Abelian variety isogeny class 4.5.al_cg_ahr_tm over $\F_{5}$

• Label: 4.5.al_cg_ahr_tm
• Base field: $\F_{5}$
• Dimension: $4$
• $p$-rank: $4$
• Ordinary: yes
• Supersingular: no
• Simple: no
• Geometrically simple: no
• Primitive: yes
• Principally polarizable: yes
• Contains a Jacobian: no

Invariants

Base field:	$\F_{5}$
Dimension:	$4$
L-polynomial:	$( 1 - 4 x + 5 x^{2} )( 1 - 3 x + 5 x^{2} )( 1 - 4 x + 8 x^{2} - 20 x^{3} + 25 x^{4} )$
	$1 - 11 x + 58 x^{2} - 199 x^{3} + 506 x^{4} - 995 x^{5} + 1450 x^{6} - 1375 x^{7} + 625 x^{8}$
Frobenius angles:	$\pm0.0320471084245$, $\pm0.147583617650$, $\pm0.265942140215$, $\pm0.532047108424$
Angle rank:	$3$ (numerical)

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

$r$	$1$	$2$	$3$	$4$	$5$
$A(\F_{q^r})$	$60$	$313200$	$219424320$	$145324800000$	$98138950212300$

Point counts of the (virtual) curve

$r$	$1$	$2$	$3$	$4$	$5$	$6$	$7$	$8$	$9$	$10$
$C(\F_{q^r})$	$-5$	$21$	$112$	$597$	$3215$	$15786$	$77387$	$388797$	$1954120$	$9769101$

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 $\F_{5^{4}}$.

Endomorphism algebra over $\F_{5}$

The isogeny class factors as 1.5.ae $\times$ 1.5.ad $\times$ 2.5.ae_i and its endomorphism algebra is a direct product of the endomorphism algebras for each isotypic factor. The endomorphism algebra for each factor is:

• 1.5.ae : \(\Q(\sqrt{-1}) \).
• 1.5.ad : \(\Q(\sqrt{-11}) \).
• 2.5.ae_i : \(\Q(i, \sqrt{6})\).

Endomorphism algebra over $\overline{\F}_{5}$

The base change of $A$ to $\F_{5^{4}}$ is 1.625.abu^2 $\times$ 1.625.o $\times$ 1.625.bx. The endomorphism algebra for each factor is:

• 1.625.abu^2 : $\mathrm{M}_{2}($\(\Q(\sqrt{-6}) \)$)$
• 1.625.o : \(\Q(\sqrt{-1}) \).
• 1.625.bx : \(\Q(\sqrt{-11}) \).

Remainder of endomorphism lattice by field

• Endomorphism algebra over $\F_{5^{2}}$
  The base change of $A$ to $\F_{5^{2}}$ is 1.25.ag $\times$ 1.25.b $\times$ 2.25.a_abu. The endomorphism algebra for each factor is:

  • 1.25.ag : \(\Q(\sqrt{-1}) \).
  • 1.25.b : \(\Q(\sqrt{-11}) \).
  • 2.25.a_abu : \(\Q(i, \sqrt{6})\).

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
4.5.af_k_az_cw	$2$	(not in LMFDB)
4.5.ad_c_b_ag	$2$	(not in LMFDB)
4.5.ad_c_r_acc	$2$	(not in LMFDB)
4.5.d_c_ar_acc	$2$	(not in LMFDB)
4.5.d_c_ab_ag	$2$	(not in LMFDB)
4.5.f_k_z_cw	$2$	(not in LMFDB)
4.5.l_cg_hr_tm	$2$	(not in LMFDB)