Properties

Label 2.11.a_ao
Base field $\F_{11}$
Dimension $2$
$p$-rank $2$
Ordinary yes
Supersingular no
Simple no
Geometrically simple no
Primitive yes
Principally polarizable yes
Contains a Jacobian yes

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Invariants

Base field:  $\F_{11}$
Dimension:  $2$
L-polynomial:  $( 1 - 6 x + 11 x^{2} )( 1 + 6 x + 11 x^{2} )$
  $1 - 14 x^{2} + 121 x^{4}$
Frobenius angles:  $\pm0.140218899004$, $\pm0.859781100996$
Angle rank:  $1$ (numerical)
Jacobians:  $6$
Cyclic group of points:    no
Non-cyclic primes:   $2, 3$

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

Newton polygon

This isogeny class is ordinary.

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

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $108$ $11664$ $1773900$ $215737344$ $25937522028$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $12$ $94$ $1332$ $14734$ $161052$ $1776238$ $19487172$ $214413214$ $2357947692$ $25937619454$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 6 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{11^{2}}$.

Endomorphism algebra over $\F_{11}$
The isogeny class factors as 1.11.ag $\times$ 1.11.g and its endomorphism algebra is a direct product of the endomorphism algebras for each isotypic factor. The endomorphism algebra for each factor is:
Endomorphism algebra over $\overline{\F}_{11}$
The base change of $A$ to $\F_{11^{2}}$ is 1.121.ao 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-2}) \)$)$

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.11.am_cg$2$2.121.abc_qw
2.11.m_cg$2$2.121.abc_qw
2.11.a_o$4$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.11.am_cg$2$2.121.abc_qw
2.11.m_cg$2$2.121.abc_qw
2.11.a_o$4$(not in LMFDB)
2.11.ag_z$6$(not in LMFDB)
2.11.g_z$6$(not in LMFDB)
2.11.ae_i$8$(not in LMFDB)
2.11.e_i$8$(not in LMFDB)