Properties

Label 2.23.ae_by
Base field $\F_{23}$
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:  $\F_{23}$
Dimension:  $2$
L-polynomial:  $( 1 - 2 x + 23 x^{2} )^{2}$
  $1 - 4 x + 50 x^{2} - 92 x^{3} + 529 x^{4}$
Frobenius angles:  $\pm0.433137181604$, $\pm0.433137181604$
Angle rank:  $1$ (numerical)
Jacobians:  $8$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $484$ $327184$ $151240804$ $77916906496$ $41369877891364$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $20$ $614$ $12428$ $278430$ $6427540$ $148050758$ $3405057676$ $78311107774$ $1801147565204$ $41426498203814$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 8 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{23}$.

Endomorphism algebra over $\F_{23}$
The isogeny class factors as 1.23.ac 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-22}) \)$)$

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.23.a_bq$2$(not in LMFDB)
2.23.e_by$2$(not in LMFDB)
2.23.c_at$3$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.23.a_bq$2$(not in LMFDB)
2.23.e_by$2$(not in LMFDB)
2.23.c_at$3$(not in LMFDB)
2.23.a_abq$4$(not in LMFDB)
2.23.ac_at$6$(not in LMFDB)