Properties

Label 2.23.a_x
Base field $\F_{23}$
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:  $\F_{23}$
Dimension:  $2$
L-polynomial:  $1 + 23 x^{2} + 529 x^{4}$
Frobenius angles:  $\pm0.333333333333$, $\pm0.666666666667$
Angle rank:  $0$ (numerical)
Number field:  \(\Q(\sqrt{-3}, \sqrt{23})\)
Galois group:  $C_2^2$
Jacobians:  $35$
Cyclic group of points:    yes

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $553$ $305809$ $148011556$ $78607897641$ $41426517649993$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $24$ $576$ $12168$ $280900$ $6436344$ $147987222$ $3404825448$ $78311544964$ $1801152661464$ $41426524086336$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 35 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{23^{6}}$.

Endomorphism algebra over $\F_{23}$
The endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{-3}, \sqrt{23})\).
Endomorphism algebra over $\overline{\F}_{23}$
The base change of $A$ to $\F_{23^{6}}$ is 1.148035889.abjzy 2 and its endomorphism algebra is $\mathrm{M}_{2}(B)$, where $B$ is the quaternion algebra over \(\Q\) ramified at $23$ and $\infty$.
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.a_abu$3$(not in LMFDB)
2.23.a_ax$4$(not in LMFDB)
2.23.a_ax$12$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.23.a_abu$3$(not in LMFDB)
2.23.a_ax$4$(not in LMFDB)
2.23.a_ax$12$(not in LMFDB)
2.23.a_bu$12$(not in LMFDB)
2.23.a_a$24$(not in LMFDB)