Properties

Label 2.43.a_cs
Base field $\F_{43}$
Dimension $2$
$p$-rank $2$
Ordinary yes
Supersingular no
Simple no
Geometrically simple no
Primitive yes
Principally polarizable yes
Contains a Jacobian yes

Related objects

Downloads

Learn more

Invariants

Base field:  $\F_{43}$
Dimension:  $2$
L-polynomial:  $( 1 - 4 x + 43 x^{2} )( 1 + 4 x + 43 x^{2} )$
  $1 + 70 x^{2} + 1849 x^{4}$
Frobenius angles:  $\pm0.401344489543$, $\pm0.598655510457$
Angle rank:  $1$ (numerical)
Jacobians:  $268$
Cyclic group of points:    no
Non-cyclic primes:   $2$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $1920$ $3686400$ $6321317760$ $11679989760000$ $21611482019529600$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $44$ $1990$ $79508$ $3416398$ $147008444$ $6321272470$ $271818611108$ $11688211063198$ $502592611936844$ $21611481725774950$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 268 curves (of which all are hyperelliptic):

  • $y^2=41 x^6+33 x^5+32 x^4+20 x^3+8 x^2+5 x+12$
  • $y^2=3 x^6+22 x^5+36 x^4+4 x^3+36 x^2+22 x+3$
  • $y^2=9 x^6+23 x^5+22 x^4+12 x^3+22 x^2+23 x+9$
  • $y^2=27 x^6+14 x^5+22 x^4+35 x^3+6 x^2+38 x+1$
  • $y^2=41 x^6+9 x^5+14 x^3+4 x+1$
  • $y^2=37 x^6+27 x^5+42 x^3+12 x+3$
  • $y^2=41 x^6+26 x^5+36 x^4+14 x^3+27 x^2+5 x+31$
  • $y^2=37 x^6+35 x^5+22 x^4+42 x^3+38 x^2+15 x+7$
  • $y^2=11 x^6+13 x^5+29 x^4+20 x^3+29 x^2+13 x+11$
  • $y^2=33 x^6+39 x^5+x^4+17 x^3+x^2+39 x+33$
  • $y^2=18 x^6+3 x^5+21 x^4+25 x^3+9 x^2+26 x+30$
  • $y^2=11 x^6+9 x^5+20 x^4+32 x^3+27 x^2+35 x+4$
  • $y^2=17 x^6+9 x^5+21 x^4+32 x^3+8 x^2+10 x+37$
  • $y^2=8 x^6+27 x^5+20 x^4+10 x^3+24 x^2+30 x+25$
  • $y^2=39 x^5+33 x^4+12 x^3+11 x^2+33 x$
  • $y^2=31 x^6+4 x^5+28 x^4+4 x^3+41 x^2+36 x+20$
  • $y^2=14 x^6+39 x^5+11 x^4+25 x^3+2 x^2+38 x+24$
  • $y^2=40 x^6+37 x^5+4 x^4+23 x^3+11 x^2+x+21$
  • $y^2=34 x^6+25 x^5+12 x^4+26 x^3+33 x^2+3 x+20$
  • $y^2=11 x^6+35 x^5+36 x^4+33 x^3+10 x^2+10 x+35$
  • and 248 more

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{43^{2}}$.

Endomorphism algebra over $\F_{43}$
The isogeny class factors as 1.43.ae $\times$ 1.43.e and its endomorphism algebra is a direct product of the endomorphism algebras for each isotypic factor. The endomorphism algebra for each factor is:
Endomorphism algebra over $\overline{\F}_{43}$
The base change of $A$ to $\F_{43^{2}}$ is 1.1849.cs 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-39}) \)$)$

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.43.ai_dy$2$(not in LMFDB)
2.43.i_dy$2$(not in LMFDB)
2.43.a_acs$4$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.43.ai_dy$2$(not in LMFDB)
2.43.i_dy$2$(not in LMFDB)
2.43.a_acs$4$(not in LMFDB)
2.43.ae_abb$6$(not in LMFDB)
2.43.e_abb$6$(not in LMFDB)