Properties

Label 1.125.a
Base field $\F_{5^{3}}$
Dimension $1$
$p$-rank $0$
Ordinary no
Supersingular yes
Simple yes
Geometrically simple yes
Primitive no
Principally polarizable yes
Contains a Jacobian yes

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Invariants

Base field:  $\F_{5^{3}}$
Dimension:  $1$
L-polynomial:  $1 + 125 x^{2}$
Frobenius angles:  $\pm0.5$
Angle rank:  $0$ (numerical)
Number field:  \(\Q(\sqrt{-5}) \)
Galois group:  $C_2$
Jacobians:  $2$

This isogeny class is simple and geometrically simple, not primitive, not ordinary, and supersingular. It is principally polarizable and contains a Jacobian.

Newton polygon

This isogeny class is supersingular.

$p$-rank:  $0$
Slopes:  $[1/2, 1/2]$

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $126$ $15876$ $1953126$ $244109376$ $30517578126$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $126$ $15876$ $1953126$ $244109376$ $30517578126$ $3814701171876$ $476837158203126$ $59604644287109376$ $7450580596923828126$ $931322574676513671876$

Jacobians and polarizations

This isogeny class contains the Jacobians of 2 curves (of which all are hyperelliptic), and hence is principally polarizable:

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{5^{6}}$.

Endomorphism algebra over $\F_{5^{3}}$
The endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{-5}) \).
Endomorphism algebra over $\overline{\F}_{5^{3}}$
The base change of $A$ to $\F_{5^{6}}$ is the simple isogeny class 1.15625.jq and its endomorphism algebra is the quaternion algebra over \(\Q\) ramified at $5$ and $\infty$.

Base change

This isogeny class is not primitive. It is a base change from the following isogeny classes over subfields of $\F_{5^{3}}$.

SubfieldPrimitive Model
$\F_{5}$1.5.a

Twists

This isogeny class has no twists.