Properties

Label 2.2.c_c
Base field $\F_{2}$
Dimension $2$
$p$-rank $0$
Ordinary No
Supersingular Yes
Simple Yes
Geometrically simple No
Primitive Yes
Principally polarizable Yes
Contains a Jacobian Yes

Learn more about

Invariants

Base field:  $\F_{2}$
Dimension:  $2$
L-polynomial:  $1 + 2 x + 2 x^{2} + 4 x^{3} + 4 x^{4}$
Frobenius angles:  $\pm0.416666666667$, $\pm0.916666666667$
Angle rank:  $0$ (numerical)
Number field:  \(\Q(\zeta_{12})\)
Galois group:  $C_2^2$
Jacobians:  1

This isogeny class is simple but not geometrically simple.

Newton polygon

This isogeny class is supersingular.

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

Point counts

This isogeny class contains the Jacobians of 1 curves, and hence is principally polarizable:

Point counts of the abelian variety

$r$ 1 2 3 4 5 6 7 8 9 10
$A(\F_{q^r})$ 13 13 169 169 793 4225 18577 74529 231361 1047553

Point counts of the curve

$r$ 1 2 3 4 5 6 7 8 9 10
$C(\F_{q^r})$ 5 5 17 9 25 65 145 289 449 1025

Decomposition and endomorphism algebra

Endomorphism algebra over $\F_{2}$
The endomorphism algebra of this simple isogeny class is \(\Q(\zeta_{12})\).
Endomorphism algebra over $\overline{\F}_{2}$
The base change of $A$ to $\F_{2^{12}}$ is 1.4096.ey 2 and its endomorphism algebra is $\mathrm{M}_{2}(B)$, where $B$ is the quaternion algebra over \(\Q\) ramified at $2$ and $\infty$.
All geometric endomorphisms are defined over $\F_{2^{12}}$.
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
2.2.ac_c$2$2.4.a_ae
2.2.ae_i$3$2.8.i_bg
2.2.a_a$6$2.64.a_ey
Below is a list of all twists of this isogeny class.
TwistExtension DegreeCommon base change
2.2.ac_c$2$2.4.a_ae
2.2.ae_i$3$2.8.i_bg
2.2.a_a$6$2.64.a_ey
2.2.e_i$6$2.64.a_ey
2.2.a_ac$8$2.256.bg_bdo
2.2.a_c$8$2.256.bg_bdo
2.2.ac_e$24$(not in LMFDB)
2.2.a_ae$24$(not in LMFDB)
2.2.a_e$24$(not in LMFDB)
2.2.c_e$24$(not in LMFDB)