Properties

Label 2.89.b_adk
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:  $1 + x - 88 x^{2} + 89 x^{3} + 7921 x^{4}$
Frobenius angles:  $\pm0.183544965017$, $\pm0.850211631683$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(\sqrt{-3}, \sqrt{-355})\)
Galois group:  $C_2^2$
Jacobians:  $132$
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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $7924$ $61363456$ $497357815696$ $3937560671908864$ $31181938603267829524$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $91$ $7745$ $705502$ $62757729$ $5584098611$ $496983969326$ $44231330071019$ $3936588920064769$ $350356402619996878$ $31181719920331648625$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 132 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 \(\Q(\sqrt{-3}, \sqrt{-355})\).
Endomorphism algebra over $\overline{\F}_{89}$
The base change of $A$ to $\F_{89^{3}}$ is 1.704969.kg 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.ab_adk$2$(not in LMFDB)
2.89.ac_gx$3$(not in LMFDB)
2.89.a_gv$6$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.89.ab_adk$2$(not in LMFDB)
2.89.ac_gx$3$(not in LMFDB)
2.89.a_gv$6$(not in LMFDB)
2.89.c_gx$6$(not in LMFDB)
2.89.a_agv$12$(not in LMFDB)