.184320.1
Conductor $15360$
Discriminant $184320$
Mordell-Weil group \(\Z \oplus \Z/{2}\Z \oplus \Z/{2}\Z \oplus \Z/{2}\Z\)
Sato-Tate group $N(\mathrm{U}(1)\times\mathrm{SU}(2))$
\(\End(J_{\overline{\Q}}) \otimes \R\) \(\C \times \R\)
\(\End(J_{\overline{\Q}}) \otimes \Q\) \(\mathsf{CM} \times \Q\)
\(\End(J) \otimes \Q\) \(\Q \times \Q\)
\(\overline{\Q}\)-simple no
\(\mathrm{GL}_2\)-type yes

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Minimal equation

Minimal equation

Simplified equation

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

sage: R.<x> = PolynomialRing(QQ); C = HyperellipticCurve(R([1, 3, 0, -5, -1, 2]), R([]));
 
magma: R<x> := PolynomialRing(Rationals()); C := HyperellipticCurve(R![1, 3, 0, -5, -1, 2], R![]);
 
sage: X = HyperellipticCurve(R([1, 3, 0, -5, -1, 2]))
 
magma: X,pi:= SimplifiedModel(C);
 

Invariants

Conductor: \( N \)  \(=\)  \(15360\) \(=\) \( 2^{10} \cdot 3 \cdot 5 \)
magma: Conductor(LSeries(C: ExcFactors:=[*<2,Valuation(15360,2),R![1]>*])); Factorization($1);
 
Discriminant: \( \Delta \)  \(=\)  \(184320\) \(=\) \( 2^{12} \cdot 3^{2} \cdot 5 \)
magma: Discriminant(C); Factorization(Integers()!$1);
 

Igusa-Clebsch invariants

Igusa invariants

G2 invariants

\( I_2 \)  \(=\) \(390\) \(=\)  \( 2 \cdot 3 \cdot 5 \cdot 13 \)
\( I_4 \)  \(=\) \(852\) \(=\)  \( 2^{2} \cdot 3 \cdot 71 \)
\( I_6 \)  \(=\) \(105720\) \(=\)  \( 2^{3} \cdot 3 \cdot 5 \cdot 881 \)
\( I_{10} \)  \(=\) \(720\) \(=\)  \( 2^{4} \cdot 3^{2} \cdot 5 \)
\( J_2 \)  \(=\) \(780\) \(=\)  \( 2^{2} \cdot 3 \cdot 5 \cdot 13 \)
\( J_4 \)  \(=\) \(23078\) \(=\)  \( 2 \cdot 11 \cdot 1049 \)
\( J_6 \)  \(=\) \(838980\) \(=\)  \( 2^{2} \cdot 3^{2} \cdot 5 \cdot 59 \cdot 79 \)
\( J_8 \)  \(=\) \(30452579\) \(=\)  \( 30452579 \)
\( J_{10} \)  \(=\) \(184320\) \(=\)  \( 2^{12} \cdot 3^{2} \cdot 5 \)
\( g_1 \)  \(=\) \(6265569375/4\)
\( g_2 \)  \(=\) \(1901338725/32\)
\( g_3 \)  \(=\) \(177234525/64\)

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

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

Number of rational Weierstrass points: \(4\)

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

magma: MordellWeilGroupGenus2(Jacobian(C));
 

