Properties

Label 2.89.g_fi
Base field $\F_{89}$
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:  $\F_{89}$
Dimension:  $2$
L-polynomial:  $( 1 - 4 x + 89 x^{2} )( 1 + 10 x + 89 x^{2} )$
  $1 + 6 x + 138 x^{2} + 534 x^{3} + 7921 x^{4}$
Frobenius angles:  $\pm0.432002453901$, $\pm0.677807684489$
Angle rank:  $2$ (numerical)
Jacobians:  $280$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $8600$ $64672000$ $496511514200$ $3936548423680000$ $31181273689921703000$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $96$ $8162$ $704304$ $62741598$ $5583979536$ $496980313922$ $44231357405184$ $3936588853250878$ $350356401470598336$ $31181719932544749602$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 280 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{89}$.

Endomorphism algebra over $\F_{89}$
The isogeny class factors as 1.89.ae $\times$ 1.89.k and its endomorphism algebra is a direct product of the endomorphism algebras for each isotypic factor. The endomorphism algebra for each factor is:

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.89.ao_ik$2$(not in LMFDB)
2.89.ag_fi$2$(not in LMFDB)
2.89.o_ik$2$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.89.ao_ik$2$(not in LMFDB)
2.89.ag_fi$2$(not in LMFDB)
2.89.o_ik$2$(not in LMFDB)
2.89.au_ji$4$(not in LMFDB)
2.89.am_ek$4$(not in LMFDB)
2.89.m_ek$4$(not in LMFDB)
2.89.u_ji$4$(not in LMFDB)