Properties

Label 2.11.a_ad
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:  $( 1 - 5 x + 11 x^{2} )( 1 + 5 x + 11 x^{2} )$
  $1 - 3 x^{2} + 121 x^{4}$
Frobenius angles:  $\pm0.228229222880$, $\pm0.771770777120$
Angle rank:  $1$ (numerical)
Jacobians:  $8$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $119$ $14161$ $1772624$ $221265625$ $25937221079$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $12$ $116$ $1332$ $15108$ $161052$ $1773686$ $19487172$ $214308868$ $2357947692$ $25937017556$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 8 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.af $\times$ 1.11.f 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.ad 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-19}) \)$)$

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.ak_bv$2$2.121.ag_jr
2.11.k_bv$2$2.121.ag_jr
2.11.a_d$4$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.11.ak_bv$2$2.121.ag_jr
2.11.k_bv$2$2.121.ag_jr
2.11.a_d$4$(not in LMFDB)
2.11.af_o$6$(not in LMFDB)
2.11.f_o$6$(not in LMFDB)