Properties

Label 2.89.p_fg
Base field $\F_{89}$
Dimension $2$
$p$-rank $2$
Ordinary yes
Supersingular no
Simple yes
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:  $1 + 15 x + 136 x^{2} + 1335 x^{3} + 7921 x^{4}$
Frobenius angles:  $\pm0.459195030373$, $\pm0.874138302960$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(\sqrt{-3}, \sqrt{-131})\)
Galois group:  $C_2^2$
Jacobians:  $465$
Cyclic group of points:    no
Non-cyclic primes:   $2$

This isogeny class is simple but not geometrically 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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $9408$ $63108864$ $497871360000$ $3935733563833344$ $31180891132388238528$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $105$ $7969$ $706230$ $62728609$ $5583911025$ $496983317038$ $44231332909785$ $3936588866076289$ $350356401542796390$ $31181719940828045329$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 465 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{89^{3}}$.

Endomorphism algebra over $\F_{89}$
The endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{-3}, \sqrt{-131})\).
Endomorphism algebra over $\overline{\F}_{89}$
The base change of $A$ to $\F_{89^{3}}$ is 1.704969.yg 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-131}) \)$)$

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.ap_fg$2$(not in LMFDB)
2.89.abe_pn$3$(not in LMFDB)
2.89.a_abv$6$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.89.ap_fg$2$(not in LMFDB)
2.89.abe_pn$3$(not in LMFDB)
2.89.a_abv$6$(not in LMFDB)
2.89.be_pn$6$(not in LMFDB)
2.89.a_bv$12$(not in LMFDB)