Properties

Label 2.11.e_q
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:  $1 + 4 x + 16 x^{2} + 44 x^{3} + 121 x^{4}$
Frobenius angles:  $\pm0.443936343938$, $\pm0.783888630716$
Angle rank:  $2$ (numerical)
Number field:  \(\Q(\sqrt{-30 +4 \sqrt{10}})\)
Galois group:  $D_{4}$
Jacobians:  $8$
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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $186$ $16740$ $1778346$ $214874640$ $25713399066$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $16$ $138$ $1336$ $14678$ $159656$ $1774458$ $19495856$ $214334878$ $2357946256$ $25937081898$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 8 curves (of which all are hyperelliptic):

  • $y^2=2 x^6+5 x^5+8 x^4+7 x^3+x^2+5 x$
  • $y^2=3 x^6+6 x^5+6 x^4+2 x^3+4 x^2+x+5$
  • $y^2=9 x^6+2 x^5+10 x^4+3 x^3+4 x^2+7 x+3$
  • $y^2=x^6+2 x^4+6 x^3+2 x^2+6 x+6$
  • $y^2=3 x^6+10 x^5+5 x^3+x^2+9 x$
  • $y^2=6 x^6+6 x^5+4 x^4+8 x^3+9$
  • $y^2=4 x^6+9 x^5+4 x^4+6 x^3+8 x^2+7 x+7$
  • $y^2=9 x^6+4 x^4+5 x^3+10 x^2+4 x+10$

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 \(\Q(\sqrt{-30 +4 \sqrt{10}})\).

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.ae_q$2$2.121.q_fq