Properties

Label 2.29.a_d
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:  $1 + 3 x^{2} + 841 x^{4}$
Frobenius angles:  $\pm0.258235827353$, $\pm0.741764172647$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(\sqrt{55}, \sqrt{-61})\)
Galois group:  $C_2^2$
Jacobians:  $20$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $845$ $714025$ $594815780$ $502617192025$ $420707243796125$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $30$ $848$ $24390$ $710628$ $20511150$ $594808238$ $17249876310$ $500243644228$ $14507145975870$ $420707254292048$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 20 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 \(\Q(\sqrt{55}, \sqrt{-61})\).
Endomorphism algebra over $\overline{\F}_{29}$
The base change of $A$ to $\F_{29^{2}}$ is 1.841.d 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-3355}) \)$)$

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_ad$4$(not in LMFDB)