Genus 2 curve 85403.a.85403.1

• Label: 85403.a.85403.1
• Conductor: $85403$
• Discriminant: $-85403$
• Mordell-Weil group: \(\Z \oplus \Z \oplus \Z\)
• 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

Minimal equation

$y^2 + y = x^6 - x^5 + 2x^3 - x^2 - x$

(, )

Invariants

Conductor:	\( N \)	\(=\)	\(85403\)	\(=\)	\( 41 \cdot 2083 \)
Discriminant:	\( \Delta \)	\(=\)	\(-85403\)	\(=\)	\( - 41 \cdot 2083 \)

Igusa-Clebsch invariants

\( I_2 \)	\(=\)	\(16\)	\(=\)	\( 2^{4} \)
\( I_4 \)	\(=\)	\(-1676\)	\(=\)	\( - 2^{2} \cdot 419 \)
\( I_6 \)	\(=\)	\(-416552\)	\(=\)	\( - 2^{3} \cdot 52069 \)
\( I_{10} \)	\(=\)	\(-341612\)	\(=\)	\( - 2^{2} \cdot 41 \cdot 2083 \)

Automorphism group

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

Rational points

Known points
\((1 : -1 : 0)\)	\((1 : 1 : 0)\)	\((0 : 0 : 1)\)	\((-1 : 0 : 1)\)	\((0 : -1 : 1)\)	\((1 : 0 : 1)\)
\((-1 : -1 : 1)\)	\((1 : -1 : 1)\)	\((-2 : -5 : 3)\)	\((2 : 6 : 1)\)	\((2 : -7 : 1)\)	\((-1 : 16 : 5)\)
\((-2 : -22 : 3)\)	\((-5 : -57 : 8)\)	\((-1 : -141 : 5)\)	\((2 : -377 : 11)\)	\((-5 : -455 : 8)\)	\((2 : -954 : 11)\)

Number of rational Weierstrass points: \(0\)

This curve is locally solvable everywhere.

Mordell-Weil group of the Jacobian

Group structure: \(\Z \oplus \Z \oplus \Z\)

Generator	$D_0$						Height	Order
\((-1 : -1 : 1) - (1 : -1 : 0)\)	\(z (x + z)\)	\(=\)	\(0,\)	\(y\)	\(=\)	\(x^3\)	\(0.516673\)	\(\infty\)
\((-1 : 0 : 1) + (1 : 0 : 1) - (1 : -1 : 0) - (1 : 1 : 0)\)	\((x - z) (x + z)\)	\(=\)	\(0,\)	\(y\)	\(=\)	\(0\)	\(0.328783\)	\(\infty\)
\((-1 : 0 : 1) + (0 : -1 : 1) - (1 : -1 : 0) - (1 : 1 : 0)\)	\(x (x + z)\)	\(=\)	\(0,\)	\(y\)	\(=\)	\(-xz^2 - z^3\)	\(0.329904\)	\(\infty\)

2-torsion field: 6.4.5465792.1

BSD invariants

Hasse-Weil conjecture:	unverified
Analytic rank:	\(3\)   (upper bound)
Mordell-Weil rank:	\(3\)
2-Selmer rank:	\(3\)
Regulator:	\( 0.049862 \)
Real period:	\( 16.94122 \)
Tamagawa product:	\( 1 \)
Torsion order:	\( 1 \)
Leading coefficient:	\( 0.844730 \)
Analytic order of Ш:	\( 1 \)   (rounded)
Order of Ш:	square

Local invariants

Prime	ord(\(N\))	ord(\(\Delta\))	Tamagawa	L-factor	Cluster picture
\(41\)	\(1\)	\(1\)	\(1\)	\(( 1 - T )( 1 + 6 T + 41 T^{2} )\)
\(2083\)	\(1\)	\(1\)	\(1\)	\(( 1 + T )( 1 + 68 T + 2083 T^{2} )\)

Galois representations

The mod-$\ell$ Galois representation has maximal image \(\GSp(4,\F_\ell)\) for all primes \( \ell \) .

Sato-Tate group

\(\mathrm{ST}\)	\(\simeq\)	$\mathrm{USp}(4)$
\(\mathrm{ST}^0\)	\(\simeq\)	\(\mathrm{USp}(4)\)

Decomposition of the Jacobian

Simple over \(\overline{\Q}\)

Endomorphisms of the Jacobian

Not of \(\GL_2\)-type over \(\Q\)

Endomorphism ring over \(\Q\):

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

All \(\overline{\Q}\)-endomorphisms of the Jacobian are defined over \(\Q\).