Invariants
Base field: | $\F_{7}$ |
Dimension: | $2$ |
L-polynomial: | $1 + 12 x^{2} + 49 x^{4}$ |
Frobenius angles: | $\pm0.413881335739$, $\pm0.586118664261$ |
Angle rank: | $1$ (numerical) |
Number field: | \(\Q(\sqrt{2}, \sqrt{-13})\) |
Galois group: | $C_2^2$ |
Jacobians: | $5$ |
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
$r$ | $1$ | $2$ | $3$ | $4$ | $5$ |
---|---|---|---|---|---|
$A(\F_{q^r})$ | $62$ | $3844$ | $117614$ | $5550736$ | $282444782$ |
$r$ | $1$ | $2$ | $3$ | $4$ | $5$ | $6$ | $7$ | $8$ | $9$ | $10$ |
---|---|---|---|---|---|---|---|---|---|---|
$C(\F_{q^r})$ | $8$ | $74$ | $344$ | $2310$ | $16808$ | $117578$ | $823544$ | $5770174$ | $40353608$ | $282414314$ |
Jacobians and polarizations
This isogeny class is principally polarizable and contains the Jacobians of 5 curves (of which all are hyperelliptic):
- $y^2=5 x^6+3 x^5+3 x^4+6 x^3+2 x^2+6 x$
- $y^2=x^6+2 x^5+2 x^4+4 x^3+6 x^2+4 x$
- $y^2=6 x^6+2 x+1$
- $y^2=4 x^6+6 x+3$
- $y^2=3 x^6+x^5+5 x+4$
Decomposition and endomorphism algebra
All geometric endomorphisms are defined over $\F_{7^{2}}$.
Endomorphism algebra over $\F_{7}$The endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{2}, \sqrt{-13})\). |
The base change of $A$ to $\F_{7^{2}}$ is 1.49.m 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-13}) \)$)$ |
Base change
This is a primitive isogeny class.
Twists
Below is a list of all twists of this isogeny class.
Twist | Extension degree | Common base change |
---|---|---|
2.7.a_am | $4$ | (not in LMFDB) |
2.7.ac_c | $8$ | (not in LMFDB) |
2.7.c_c | $8$ | (not in LMFDB) |