Abelian variety isogeny class 2.49.aba_kg over $\F_{7^{2}}$

• Label: 2.49.aba_kg
• Base field: $\F_{7^{2}}$
• Dimension: $2$
• $p$-rank: $1$
• Ordinary: no
• Supersingular: no
• Simple: no
• Geometrically simple: no
• Primitive: yes
• Principally polarizable: yes
• Contains a Jacobian: no

Invariants

Base field:	$\F_{7^{2}}$
Dimension:	$2$
L-polynomial:	$( 1 - 7 x )^{2}( 1 - 12 x + 49 x^{2} )$
	$1 - 26 x + 266 x^{2} - 1274 x^{3} + 2401 x^{4}$
Frobenius angles:	$0$, $0$, $\pm0.172237328522$
Angle rank:	$1$ (numerical)
Jacobians:	$0$

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

Newton polygon

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

Point counts

Point counts of the abelian variety

$r$	$1$	$2$	$3$	$4$	$5$
$A(\F_{q^r})$	$1368$	$5428224$	$13765025304$	$33220730880000$	$79791377171274648$

Point counts of the (virtual) curve

$r$	$1$	$2$	$3$	$4$	$5$	$6$	$7$	$8$	$9$	$10$
$C(\F_{q^r})$	$24$	$2258$	$117000$	$5762686$	$282472104$	$13841285906$	$678222740856$	$33232923355006$	$1628413504543800$	$79792265369312978$

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 $\F_{7^{2}}$.

Endomorphism algebra over $\F_{7^{2}}$

The isogeny class factors as 1.49.ao $\times$ 1.49.am and its endomorphism algebra is a direct product of the endomorphism algebras for each isotypic factor. The endomorphism algebra for each factor is:

• 1.49.ao : the quaternion algebra over \(\Q\) ramified at $7$ and $\infty$.
• 1.49.am : \(\Q(\sqrt{-13}) \).

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
2.49.ac_acs	$2$	(not in LMFDB)
2.49.c_acs	$2$	(not in LMFDB)
2.49.ba_kg	$2$	(not in LMFDB)