Properties

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

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Invariants

Base field:  $\F_{11}$
Dimension:  $2$
L-polynomial:  $1 + 6 x + 29 x^{2} + 66 x^{3} + 121 x^{4}$
Frobenius angles:  $\pm0.576841329034$, $\pm0.731767881221$
Angle rank:  $2$ (numerical)
Number field:  \(\Q(\sqrt{-33 -6 \sqrt{2}})\)
Galois group:  $D_{4}$
Jacobians:  $2$
Isomorphism classes:  2
Cyclic group of points:    yes

This isogeny class is simple and geometrically 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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $223$ $17617$ $1633252$ $215790633$ $25996403623$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $18$ $144$ $1224$ $14740$ $161418$ $1770990$ $19486590$ $214342948$ $2358053640$ $25937358624$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 2 curves (of which all are hyperelliptic):

  • $y^2=4 x^6+6 x^4+4 x^3+10 x^2+2 x+5$
  • $y^2=6 x^6+10 x^5+6 x^4+7 x^3+2 x^2+2 x+3$

Decomposition and endomorphism algebra

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

Endomorphism algebra over $\F_{11}$
The endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{-33 -6 \sqrt{2}})\).

Base change

This is a primitive isogeny class.

Twists

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

TwistExtension degreeCommon base change
2.11.ag_bd$2$2.121.w_lf