Generator $D_0$ Height Order
\((0 : -1 : 1) - (1 : 0 : 0)\) \(x\) \(=\) \(0,\) \(y\) \(=\) \(-z^3\) \(0.516278\) \(\infty\)
\((1 : 0 : 1) - (1 : 0 : 0)\) \(x - z\) \(=\) \(0,\) \(y\) \(=\) \(0\) \(0\) \(2\)
\((-1 : 0 : 1) + (1 : 0 : 1) - 2 \cdot(1 : 0 : 0)\) \((x - z) (x + z)\) \(=\) \(0,\) \(y\) \(=\) \(0\) \(0\) \(2\)
\((-1 : 0 : 1) + (-1 : 0 : 2) - 2 \cdot(1 : 0 : 0)\) \((x + z) (2x + z)\) \(=\) \(0,\) \(y\) \(=\) \(0\) \(0\) \(2\)
Generator $D_0$ Height Order
\((0 : -1 : 1) - (1 : 0 : 0)\) \(x\) \(=\) \(0,\) \(y\) \(=\) \(-z^3\) \(0.516278\) \(\infty\)
\((1 : 0 : 1) - (1 : 0 : 0)\) \(x - z\) \(=\) \(0,\) \(y\) \(=\) \(0\) \(0\) \(2\)
\((-1 : 0 : 1) + (1 : 0 : 1) - 2 \cdot(1 : 0 : 0)\) \((x - z) (x + z)\) \(=\) \(0,\) \(y\) \(=\) \(0\) \(0\) \(2\)
\((-1 : 0 : 1) + (-1 : 0 : 2) - 2 \cdot(1 : 0 : 0)\) \((x + z) (2x + z)\) \(=\) \(0,\) \(y\) \(=\) \(0\) \(0\) \(2\)
Generator $D_0$ Height Order
\((0 : -1/2 : 1) - (1 : 0 : 0)\) \(x\) \(=\) \(0,\) \(y\) \(=\) \(-1/2z^3\) \(0.516278\) \(\infty\)
\((1 : 0 : 1) - (1 : 0 : 0)\) \(x - z\) \(=\) \(0,\) \(y\) \(=\) \(0\) \(0\) \(2\)
\((-1 : 0 : 1) + (1 : 0 : 1) - 2 \cdot(1 : 0 : 0)\) \((x - z) (x + z)\) \(=\) \(0,\) \(y\) \(=\) \(0\) \(0\) \(2\)
\((-1 : 0 : 1) + (-1 : 0 : 2) - 2 \cdot(1 : 0 : 0)\) \((x + z) (2x + z)\) \(=\) \(0,\) \(y\) \(=\) \(0\) \(0\) \(2\)

2-torsion field: \(\Q(\sqrt{5}) \)

BSD invariants

Hasse-Weil conjecture: verified
Analytic rank: \(1\)
Mordell-Weil rank: \(1\)
2-Selmer rank:\(4\)
Regulator: \( 0.516278 \)
Real period: \( 17.10135 \)
Tamagawa product: \( 8 \)
Torsion order:\( 8 \)
Leading coefficient: \( 1.103632 \)
Analytic order of Ш: \( 1 \)   (rounded)
Order of Ш:square

Local invariants

Prime ord(\(N\)) ord(\(\Delta\)) Tamagawa L-factor Cluster picture
\(2\) \(10\) \(12\) \(4\) \(1\)
\(3\) \(1\) \(2\) \(2\) \(( 1 + T )( 1 + 3 T^{2} )\)
\(5\) \(1\) \(1\) \(1\) \(( 1 - T )( 1 + 2 T + 5 T^{2} )\)

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?
\(2\) 2.360.2 yes
\(3\) 3.270.2 no

Sato-Tate group

\(\mathrm{ST}\)\(\simeq\) $N(\mathrm{U}(1)\times\mathrm{SU}(2))$
\(\mathrm{ST}^0\)\(\simeq\) \(\mathrm{U}(1)\times\mathrm{SU}(2)\)

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 480.c
  Elliptic curve isogeny class 32.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 \(\Z \times \Z\)
\(\End (J_{}) \otimes \Q \)\(\simeq\)\(\Q\) \(\times\) \(\Q\)
\(\End (J_{}) \otimes \R\)\(\simeq\) \(\R \times \R\)

Smallest field over which all endomorphisms are defined:
Galois number field \(K = \Q (a) \simeq \) \(\Q(\sqrt{-1}) \) with defining polynomial \(x^{2} + 1\)

Not of \(\GL_2\)-type over \(\overline{\Q}\)

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

\(\End (J_{\overline{\Q}})\)\(\simeq\)an order of index \(4\) in \(\Z \times \Z [\sqrt{-1}]\)
\(\End (J_{\overline{\Q}}) \otimes \Q \)\(\simeq\)\(\Q\) \(\times\) \(\Q(\sqrt{-1}) \)
\(\End (J_{\overline{\Q}}) \otimes \R\)\(\simeq\) \(\R \times \C\)

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);