Properties

Label 2.73.a_ab
Base field $\F_{73}$
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:  $\F_{73}$
Dimension:  $2$
L-polynomial:  $1 - x^{2} + 5329 x^{4}$
Frobenius angles:  $\pm0.248909889127$, $\pm0.751090110873$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(\sqrt{3}, \sqrt{-145})\)
Galois group:  $C_2^2$
Jacobians:  $126$
Isomorphism classes:  336

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $5329$ $28398241$ $151334242276$ $807065542392201$ $4297625829561593089$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $74$ $5328$ $389018$ $28419556$ $2073071594$ $151334258262$ $11047398519098$ $806459978343748$ $58871586708267914$ $4297625829419628528$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 126 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{73^{2}}$.

Endomorphism algebra over $\F_{73}$
The endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{3}, \sqrt{-145})\).
Endomorphism algebra over $\overline{\F}_{73}$
The base change of $A$ to $\F_{73^{2}}$ is 1.5329.ab 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-435}) \)$)$

Base change

This is a primitive isogeny class.

Twists

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

TwistExtension degreeCommon base change
2.73.a_b$4$(not in LMFDB)
2.73.av_im$12$(not in LMFDB)
2.73.v_im$12$(not in LMFDB)