Properties

Label 4.2.ag_t_abq_cr
Base field $\F_{2}$
Dimension $4$
$p$-rank $4$
Ordinary yes
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:  $( 1 - 3 x + 5 x^{2} - 6 x^{3} + 4 x^{4} )^{2}$
  $1 - 6 x + 19 x^{2} - 42 x^{3} + 69 x^{4} - 84 x^{5} + 76 x^{6} - 48 x^{7} + 16 x^{8}$
Frobenius angles:  $\pm0.123548644961$, $\pm0.123548644961$, $\pm0.456881978294$, $\pm0.456881978294$
Angle rank:  $1$ (numerical)
Jacobians:  $0$

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

Newton polygon

This isogeny class is ordinary.

$p$-rank:  $4$
Slopes:  $[0, 0, 0, 0, 1, 1, 1, 1]$

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $1$ $361$ $5776$ $29241$ $923521$

Point counts of the (virtual) curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $-3$ $7$ $9$ $3$ $27$ $109$ $207$ $291$ $513$ $1147$

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 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-3}, \sqrt{5})\)$)$
Endomorphism algebra over $\overline{\F}_{2}$
The base change of $A$ to $\F_{2^{6}}$ is 1.64.l 4 and its endomorphism algebra is $\mathrm{M}_{4}($\(\Q(\sqrt{-15}) \)$)$
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.a_b_a_ad$2$4.4.c_af_c_bx
4.2.g_t_bq_cr$2$4.4.c_af_c_bx
4.2.ad_e_ad_d$3$(not in LMFDB)
4.2.a_ac_a_j$3$(not in LMFDB)
4.2.a_b_a_ad$3$(not in LMFDB)
4.2.d_e_d_d$3$(not in LMFDB)
4.2.g_t_bq_cr$3$(not in LMFDB)

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

TwistExtension degreeCommon base change
4.2.a_b_a_ad$2$4.4.c_af_c_bx
4.2.g_t_bq_cr$2$4.4.c_af_c_bx
4.2.ad_e_ad_d$3$(not in LMFDB)
4.2.a_ac_a_j$3$(not in LMFDB)
4.2.a_b_a_ad$3$(not in LMFDB)
4.2.d_e_d_d$3$(not in LMFDB)
4.2.g_t_bq_cr$3$(not in LMFDB)
4.2.a_ab_a_ad$4$(not in LMFDB)
4.2.ab_e_ac_j$5$(not in LMFDB)
4.2.e_e_ah_av$5$(not in LMFDB)
4.2.ae_e_h_av$10$(not in LMFDB)
4.2.b_e_c_j$10$(not in LMFDB)
4.2.ad_g_aj_n$12$(not in LMFDB)
4.2.a_a_a_h$12$(not in LMFDB)
4.2.a_c_a_j$12$(not in LMFDB)
4.2.d_g_j_n$12$(not in LMFDB)
4.2.af_n_az_bn$15$(not in LMFDB)
4.2.ae_e_h_av$15$(not in LMFDB)
4.2.b_e_c_j$15$(not in LMFDB)
4.2.f_n_z_bn$15$(not in LMFDB)
4.2.a_a_a_ah$24$(not in LMFDB)