Properties

Label 2.43.a_adi
Base field $\F_{43}$
Dimension $2$
$p$-rank $0$
Ordinary no
Supersingular yes
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:  $( 1 - 43 x^{2} )^{2}$
  $1 - 86 x^{2} + 1849 x^{4}$
Frobenius angles:  $0$, $0$, $1$, $1$
Angle rank:  $0$ (numerical)
Number field:  \(\Q(\sqrt{43}) \)
Galois group:  $C_2$
Jacobians:  $6$
Cyclic group of points:    no
Non-cyclic primes:   $2, 3, 7$

This isogeny class is simple but not geometrically simple, primitive, not ordinary, and supersingular. It is principally polarizable and contains a Jacobian.

Newton polygon

This isogeny class is supersingular.

$p$-rank:  $0$
Slopes:  $[1/2, 1/2, 1/2, 1/2]$

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $1764$ $3111696$ $6321204036$ $11662935330816$ $21611482019267364$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $44$ $1678$ $79508$ $3411406$ $147008444$ $6321045022$ $271818611108$ $11688186602398$ $502592611936844$ $21611481725250478$

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 the quaternion algebra over \(\Q(\sqrt{43}) \) ramified at both real infinite places.
Endomorphism algebra over $\overline{\F}_{43}$
The base change of $A$ to $\F_{43^{2}}$ is 1.1849.adi 2 and its endomorphism algebra is $\mathrm{M}_{2}(B)$, where $B$ is the quaternion algebra over \(\Q\) ramified at $43$ and $\infty$.

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.a_br$3$(not in LMFDB)
2.43.a_di$4$(not in LMFDB)
2.43.a_a$8$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.43.a_br$3$(not in LMFDB)
2.43.a_di$4$(not in LMFDB)
2.43.a_a$8$(not in LMFDB)
2.43.a_abr$12$(not in LMFDB)