Properties

Label 2.29.b_abc
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:  $1 + x - 28 x^{2} + 29 x^{3} + 841 x^{4}$
Frobenius angles:  $\pm0.196263626344$, $\pm0.862930293010$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(\sqrt{-3}, \sqrt{-115})\)
Galois group:  $C_2^2$
Jacobians:  $14$
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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $844$ $661696$ $599074576$ $501356472064$ $420790525060924$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $31$ $785$ $24562$ $708849$ $20515211$ $594906086$ $17249717159$ $500247453889$ $14507134663258$ $420707208769625$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 14 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{29^{3}}$.

Endomorphism algebra over $\F_{29}$
The endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{-3}, \sqrt{-115})\).
Endomorphism algebra over $\overline{\F}_{29}$
The base change of $A$ to $\F_{29^{3}}$ is 1.24389.di 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-115}) \)$)$

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.ab_abc$2$(not in LMFDB)
2.29.ac_ch$3$(not in LMFDB)
2.29.a_cf$6$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.29.ab_abc$2$(not in LMFDB)
2.29.ac_ch$3$(not in LMFDB)
2.29.a_cf$6$(not in LMFDB)
2.29.c_ch$6$(not in LMFDB)
2.29.a_acf$12$(not in LMFDB)