Properties

Label 4.2.af_o_abb_bq
Base field $\F_{2}$
Dimension $4$
$p$-rank $3$
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:  $\F_{2}$
Dimension:  $4$
L-polynomial:  $( 1 - 2 x + 2 x^{2} )( 1 - 3 x + 6 x^{2} - 9 x^{3} + 12 x^{4} - 12 x^{5} + 8 x^{6} )$
  $1 - 5 x + 14 x^{2} - 27 x^{3} + 42 x^{4} - 54 x^{5} + 56 x^{6} - 40 x^{7} + 16 x^{8}$
Frobenius angles:  $\pm0.147012170705$, $\pm0.250000000000$, $\pm0.341962716420$, $\pm0.600633654388$
Angle rank:  $3$ (numerical)
Jacobians:  $0$
Isomorphism classes:  1

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

Newton polygon

$p$-rank:  $3$
Slopes:  $[0, 0, 0, 1/2, 1/2, 1, 1, 1]$

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $3$ $765$ $6669$ $141525$ $1923843$

Point counts of the (virtual) curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $-2$ $8$ $13$ $28$ $53$ $59$ $110$ $300$ $562$ $983$

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 $\F_{2^{4}}$.

Endomorphism algebra over $\F_{2}$
The isogeny class factors as 1.2.ac $\times$ 3.2.ad_g_aj 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 $\overline{\F}_{2}$
The base change of $A$ to $\F_{2^{4}}$ is 1.16.i $\times$ 3.16.d_bq_db. The endomorphism algebra for each factor is:
Remainder of endomorphism lattice by field

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
4.2.ab_c_ad_g$2$4.4.d_k_t_bw
4.2.b_c_d_g$2$4.4.d_k_t_bw
4.2.f_o_bb_bq$2$4.4.d_k_t_bw

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

TwistExtension degreeCommon base change
4.2.ab_c_ad_g$2$4.4.d_k_t_bw
4.2.b_c_d_g$2$4.4.d_k_t_bw
4.2.f_o_bb_bq$2$4.4.d_k_t_bw
4.2.ad_i_ap_y$8$(not in LMFDB)
4.2.d_i_p_y$8$(not in LMFDB)