Properties

Label 2.83.a_fu
Base field $\F_{83}$
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:  $\F_{83}$
Dimension:  $2$
L-polynomial:  $( 1 - 4 x + 83 x^{2} )( 1 + 4 x + 83 x^{2} )$
  $1 + 150 x^{2} + 6889 x^{4}$
Frobenius angles:  $\pm0.429548098763$, $\pm0.570451901237$
Angle rank:  $1$ (numerical)
Jacobians:  $425$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $7040$ $49561600$ $326940648320$ $2251464540160000$ $15516041182485219200$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $84$ $7190$ $571788$ $47440878$ $3939040644$ $326940923270$ $27136050989628$ $2252292269825758$ $186940255267540404$ $15516041177764584950$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 425 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.ae $\times$ 1.83.e 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.fu 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-79}) \)$)$

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.83.ai_ha$2$(not in LMFDB)
2.83.i_ha$2$(not in LMFDB)
2.83.a_afu$4$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.83.ai_ha$2$(not in LMFDB)
2.83.i_ha$2$(not in LMFDB)
2.83.a_afu$4$(not in LMFDB)
2.83.ae_acp$6$(not in LMFDB)
2.83.e_acp$6$(not in LMFDB)