Properties

Label 2.11.ag_bf
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:  $( 1 - 3 x + 11 x^{2} )^{2}$
  $1 - 6 x + 31 x^{2} - 66 x^{3} + 121 x^{4}$
Frobenius angles:  $\pm0.350615407277$, $\pm0.350615407277$
Angle rank:  $1$ (numerical)
Jacobians:  $5$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $81$ $18225$ $1971216$ $216531225$ $25753509441$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $6$ $148$ $1476$ $14788$ $159906$ $1766518$ $19484646$ $214406788$ $2358119196$ $25937412148$

Jacobians and polarizations

This isogeny class contains the Jacobians of 5 curves (of which all are hyperelliptic), and hence is principally polarizable:

Decomposition and endomorphism algebra

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

Endomorphism algebra over $\F_{11}$
The isogeny class factors as 1.11.ad 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-35}) \)$)$

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.a_n$2$2.121.ba_pv
2.11.g_bf$2$2.121.ba_pv
2.11.d_ac$3$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.11.a_n$2$2.121.ba_pv
2.11.g_bf$2$2.121.ba_pv
2.11.d_ac$3$(not in LMFDB)
2.11.a_an$4$(not in LMFDB)
2.11.ad_ac$6$(not in LMFDB)