Minimal equation
Minimal equation
Simplified equation
$y^2 + x^2y = x^5 - 2x^4 + 4x^3 - 4x^2 + 3x - 1$ | (homogenize, simplify) |
$y^2 + x^2zy = x^5z - 2x^4z^2 + 4x^3z^3 - 4x^2z^4 + 3xz^5 - z^6$ | (dehomogenize, simplify) |
$y^2 = 4x^5 - 7x^4 + 16x^3 - 16x^2 + 12x - 4$ | (homogenize, minimize) |
sage: R.<x> = PolynomialRing(QQ); C = HyperellipticCurve(R([-1, 3, -4, 4, -2, 1]), R([0, 0, 1]));
magma: R<x> := PolynomialRing(Rationals()); C := HyperellipticCurve(R![-1, 3, -4, 4, -2, 1], R![0, 0, 1]);
sage: X = HyperellipticCurve(R([-4, 12, -16, 16, -7, 4]))
magma: X,pi:= SimplifiedModel(C);
Invariants
Conductor: | \( N \) | \(=\) | \(100325\) | \(=\) | \( 5^{2} \cdot 4013 \) | magma: Conductor(LSeries(C)); Factorization($1);
|
Discriminant: | \( \Delta \) | \(=\) | \(100325\) | \(=\) | \( 5^{2} \cdot 4013 \) | magma: Discriminant(C); Factorization(Integers()!$1);
|
Igusa-Clebsch invariants
Igusa invariants
G2 invariants
\( I_2 \) | \(=\) | \(416\) | \(=\) | \( 2^{5} \cdot 13 \) |
\( I_4 \) | \(=\) | \(4420\) | \(=\) | \( 2^{2} \cdot 5 \cdot 13 \cdot 17 \) |
\( I_6 \) | \(=\) | \(595015\) | \(=\) | \( 5 \cdot 59 \cdot 2017 \) |
\( I_{10} \) | \(=\) | \(401300\) | \(=\) | \( 2^{2} \cdot 5^{2} \cdot 4013 \) |
\( J_2 \) | \(=\) | \(208\) | \(=\) | \( 2^{4} \cdot 13 \) |
\( J_4 \) | \(=\) | \(1066\) | \(=\) | \( 2 \cdot 13 \cdot 41 \) |
\( J_6 \) | \(=\) | \(-2719\) | \(=\) | \( -2719 \) |
\( J_8 \) | \(=\) | \(-425477\) | \(=\) | \( - 13 \cdot 23 \cdot 1423 \) |
\( J_{10} \) | \(=\) | \(100325\) | \(=\) | \( 5^{2} \cdot 4013 \) |
\( g_1 \) | \(=\) | \(389328928768/100325\) | ||
\( g_2 \) | \(=\) | \(9592840192/100325\) | ||
\( g_3 \) | \(=\) | \(-117634816/100325\) |
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: \((1 : 0 : 0),\, (2 : 3 : 1),\, (2 : -7 : 1)\)
magma: [C![1,0,0],C![2,-7,1],C![2,3,1]]; // minimal model
magma: [C![1,0,0],C![2,-10,1],C![2,10,1]]; // 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: \(\Z\)
magma: MordellWeilGroupGenus2(Jacobian(C));
Generator | $D_0$ | Height | Order | |||||
---|---|---|---|---|---|---|---|---|
\(D_0 - 2 \cdot(1 : 0 : 0)\) | \(x^2 - xz + z^2\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(-xz^2 + z^3\) | \(0.396627\) | \(\infty\) |
Generator | $D_0$ | Height | Order | |||||
---|---|---|---|---|---|---|---|---|
\(D_0 - 2 \cdot(1 : 0 : 0)\) | \(x^2 - xz + z^2\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(-xz^2 + z^3\) | \(0.396627\) | \(\infty\) |
Generator | $D_0$ | Height | Order | |||||
---|---|---|---|---|---|---|---|---|
\(D_0 - 2 \cdot(1 : 0 : 0)\) | \(x^2 - xz + z^2\) | \(=\) | \(0,\) | \(y\) | \(=\) | \(x^2z - 2xz^2 + 2z^3\) | \(0.396627\) | \(\infty\) |
2-torsion field: 5.1.1605200.1
BSD invariants
Hasse-Weil conjecture: | unverified |
Analytic rank: | \(1\) |
Mordell-Weil rank: | \(1\) |
2-Selmer rank: | \(1\) |
Regulator: | \( 0.396627 \) |
Real period: | \( 7.575309 \) |
Tamagawa product: | \( 1 \) |
Torsion order: | \( 1 \) |
Leading coefficient: | \( 3.004577 \) |
Analytic order of Ш: | \( 1 \) (rounded) |
Order of Ш: | square |
Local invariants
Prime | ord(\(N\)) | ord(\(\Delta\)) | Tamagawa | L-factor | Cluster picture |
---|---|---|---|---|---|
\(5\) | \(2\) | \(2\) | \(1\) | \(1 + 2 T + 5 T^{2}\) | |
\(4013\) | \(1\) | \(1\) | \(1\) | \(( 1 - T )( 1 + 36 T + 4013 T^{2} )\) |
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);