Properties

Label 2.43.a_f
Base field $\F_{43}$
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:  $\F_{43}$
Dimension:  $2$
L-polynomial:  $( 1 - 9 x + 43 x^{2} )( 1 + 9 x + 43 x^{2} )$
  $1 + 5 x^{2} + 1849 x^{4}$
Frobenius angles:  $\pm0.259258415261$, $\pm0.740741584739$
Angle rank:  $1$ (numerical)
Jacobians:  $122$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $1855$ $3441025$ $6321335440$ $11713335125625$ $21611482397601775$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $44$ $1860$ $79508$ $3426148$ $147008444$ $6321307830$ $271818611108$ $11688186970948$ $502592611936844$ $21611482481919300$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 122 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 isogeny class factors as 1.43.aj $\times$ 1.43.j and its endomorphism algebra is a direct product of the endomorphism algebras for each isotypic factor. The endomorphism algebra for each factor is:
Endomorphism algebra over $\overline{\F}_{43}$
The base change of $A$ to $\F_{43^{2}}$ is 1.1849.f 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-91}) \)$)$

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.as_gl$2$(not in LMFDB)
2.43.s_gl$2$(not in LMFDB)
2.43.a_af$4$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.43.as_gl$2$(not in LMFDB)
2.43.s_gl$2$(not in LMFDB)
2.43.a_af$4$(not in LMFDB)
2.43.aj_bm$6$(not in LMFDB)
2.43.j_bm$6$(not in LMFDB)