Properties

Label 2.43.at_gj
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:  $1 - 19 x + 165 x^{2} - 817 x^{3} + 1849 x^{4}$
Frobenius angles:  $\pm0.0635826053657$, $\pm0.344751241674$
Angle rank:  $2$ (numerical)
Number field:  \(\Q(\sqrt{-33 +6 \sqrt{5}})\)
Galois group:  $D_{4}$
Jacobians:  $8$
Cyclic group of points:    no
Non-cyclic primes:   $3$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $1179$ $3361329$ $6328814229$ $11684077082541$ $21607248381873264$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $25$ $1819$ $79603$ $3417595$ $146979640$ $6321149863$ $271818151441$ $11688205418659$ $502592664546799$ $21611482483233814$

Jacobians and polarizations

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

  • $y^2=37 x^6+11 x^5+21 x^4+19 x^3+23 x^2+9 x+21$
  • $y^2=20 x^6+7 x^5+39 x^4+17 x^3+18 x^2+18 x+37$
  • $y^2=30 x^6+35 x^4+31 x^3+20 x^2+24 x+9$
  • $y^2=19 x^6+37 x^5+15 x^4+4 x^3+19 x^2+17 x+2$
  • $y^2=9 x^6+x^5+5 x^4+23 x^3+6 x^2+42 x+15$
  • $y^2=3 x^6+16 x^5+30 x^4+23 x^3+33 x^2+10 x+27$
  • $y^2=10 x^6+23 x^5+22 x^4+39 x^3+41 x^2+30 x+22$
  • $y^2=12 x^6+34 x^5+16 x^4+18 x^3+20 x^2+39 x+8$

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 \(\Q(\sqrt{-33 +6 \sqrt{5}})\).

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.t_gj$2$(not in LMFDB)