Properties

Label 2.89.c_gx
Base field $\F_{89}$
Dimension $2$
$p$-rank $2$
Ordinary yes
Supersingular no
Simple no
Geometrically simple no
Primitive yes
Principally polarizable yes
Contains a Jacobian yes

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Invariants

Base field:  $\F_{89}$
Dimension:  $2$
L-polynomial:  $( 1 + x + 89 x^{2} )^{2}$
  $1 + 2 x + 179 x^{2} + 178 x^{3} + 7921 x^{4}$
Frobenius angles:  $\pm0.516878298350$, $\pm0.516878298350$
Angle rank:  $1$ (numerical)
Jacobians:  $66$

This isogeny class is not simple, primitive, ordinary, and not supersingular. It is principally polarizable and contains a Jacobian.

Newton polygon

This isogeny class is ordinary.

$p$-rank:  $2$
Slopes:  $[0, 0, 1, 1]$

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $8281$ $65593801$ $496607727616$ $3934645792830025$ $31182157297372129321$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $92$ $8276$ $704438$ $62711268$ $5584137772$ $496983969326$ $44231325246508$ $3936588576976708$ $350356404794973542$ $31181719949235253556$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 66 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{89}$.

Endomorphism algebra over $\F_{89}$
The isogeny class factors as 1.89.b 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-355}) \)$)$

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.89.ac_gx$2$(not in LMFDB)
2.89.a_gv$2$(not in LMFDB)
2.89.ab_adk$3$(not in LMFDB)

Below is a list of all twists of this isogeny class.

TwistExtension degreeCommon base change
2.89.ac_gx$2$(not in LMFDB)
2.89.a_gv$2$(not in LMFDB)
2.89.ab_adk$3$(not in LMFDB)
2.89.a_agv$4$(not in LMFDB)
2.89.b_adk$6$(not in LMFDB)