Properties

Label 2.83.j_gk
Base field $\F_{83}$
Dimension $2$
$p$-rank $1$
Ordinary no
Supersingular no
Simple no
Geometrically simple no
Primitive yes
Principally polarizable yes
Contains a Jacobian yes

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Invariants

Base field:  $\F_{83}$
Dimension:  $2$
L-polynomial:  $( 1 + 83 x^{2} )( 1 + 9 x + 83 x^{2} )$
  $1 + 9 x + 166 x^{2} + 747 x^{3} + 6889 x^{4}$
Frobenius angles:  $\pm0.5$, $\pm0.664443457247$
Angle rank:  $1$ (numerical)
Jacobians:  $336$

This isogeny class is not simple, primitive, not ordinary, and not supersingular. It is principally polarizable and contains a Jacobian.

Newton polygon

$p$-rank:  $1$
Slopes:  $[0, 1/2, 1/2, 1]$

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $7812$ $49215600$ $326076973488$ $2251949350392000$ $15516303216128532972$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $93$ $7141$ $570276$ $47451097$ $3939107163$ $326940374374$ $27136055751681$ $2252292189197233$ $186940254404516508$ $15516041198537238661$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 336 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{83^{2}}$.

Endomorphism algebra over $\F_{83}$
The isogeny class factors as 1.83.a $\times$ 1.83.j and its endomorphism algebra is a direct product of the endomorphism algebras for each isotypic factor. The endomorphism algebra for each factor is:
Endomorphism algebra over $\overline{\F}_{83}$
The base change of $A$ to $\F_{83^{2}}$ is 1.6889.dh $\times$ 1.6889.gk. The endomorphism algebra for each factor is:

Base change

This is a primitive isogeny class.

Twists

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

TwistExtension degreeCommon base change
2.83.aj_gk$2$(not in LMFDB)