Invariants
Base field: | $\F_{2^{4}}$ |
Dimension: | $2$ |
L-polynomial: | $( 1 - 4 x )^{4}$ |
$1 - 16 x + 96 x^{2} - 256 x^{3} + 256 x^{4}$ | |
Frobenius angles: | $0$, $0$, $0$, $0$ |
Angle rank: | $0$ (numerical) |
Jacobians: | $1$ |
This isogeny class is not 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: | $[1/2, 1/2, 1/2, 1/2]$ |
Point counts
Point counts of the abelian variety
$r$ | $1$ | $2$ | $3$ | $4$ | $5$ |
---|---|---|---|---|---|
$A(\F_{q^r})$ | $81$ | $50625$ | $15752961$ | $4228250625$ | $1095222947841$ |
$r$ | $1$ | $2$ | $3$ | $4$ | $5$ | $6$ | $7$ | $8$ | $9$ | $10$ |
---|---|---|---|---|---|---|---|---|---|---|
$C(\F_{q^r})$ | $1$ | $193$ | $3841$ | $64513$ | $1044481$ | $16760833$ | $268369921$ | $4294705153$ | $68718428161$ | $1099507433473$ |
Jacobians and polarizations
This isogeny class contains the Jacobian of 1 curve (which is hyperelliptic), and hence is principally polarizable:
- $y^2+y=x^5+a^3+a^2+a$
Decomposition and endomorphism algebra
All geometric endomorphisms are defined over $\F_{2^{4}}$.
Endomorphism algebra over $\F_{2^{4}}$The isogeny class factors as 1.16.ai 2 and its endomorphism algebra is $\mathrm{M}_{2}(B)$, where $B$ is the quaternion algebra over \(\Q\) ramified at $2$ and $\infty$. |
Base change
This isogeny class is not primitive. It is a base change from the following isogeny classes over subfields of $\F_{2^{4}}$.
Subfield | Primitive Model |
$\F_{2}$ | 2.2.a_ae |
$\F_{2}$ | 2.2.a_e |