Properties

Label 2.43.ak_by
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:  $1 - 10 x + 50 x^{2} - 430 x^{3} + 1849 x^{4}$
Frobenius angles:  $\pm0.0687403460748$, $\pm0.568740346075$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(i, \sqrt{61})\)
Galois group:  $C_2^2$
Jacobians:  $78$
Cyclic group of points:    no
Non-cyclic primes:   $2$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $1460$ $3416400$ $6258863780$ $11671788960000$ $21612945096803300$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $34$ $1850$ $78718$ $3413998$ $147018394$ $6321363050$ $271817508598$ $11688202413598$ $502592670024754$ $21611482313284250$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 78 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{43^{4}}$.

Endomorphism algebra over $\F_{43}$
The endomorphism algebra of this simple isogeny class is \(\Q(i, \sqrt{61})\).
Endomorphism algebra over $\overline{\F}_{43}$
The base change of $A$ to $\F_{43^{4}}$ is 1.3418801.adok 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-61}) \)$)$
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
2.43.k_by$2$(not in LMFDB)
2.43.k_by$4$(not in LMFDB)
2.43.a_abk$8$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.43.k_by$2$(not in LMFDB)
2.43.k_by$4$(not in LMFDB)
2.43.a_abk$8$(not in LMFDB)
2.43.a_bk$8$(not in LMFDB)