Properties

Label 2.23.i_bg
Base field $\F_{23}$
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:  $\F_{23}$
Dimension:  $2$
L-polynomial:  $1 + 8 x + 32 x^{2} + 184 x^{3} + 529 x^{4}$
Frobenius angles:  $\pm0.450780744796$, $\pm0.950780744796$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(i, \sqrt{30})\)
Galois group:  $C_2^2$
Jacobians:  $10$
Cyclic group of points:    yes

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $754$ $278980$ $151681426$ $77829840400$ $41427077615794$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $32$ $530$ $12464$ $278118$ $6436432$ $148035890$ $3404983264$ $78310618558$ $1801150498592$ $41426511213650$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 10 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{23^{4}}$.

Endomorphism algebra over $\F_{23}$
The endomorphism algebra of this simple isogeny class is \(\Q(i, \sqrt{30})\).
Endomorphism algebra over $\overline{\F}_{23}$
The base change of $A$ to $\F_{23^{4}}$ is 1.279841.abhe 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-30}) \)$)$
Remainder of endomorphism lattice by field

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.ai_bg$2$(not in LMFDB)
2.23.ai_bg$4$(not in LMFDB)
2.23.a_ao$8$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.23.ai_bg$2$(not in LMFDB)
2.23.ai_bg$4$(not in LMFDB)
2.23.a_ao$8$(not in LMFDB)
2.23.a_o$8$(not in LMFDB)