Properties

Label 2.29.a_bi
Base field $\F_{29}$
Dimension $2$
$p$-rank $2$
Ordinary yes
Supersingular no
Simple yes
Geometrically simple no
Primitive yes
Principally polarizable yes
Contains a Jacobian yes

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Invariants

Base field:  $\F_{29}$
Dimension:  $2$
L-polynomial:  $1 + 34 x^{2} + 841 x^{4}$
Frobenius angles:  $\pm0.349689715424$, $\pm0.650310284576$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(\sqrt{6}, \sqrt{-23})\)
Galois group:  $C_2^2$
Jacobians:  $84$
Cyclic group of points:    no
Non-cyclic primes:   $2$

This isogeny class is simple but not 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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $876$ $767376$ $594776844$ $500992164864$ $420707233700076$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $30$ $910$ $24390$ $708334$ $20511150$ $594730366$ $17249876310$ $500248688734$ $14507145975870$ $420707234099950$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 84 curves (of which all are hyperelliptic):

  • $y^2=18 x^6+7 x^5+18 x^4+19 x^3+5 x^2+19 x+15$
  • $y^2=7 x^6+14 x^5+7 x^4+9 x^3+10 x^2+9 x+1$
  • $y^2=9 x^6+6 x^5+12 x^4+24 x^3+22 x^2+13 x+23$
  • $y^2=18 x^6+12 x^5+24 x^4+19 x^3+15 x^2+26 x+17$
  • $y^2=9 x^5+24 x^4+2 x^3+19 x^2+26 x+9$
  • $y^2=18 x^5+19 x^4+4 x^3+9 x^2+23 x+18$
  • $y^2=10 x^6+7 x^5+12 x^4+20 x^3+22 x^2+5 x+8$
  • $y^2=20 x^6+14 x^5+24 x^4+11 x^3+15 x^2+10 x+16$
  • $y^2=20 x^5+26 x^4+8 x^3+5 x^2+19 x+1$
  • $y^2=11 x^5+23 x^4+16 x^3+10 x^2+9 x+2$
  • $y^2=17 x^6+16 x^5+15 x^4+17 x^3+25 x^2+9 x+25$
  • $y^2=21 x^6+15 x^5+12 x^4+13 x^3+20 x^2+3 x+7$
  • $y^2=10 x^6+26 x^5+25 x^4+13 x^3+4 x^2+16 x+19$
  • $y^2=20 x^6+23 x^5+21 x^4+26 x^3+8 x^2+3 x+9$
  • $y^2=9 x^6+6 x^5+6 x^4+19 x^3+3 x^2+2 x+16$
  • $y^2=18 x^6+12 x^5+12 x^4+9 x^3+6 x^2+4 x+3$
  • $y^2=8 x^6+13 x^5+18 x^4+26 x^3+22 x^2+23 x+23$
  • $y^2=16 x^6+17 x^5+6 x^4+16 x^3+17 x+8$
  • $y^2=3 x^6+5 x^5+12 x^4+3 x^3+5 x+16$
  • $y^2=23 x^6+26 x^4+4 x^3+4 x^2+11$
  • and 64 more

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{29^{2}}$.

Endomorphism algebra over $\F_{29}$
The endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{6}, \sqrt{-23})\).
Endomorphism algebra over $\overline{\F}_{29}$
The base change of $A$ to $\F_{29^{2}}$ is 1.841.bi 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-138}) \)$)$

Base change

This is a primitive isogeny class.

Twists

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

TwistExtension degreeCommon base change
2.29.a_abi$4$(not in LMFDB)