Properties

Label 2.79.u_jy
Base field $\F_{79}$
Dimension $2$
$p$-rank $2$
Ordinary yes
Supersingular no
Simple no
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:  $( 1 + 10 x + 79 x^{2} )^{2}$
  $1 + 20 x + 258 x^{2} + 1580 x^{3} + 6241 x^{4}$
Frobenius angles:  $\pm0.690177289346$, $\pm0.690177289346$
Angle rank:  $1$ (numerical)
Jacobians:  $87$

This isogeny class is not 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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $8100$ $39690000$ $241739388900$ $1517819264640000$ $9468381016694902500$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $100$ $6358$ $490300$ $38968318$ $3077090500$ $243085673878$ $19203924108700$ $1517108799431038$ $119851594892692900$ $9468276094353667798$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 87 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

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

Endomorphism algebra over $\F_{79}$
The isogeny class factors as 1.79.k 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-6}) \)$)$

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.au_jy$2$(not in LMFDB)
2.79.a_cg$2$(not in LMFDB)
2.79.ak_v$3$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.79.au_jy$2$(not in LMFDB)
2.79.a_cg$2$(not in LMFDB)
2.79.ak_v$3$(not in LMFDB)
2.79.a_acg$4$(not in LMFDB)
2.79.k_v$6$(not in LMFDB)