Properties

Label 2.43.au_hb
Base field $\F_{43}$
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:  $\F_{43}$
Dimension:  $2$
L-polynomial:  $1 - 20 x + 183 x^{2} - 860 x^{3} + 1849 x^{4}$
Frobenius angles:  $\pm0.147488713818$, $\pm0.282880549156$
Angle rank:  $2$ (numerical)
Number field:  \(\Q(\sqrt{-69 +20 \sqrt{3}})\)
Galois group:  $D_{4}$
Jacobians:  $6$
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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $1153$ $3358689$ $6353274436$ $11703314874921$ $21614849206697593$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $24$ $1816$ $79908$ $3423220$ $147031344$ $6321419422$ $271818607728$ $11688201419044$ $502592641522044$ $21611482588965736$

Jacobians and polarizations

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

  • $y^2=32 x^6+24 x^5+10 x^4+25 x^3+40 x^2+14 x+18$
  • $y^2=24 x^6+11 x^5+17 x^4+32 x^3+38 x^2+2 x+31$
  • $y^2=22 x^6+5 x^5+10 x^4+21 x^3+41 x^2+11 x+36$
  • $y^2=15 x^6+23 x^5+x^4+20 x^3+41 x^2+14 x+26$
  • $y^2=8 x^6+37 x^5+28 x^4+18 x^3+26 x^2+22 x+18$
  • $y^2=36 x^6+19 x^5+29 x^4+38 x^3+36 x^2+34 x+42$

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{43}$.

Endomorphism algebra over $\F_{43}$
The endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{-69 +20 \sqrt{3}})\).

Base change

This is a primitive isogeny class.

Twists

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

TwistExtension degreeCommon base change
2.43.u_hb$2$(not in LMFDB)