Properties

Label 2.43.a_ade
Base field $\F_{43}$
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:  $\F_{43}$
Dimension:  $2$
L-polynomial:  $1 - 82 x^{2} + 1849 x^{4}$
Frobenius angles:  $\pm0.0487319457575$, $\pm0.951268054243$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(i, \sqrt{42})\)
Galois group:  $C_2^2$
Jacobians:  $6$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $1768$ $3125824$ $6321266536$ $11667525682176$ $21611482301574568$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $44$ $1686$ $79508$ $3412750$ $147008444$ $6321170022$ $271818611108$ $11688195639454$ $502592611936844$ $21611482289864886$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 6 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{43^{2}}$.

Endomorphism algebra over $\F_{43}$
The endomorphism algebra of this simple isogeny class is \(\Q(i, \sqrt{42})\).
Endomorphism algebra over $\overline{\F}_{43}$
The base change of $A$ to $\F_{43^{2}}$ is 1.1849.ade 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-42}) \)$)$

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.43.ae_dm$4$(not in LMFDB)
2.43.a_de$4$(not in LMFDB)
2.43.e_dm$4$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.43.ae_dm$4$(not in LMFDB)
2.43.a_de$4$(not in LMFDB)
2.43.e_dm$4$(not in LMFDB)
2.43.ac_abn$12$(not in LMFDB)
2.43.c_abn$12$(not in LMFDB)