Properties

Label 2.43.a_o
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:  $1 + 14 x^{2} + 1849 x^{4}$
Frobenius angles:  $\pm0.276024765496$, $\pm0.723975234504$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(\zeta_{8})\)
Galois group:  $C_2^2$
Jacobians:  $176$
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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $1864$ $3474496$ $6321288136$ $11712164668416$ $21611482527769864$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $44$ $1878$ $79508$ $3425806$ $147008444$ $6321213222$ $271818611108$ $11688189424798$ $502592611936844$ $21611482742255478$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 176 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 \(\Q(\zeta_{8})\).
Endomorphism algebra over $\overline{\F}_{43}$
The base change of $A$ to $\F_{43^{2}}$ is 1.1849.o 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-2}) \)$)$

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.au_he$4$(not in LMFDB)
2.43.a_ao$4$(not in LMFDB)
2.43.u_he$4$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.43.au_he$4$(not in LMFDB)
2.43.a_ao$4$(not in LMFDB)
2.43.u_he$4$(not in LMFDB)
2.43.am_cu$8$(not in LMFDB)
2.43.m_cu$8$(not in LMFDB)
2.43.ak_cf$12$(not in LMFDB)
2.43.k_cf$12$(not in LMFDB)