Properties

Label 4.2.af_p_abg_ca
Base field $\F_{2}$
Dimension $4$
$p$-rank $2$
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:  $( 1 - 2 x + 2 x^{2} )( 1 + 2 x^{2} )( 1 - 3 x + 5 x^{2} - 6 x^{3} + 4 x^{4} )$
  $1 - 5 x + 15 x^{2} - 32 x^{3} + 52 x^{4} - 64 x^{5} + 60 x^{6} - 40 x^{7} + 16 x^{8}$
Frobenius angles:  $\pm0.123548644961$, $\pm0.250000000000$, $\pm0.456881978294$, $\pm0.5$
Angle rank:  $1$ (numerical)
Jacobians:  $0$
Isomorphism classes:  3

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

Newton polygon

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

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $3$ $855$ $8892$ $38475$ $1300233$

Point counts of the (virtual) curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $-2$ $10$ $13$ $10$ $38$ $103$ $152$ $210$ $481$ $1150$

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 $\F_{2^{24}}$.

Endomorphism algebra over $\F_{2}$
The isogeny class factors as 1.2.ac $\times$ 1.2.a $\times$ 2.2.ad_f 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 $\F_{2^{24}}$ is 1.16777216.amdc 2 $\times$ 1.16777216.mbf 2 . 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_d_ae_e$2$4.4.f_j_q_bo
4.2.b_d_e_e$2$4.4.f_j_q_bo
4.2.f_p_bg_ca$2$4.4.f_j_q_bo
4.2.ac_d_ac_e$3$(not in LMFDB)
4.2.b_d_e_e$3$(not in LMFDB)

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

TwistExtension degreeCommon base change
4.2.ab_d_ae_e$2$4.4.f_j_q_bo
4.2.b_d_e_e$2$4.4.f_j_q_bo
4.2.f_p_bg_ca$2$4.4.f_j_q_bo
4.2.ac_d_ac_e$3$(not in LMFDB)
4.2.b_d_e_e$3$(not in LMFDB)
4.2.c_d_c_e$6$(not in LMFDB)
4.2.ah_z_acg_ds$8$(not in LMFDB)
4.2.ad_b_g_am$8$(not in LMFDB)
4.2.ad_f_ag_i$8$(not in LMFDB)
4.2.ad_j_as_bc$8$(not in LMFDB)
4.2.ab_b_c_a$8$(not in LMFDB)
4.2.b_b_ac_a$8$(not in LMFDB)
4.2.d_b_ag_am$8$(not in LMFDB)
4.2.d_f_g_i$8$(not in LMFDB)
4.2.d_j_s_bc$8$(not in LMFDB)
4.2.h_z_cg_ds$8$(not in LMFDB)
4.2.ac_f_ag_m$12$(not in LMFDB)
4.2.c_f_g_m$12$(not in LMFDB)
4.2.af_n_aba_bq$24$(not in LMFDB)
4.2.ae_h_ae_a$24$(not in LMFDB)
4.2.ae_j_am_q$24$(not in LMFDB)
4.2.ad_d_a_ac$24$(not in LMFDB)
4.2.ad_h_am_s$24$(not in LMFDB)
4.2.ac_b_ac_g$24$(not in LMFDB)
4.2.ac_d_ag_k$24$(not in LMFDB)
4.2.ab_b_c_ag$24$(not in LMFDB)
4.2.a_af_a_m$24$(not in LMFDB)
4.2.a_ad_a_e$24$(not in LMFDB)
4.2.a_ad_a_k$24$(not in LMFDB)
4.2.a_ab_a_g$24$(not in LMFDB)
4.2.a_ab_a_i$24$(not in LMFDB)
4.2.a_b_a_g$24$(not in LMFDB)
4.2.a_b_a_i$24$(not in LMFDB)
4.2.a_d_a_e$24$(not in LMFDB)
4.2.a_d_a_k$24$(not in LMFDB)
4.2.a_f_a_m$24$(not in LMFDB)
4.2.b_b_ac_ag$24$(not in LMFDB)
4.2.c_b_c_g$24$(not in LMFDB)
4.2.c_d_g_k$24$(not in LMFDB)
4.2.d_d_a_ac$24$(not in LMFDB)
4.2.d_h_m_s$24$(not in LMFDB)
4.2.e_h_e_a$24$(not in LMFDB)
4.2.e_j_m_q$24$(not in LMFDB)
4.2.f_n_ba_bq$24$(not in LMFDB)