Invariants
Base field: | $\F_{2^{4}}$ |
Dimension: | $2$ |
L-polynomial: | $( 1 - 4 x )^{2}( 1 - 4 x + 16 x^{2} )$ |
$1 - 12 x + 64 x^{2} - 192 x^{3} + 256 x^{4}$ | |
Frobenius angles: | $0$, $0$, $\pm0.333333333333$ |
Angle rank: | $0$ (numerical) |
Jacobians: | $0$ |
This isogeny class is not simple, primitive, not ordinary, and supersingular. It is principally polarizable.
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
$r$ | $1$ | $2$ | $3$ | $4$ | $5$ |
---|---|---|---|---|---|
$A(\F_{q^r})$ | $117$ | $61425$ | $16769025$ | $4278189825$ | $1096294593537$ |
Point counts of the (virtual) curve
$r$ | $1$ | $2$ | $3$ | $4$ | $5$ | $6$ | $7$ | $8$ | $9$ | $10$ |
---|---|---|---|---|---|---|---|---|---|---|
$C(\F_{q^r})$ | $5$ | $241$ | $4097$ | $65281$ | $1045505$ | $16760833$ | $268386305$ | $4294901761$ | $68719476737$ | $1099510579201$ |
Jacobians and polarizations
This isogeny class is principally polarizable, but does not contain a Jacobian.
Decomposition and endomorphism algebra
All geometric endomorphisms are defined over $\F_{2^{24}}$.
Endomorphism algebra over $\F_{2^{4}}$The isogeny class factors as 1.16.ai $\times$ 1.16.ae and its endomorphism algebra is a direct product of the endomorphism algebras for each isotypic factor. The endomorphism algebra for each factor is:
|
The base change of $A$ to $\F_{2^{24}}$ is 1.16777216.amdc 2 and its endomorphism algebra is $\mathrm{M}_{2}(B)$, where $B$ is the quaternion algebra over \(\Q\) ramified at $2$ and $\infty$. |
- Endomorphism algebra over $\F_{2^{8}}$
The base change of $A$ to $\F_{2^{8}}$ is 1.256.abg $\times$ 1.256.q. The endomorphism algebra for each factor is: - 1.256.abg : the quaternion algebra over \(\Q\) ramified at $2$ and $\infty$.
- 1.256.q : \(\Q(\sqrt{-3}) \).
- Endomorphism algebra over $\F_{2^{12}}$
The base change of $A$ to $\F_{2^{12}}$ is 1.4096.aey $\times$ 1.4096.ey. The endomorphism algebra for each factor is: - 1.4096.aey : the quaternion algebra over \(\Q\) ramified at $2$ and $\infty$.
- 1.4096.ey : the quaternion algebra over \(\Q\) ramified at $2$ and $\infty$.
Base change
This is a primitive isogeny class.