Properties

Label 2.89.a_agw
Base field $\F_{89}$
Dimension $2$
$p$-rank $0$
Ordinary no
Supersingular yes
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:  $( 1 - 89 x^{2} )^{2}$
  $1 - 178 x^{2} + 7921 x^{4}$
Frobenius angles:  $0$, $0$, $1$, $1$
Angle rank:  $0$ (numerical)
Number field:  \(\Q(\sqrt{89}) \)
Galois group:  $C_2$
Jacobians:  $14$

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

Newton polygon

This isogeny class is supersingular.

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

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $7744$ $59969536$ $496979881024$ $3934601256960000$ $31181719918798064704$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $90$ $7566$ $704970$ $62710558$ $5584059450$ $496978471086$ $44231334895530$ $3936588554733118$ $350356403707485210$ $31181719907629945806$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 14 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 endomorphism algebra of this simple isogeny class is the quaternion algebra over \(\Q(\sqrt{89}) \) ramified at both real infinite places.
Endomorphism algebra over $\overline{\F}_{89}$
The base change of $A$ to $\F_{89^{2}}$ is 1.7921.agw 2 and its endomorphism algebra is $\mathrm{M}_{2}(B)$, where $B$ is the quaternion algebra over \(\Q\) ramified at $89$ and $\infty$.

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.a_dl$3$(not in LMFDB)
2.89.a_gw$4$(not in LMFDB)
2.89.a_dl$6$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.89.a_dl$3$(not in LMFDB)
2.89.a_gw$4$(not in LMFDB)
2.89.a_dl$6$(not in LMFDB)
2.89.a_a$8$(not in LMFDB)
2.89.a_adl$12$(not in LMFDB)