Properties

Label 2.8.b_q
Base field $\F_{2^{3}}$
Dimension $2$
$p$-rank $1$
Ordinary no
Supersingular no
Simple no
Geometrically simple no
Primitive yes
Principally polarizable yes
Contains a Jacobian no

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Invariants

Base field:  $\F_{2^{3}}$
Dimension:  $2$
L-polynomial:  $( 1 + 8 x^{2} )( 1 + x + 8 x^{2} )$
  $1 + x + 16 x^{2} + 8 x^{3} + 64 x^{4}$
Frobenius angles:  $\pm0.5$, $\pm0.556567041129$
Angle rank:  $1$ (numerical)
Jacobians:  $0$
Cyclic group of points:    yes

This isogeny class is not simple, primitive, not ordinary, and not supersingular. It is principally polarizable.

Newton polygon

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

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $90$ $6480$ $251370$ $15876000$ $1083015450$

Point counts of the (virtual) curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $10$ $96$ $490$ $3872$ $33050$ $263664$ $2094410$ $16767808$ $134240890$ $1073793936$

Jacobians and polarizations

This isogeny class is principally polarizable, but does not contain a Jacobian.

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{2^{6}}$.

Endomorphism algebra over $\F_{2^{3}}$
The isogeny class factors as 1.8.a $\times$ 1.8.b 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 $\overline{\F}_{2^{3}}$
The base change of $A$ to $\F_{2^{6}}$ is 1.64.p $\times$ 1.64.q. The endomorphism algebra for each factor is:

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.8.ab_q$2$2.64.bf_oe
2.8.af_u$8$(not in LMFDB)
2.8.ad_m$8$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.8.ab_q$2$2.64.bf_oe
2.8.af_u$8$(not in LMFDB)
2.8.ad_m$8$(not in LMFDB)
2.8.d_m$8$(not in LMFDB)
2.8.f_u$8$(not in LMFDB)