Abelian variety isogeny class 3.4.ah_ba_acm over $\F_{2^{2}}$

• Label: 3.4.ah_ba_acm
• Base field: $\F_{2^{2}}$
• Dimension: $3$
• $p$-rank: $1$
• Ordinary: no
• Supersingular: no
• Simple: no
• Geometrically simple: no
• Primitive: yes
• Principally polarizable: yes
• Contains a Jacobian: no

Invariants

Base field:	$\F_{2^{2}}$
Dimension:	$3$
L-polynomial:	$( 1 - 2 x )^{2}( 1 - 2 x + 4 x^{2} )( 1 - x + 4 x^{2} )$
	$1 - 7 x + 26 x^{2} - 64 x^{3} + 104 x^{4} - 112 x^{5} + 64 x^{6}$
Frobenius angles:	$0$, $0$, $\pm0.333333333333$, $\pm0.419569376745$
Angle rank:	$1$ (numerical)

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

Newton polygon

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

Point counts

Point counts of the abelian variety

$r$	$1$	$2$	$3$	$4$	$5$
$A(\F_{q^r})$	$12$	$4536$	$301644$	$14742000$	$919919172$

Point counts of the (virtual) curve

$r$	$1$	$2$	$3$	$4$	$5$	$6$	$7$	$8$	$9$	$10$
$C(\F_{q^r})$	$-2$	$20$	$76$	$224$	$868$	$3848$	$16252$	$65504$	$261364$	$1045880$

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 $\F_{2^{12}}$.

Endomorphism algebra over $\F_{2^{2}}$

The isogeny class factors as 1.4.ae $\times$ 1.4.ac $\times$ 1.4.ab and its endomorphism algebra is a direct product of the endomorphism algebras for each isotypic factor. The endomorphism algebra for each factor is:

• 1.4.ae : the quaternion algebra over \(\Q\) ramified at $2$ and $\infty$.
• 1.4.ac : \(\Q(\sqrt{-3}) \).
• 1.4.ab : \(\Q(\sqrt{-15}) \).

Endomorphism algebra over $\overline{\F}_{2^{2}}$

The base change of $A$ to $\F_{2^{12}}$ is 1.4096.aey^2 $\times$ 1.4096.h. The endomorphism algebra for each factor is:

• 1.4096.aey^2 : $\mathrm{M}_{2}(B)$, where $B$ is the quaternion algebra over \(\Q\) ramified at $2$ and $\infty$.
• 1.4096.h : \(\Q(\sqrt{-15}) \).

Remainder of endomorphism lattice by field

• Endomorphism algebra over $\F_{2^{4}}$
  The base change of $A$ to $\F_{2^{4}}$ is 1.16.ai $\times$ 1.16.e $\times$ 1.16.h. The endomorphism algebra for each factor is:

  • 1.16.ai : the quaternion algebra over \(\Q\) ramified at $2$ and $\infty$.
  • 1.16.e : \(\Q(\sqrt{-3}) \).
  • 1.16.h : \(\Q(\sqrt{-15}) \).
• Endomorphism algebra over $\F_{2^{6}}$
  The base change of $A$ to $\F_{2^{6}}$ is 1.64.aq $\times$ 1.64.l $\times$ 1.64.q. The endomorphism algebra for each factor is:

  • 1.64.aq : the quaternion algebra over \(\Q\) ramified at $2$ and $\infty$.
  • 1.64.l : \(\Q(\sqrt{-15}) \).
  • 1.64.q : the quaternion algebra over \(\Q\) ramified at $2$ and $\infty$.

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

Twist	Extension degree	Common base change
3.4.af_o_abg	$2$	3.16.d_am_aey
3.4.ad_g_aq	$2$	3.16.d_am_aey
3.4.ab_c_aq	$2$	3.16.d_am_aey
3.4.b_c_q	$2$	3.16.d_am_aey
3.4.d_g_q	$2$	3.16.d_am_aey
3.4.f_o_bg	$2$	3.16.d_am_aey
3.4.h_ba_cm	$2$	3.16.d_am_aey
3.4.ab_ae_i	$3$	(not in LMFDB)
3.4.ab_i_ae	$3$	(not in LMFDB)
3.4.f_o_bg	$3$	(not in LMFDB)