Properties

Label 2.89.a_gg
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:  $( 1 - 4 x + 89 x^{2} )( 1 + 4 x + 89 x^{2} )$
  $1 + 162 x^{2} + 7921 x^{4}$
Frobenius angles:  $\pm0.432002453901$, $\pm0.567997546099$
Angle rank:  $1$ (numerical)
Jacobians:  $112$
Cyclic group of points:    no
Non-cyclic primes:   $2$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $8084$ $65351056$ $496981692884$ $3935283749785600$ $31181719923982733204$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $90$ $8246$ $704970$ $62721438$ $5584059450$ $496982094806$ $44231334895530$ $3936588840267838$ $350356403707485210$ $31181719917999282806$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 112 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{89^{2}}$.

Endomorphism algebra over $\F_{89}$
The isogeny class factors as 1.89.ae $\times$ 1.89.e and its endomorphism algebra is a direct product of the endomorphism algebras for each isotypic factor. The endomorphism algebra for each factor is:
Endomorphism algebra over $\overline{\F}_{89}$
The base change of $A$ to $\F_{89^{2}}$ is 1.7921.gg 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-85}) \)$)$

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.ai_hm$2$(not in LMFDB)
2.89.i_hm$2$(not in LMFDB)
2.89.a_agg$4$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.89.ai_hm$2$(not in LMFDB)
2.89.i_hm$2$(not in LMFDB)
2.89.a_agg$4$(not in LMFDB)
2.89.ae_acv$6$(not in LMFDB)
2.89.e_acv$6$(not in LMFDB)