Genus 2 curve 12500.a.12500.1

• Label: 12500.a.12500.1
• Conductor: $12500$
• Discriminant: $12500$
• Mordell-Weil group: \(\Z/{5}\Z\)
• 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

Minimal equation

$y^2 + (x^3 + 1)y = x^6 + 2x^3 - x$

(, )

Invariants

Conductor:	\( N \)	\(=\)	\(12500\)	\(=\)	\( 2^{2} \cdot 5^{5} \)
Discriminant:	\( \Delta \)	\(=\)	\(12500\)	\(=\)	\( 2^{2} \cdot 5^{5} \)

Igusa-Clebsch invariants

\( I_2 \)	\(=\)	\(60\)	\(=\)	\( 2^{2} \cdot 3 \cdot 5 \)
\( I_4 \)	\(=\)	\(2025\)	\(=\)	\( 3^{4} \cdot 5^{2} \)
\( I_6 \)	\(=\)	\(67995\)	\(=\)	\( 3^{2} \cdot 5 \cdot 1511 \)
\( I_{10} \)	\(=\)	\(-512\)	\(=\)	\( - 2^{9} \)

Automorphism group

\(\mathrm{Aut}(X)\)	\(\simeq\)	$C_2$
\(\mathrm{Aut}(X_{\overline{\Q}})\)	\(\simeq\)	$C_2$

Rational points

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

Number of rational Weierstrass points: \(1\)

This curve is locally solvable everywhere.

Mordell-Weil group of the Jacobian

Group structure: \(\Z/{5}\Z\)

Generator	$D_0$						Height	Order
\((-1 : 0 : 1) + (0 : 0 : 1) - D_\infty\)	\(x (x + z)\)	\(=\)	\(0,\)	\(y\)	\(=\)	\(0\)	\(0\)	\(5\)

2-torsion field: 5.1.200000.1

BSD invariants

Hasse-Weil conjecture:	unverified
Analytic rank:	\(0\)
Mordell-Weil rank:	\(0\)
2-Selmer rank:	\(0\)
Regulator:	\( 1 \)
Real period:	\( 25.01138 \)
Tamagawa product:	\( 1 \)
Torsion order:	\( 5 \)
Leading coefficient:	\( 1.000455 \)
Analytic order of Ш:	\( 1 \)   (rounded)
Order of Ш:	square

Local invariants

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

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?
\(2\)	2.36.1	no
\(3\)	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 \(\overline{\Q}\)

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 \(K = \Q (a) \simeq \) \(\Q(\sqrt{5}) \) with defining polynomial \(x^{2} - x - 1\)

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

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

\(\End (J_{\overline{\Q}})\)	\(\simeq\)	\(\Z [\frac{1 + \sqrt{5}}{2}]\)
\(\End (J_{\overline{\Q}}) \otimes \Q \)	\(\simeq\)	\(\Q(\sqrt{5}) \)
\(\End (J_{\overline{\Q}}) \otimes \R\)	\(\simeq\)	\(\R \times \R\)