Properties

Label 2.29.a_bh
Base field $\F_{29}$
Dimension $2$
$p$-rank $2$
Ordinary yes
Supersingular no
Simple no
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:  $( 1 - 5 x + 29 x^{2} )( 1 + 5 x + 29 x^{2} )$
  $1 + 33 x^{2} + 841 x^{4}$
Frobenius angles:  $\pm0.346328109963$, $\pm0.653671890037$
Angle rank:  $1$ (numerical)
Jacobians:  $38$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $875$ $765625$ $594776000$ $501087015625$ $420707238021875$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $30$ $908$ $24390$ $708468$ $20511150$ $594728678$ $17249876310$ $500248538788$ $14507145975870$ $420707242743548$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 38 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

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

Endomorphism algebra over $\F_{29}$
The isogeny class factors as 1.29.af $\times$ 1.29.f 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 $\overline{\F}_{29}$
The base change of $A$ to $\F_{29^{2}}$ is 1.841.bh 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-91}) \)$)$

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.29.ak_df$2$(not in LMFDB)
2.29.k_df$2$(not in LMFDB)
2.29.a_abh$4$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.29.ak_df$2$(not in LMFDB)
2.29.k_df$2$(not in LMFDB)
2.29.a_abh$4$(not in LMFDB)
2.29.af_ae$6$(not in LMFDB)
2.29.f_ae$6$(not in LMFDB)