Properties

Label 2.29.a_u
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:  $1 + 20 x^{2} + 841 x^{4}$
Frobenius angles:  $\pm0.306031309296$, $\pm0.693968690704$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(\sqrt{38}, \sqrt{-78})\)
Galois group:  $C_2^2$
Jacobians:  $36$
Isomorphism classes:  48

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $862$ $743044$ $594780862$ $502062942096$ $420707273588302$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $30$ $882$ $24390$ $709846$ $20511150$ $594738402$ $17249876310$ $500245955038$ $14507145975870$ $420707313876402$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 36 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 endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{38}, \sqrt{-78})\).
Endomorphism algebra over $\overline{\F}_{29}$
The base change of $A$ to $\F_{29^{2}}$ is 1.841.u 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-741}) \)$)$

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_au$4$(not in LMFDB)