Properties

Label 4.4.ak_by_agj_oy
Base field $\F_{2^{2}}$
Dimension $4$
$p$-rank $3$
Ordinary no
Supersingular no
Simple no
Geometrically simple no
Primitive yes
Principally polarizable yes
Contains a Jacobian no

Downloads

Learn more

Invariants

Base field:  $\F_{2^{2}}$
Dimension:  $4$
L-polynomial:  $( 1 - 2 x )^{2}( 1 - x + 4 x^{2} )( 1 - 5 x + 13 x^{2} - 20 x^{3} + 16 x^{4} )$
  $1 - 10 x + 50 x^{2} - 165 x^{3} + 388 x^{4} - 660 x^{5} + 800 x^{6} - 640 x^{7} + 256 x^{8}$
Frobenius angles:  $0$, $0$, $\pm0.140237960897$, $\pm0.387712212190$, $\pm0.419569376745$
Angle rank:  $3$ (numerical)

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $20$ $59400$ $17949680$ $3578850000$ $947363890500$

Point counts of the (virtual) curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $-5$ $17$ $70$ $209$ $875$ $4022$ $16795$ $66209$ $261070$ $1043577$

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

Endomorphism algebra over $\F_{2^{2}}$
The isogeny class factors as 1.4.ae $\times$ 1.4.ab $\times$ 2.4.af_n and its endomorphism algebra is a direct product of the endomorphism algebras for each isotypic factor. 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
4.4.ai_bg_adn_hw$2$(not in LMFDB)
4.4.ac_c_l_abk$2$(not in LMFDB)
4.4.a_a_af_am$2$(not in LMFDB)
4.4.a_a_f_am$2$(not in LMFDB)
4.4.c_c_al_abk$2$(not in LMFDB)
4.4.i_bg_dn_hw$2$(not in LMFDB)
4.4.k_by_gj_oy$2$(not in LMFDB)
4.4.ae_o_abh_cs$3$(not in LMFDB)

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

TwistExtension degreeCommon base change
4.4.ai_bg_adn_hw$2$(not in LMFDB)
4.4.ac_c_l_abk$2$(not in LMFDB)
4.4.a_a_af_am$2$(not in LMFDB)
4.4.a_a_f_am$2$(not in LMFDB)
4.4.c_c_al_abk$2$(not in LMFDB)
4.4.i_bg_dn_hw$2$(not in LMFDB)
4.4.k_by_gj_oy$2$(not in LMFDB)
4.4.ae_o_abh_cs$3$(not in LMFDB)
4.4.ag_ba_acz_gu$4$(not in LMFDB)
4.4.ae_q_abr_ds$4$(not in LMFDB)
4.4.e_q_br_ds$4$(not in LMFDB)
4.4.g_ba_cz_gu$4$(not in LMFDB)
4.4.ai_bm_aer_kw$6$(not in LMFDB)
4.4.ag_y_acp_fu$6$(not in LMFDB)
4.4.ac_i_at_bq$6$(not in LMFDB)
4.4.c_i_t_bq$6$(not in LMFDB)
4.4.e_o_bh_cs$6$(not in LMFDB)
4.4.g_y_cp_fu$6$(not in LMFDB)
4.4.i_bm_er_kw$6$(not in LMFDB)