Properties

Label 2.79.a_agc
Base field $\F_{79}$
Dimension $2$
$p$-rank $0$
Ordinary no
Supersingular yes
Simple yes
Geometrically simple no
Primitive yes
Principally polarizable yes
Contains a Jacobian yes

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Invariants

Base field:  $\F_{79}$
Dimension:  $2$
L-polynomial:  $( 1 - 79 x^{2} )^{2}$
  $1 - 158 x^{2} + 6241 x^{4}$
Frobenius angles:  $0$, $0$, $1$, $1$
Angle rank:  $0$ (numerical)
Number field:  \(\Q(\sqrt{79}) \)
Galois group:  $C_2$
Jacobians:  $15$

This isogeny class is simple but not geometrically simple, 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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $6084$ $37015056$ $243086469444$ $1516136693760000$ $9468276076472734404$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $80$ $5926$ $493040$ $38925118$ $3077056400$ $243085483366$ $19203908986160$ $1517108654106238$ $119851595982618320$ $9468276070318621606$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 15 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{79^{2}}$.

Endomorphism algebra over $\F_{79}$
The endomorphism algebra of this simple isogeny class is the quaternion algebra over \(\Q(\sqrt{79}) \) ramified at both real infinite places.
Endomorphism algebra over $\overline{\F}_{79}$
The base change of $A$ to $\F_{79^{2}}$ is 1.6241.agc 2 and its endomorphism algebra is $\mathrm{M}_{2}(B)$, where $B$ is the quaternion algebra over \(\Q\) ramified at $79$ and $\infty$.

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.79.a_db$3$(not in LMFDB)
2.79.a_gc$4$(not in LMFDB)
2.79.a_db$6$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.79.a_db$3$(not in LMFDB)
2.79.a_gc$4$(not in LMFDB)
2.79.a_db$6$(not in LMFDB)
2.79.a_a$8$(not in LMFDB)
2.79.a_adb$12$(not in LMFDB)