Properties

Label 2.43.a_by
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:  $( 1 - 6 x + 43 x^{2} )( 1 + 6 x + 43 x^{2} )$
  $1 + 50 x^{2} + 1849 x^{4}$
Frobenius angles:  $\pm0.348746511119$, $\pm0.651253488881$
Angle rank:  $1$ (numerical)
Jacobians:  $256$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $1900$ $3610000$ $6321210700$ $11696400000000$ $21611482324859500$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $44$ $1950$ $79508$ $3421198$ $147008444$ $6321058350$ $271818611108$ $11688211082398$ $502592611936844$ $21611482336434750$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 256 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.ag $\times$ 1.43.g 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.by 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-34}) \)$)$

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.am_es$2$(not in LMFDB)
2.43.m_es$2$(not in LMFDB)
2.43.a_aby$4$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.43.am_es$2$(not in LMFDB)
2.43.m_es$2$(not in LMFDB)
2.43.a_aby$4$(not in LMFDB)
2.43.ag_ah$6$(not in LMFDB)
2.43.g_ah$6$(not in LMFDB)