Properties

Label 4.2.ae_i_an_u
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:  $( 1 - 3 x + 5 x^{2} - 6 x^{3} + 4 x^{4} )( 1 - x - 2 x^{3} + 4 x^{4} )$
  $1 - 4 x + 8 x^{2} - 13 x^{3} + 20 x^{4} - 26 x^{5} + 32 x^{6} - 32 x^{7} + 16 x^{8}$
Frobenius angles:  $\pm0.123548644961$, $\pm0.139386741866$, $\pm0.456881978294$, $\pm0.686170398078$
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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $2$ $304$ $1976$ $71136$ $1347322$

Point counts of the (virtual) curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $-1$ $5$ $2$ $17$ $39$ $86$ $209$ $305$ $506$ $1165$

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 $\F_{2}$
The isogeny class factors as 2.2.ad_f $\times$ 2.2.ab_a 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 $\F_{2^{6}}$ is 1.64.l 2 $\times$ 2.64.ab_adc. 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.ac_c_b_ae$2$4.4.a_a_h_m
4.2.c_c_ab_ae$2$4.4.a_a_h_m
4.2.e_i_n_u$2$4.4.a_a_h_m
4.2.ab_ab_ab_i$3$(not in LMFDB)
4.2.c_c_ab_ae$3$(not in LMFDB)

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

TwistExtension degreeCommon base change
4.2.ac_c_b_ae$2$4.4.a_a_h_m
4.2.c_c_ab_ae$2$4.4.a_a_h_m
4.2.e_i_n_u$2$4.4.a_a_h_m
4.2.ab_ab_ab_i$3$(not in LMFDB)
4.2.c_c_ab_ae$3$(not in LMFDB)
4.2.b_ab_b_i$6$(not in LMFDB)
4.2.ab_b_ad_i$12$(not in LMFDB)
4.2.b_b_d_i$12$(not in LMFDB)