Properties

Label 2.23.g_cd
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:  $( 1 + 3 x + 23 x^{2} )^{2}$
  $1 + 6 x + 55 x^{2} + 138 x^{3} + 529 x^{4}$
Frobenius angles:  $\pm0.601257449372$, $\pm0.601257449372$
Angle rank:  $1$ (numerical)
Jacobians:  $15$
Cyclic group of points:    no
Non-cyclic primes:   $3$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $729$ $321489$ $143712144$ $78137579961$ $41491852967889$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $30$ $604$ $11808$ $279220$ $6446490$ $148019758$ $3404640486$ $78311911204$ $1801154137824$ $41426485488364$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 15 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.d 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-83}) \)$)$

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.ag_cd$2$(not in LMFDB)
2.23.a_bl$2$(not in LMFDB)
2.23.ad_ao$3$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.23.ag_cd$2$(not in LMFDB)
2.23.a_bl$2$(not in LMFDB)
2.23.ad_ao$3$(not in LMFDB)
2.23.a_abl$4$(not in LMFDB)
2.23.d_ao$6$(not in LMFDB)