Properties

Label 2.163.abs_bfe
Base field $\F_{163}$
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:  $\F_{163}$
Dimension:  $2$
L-polynomial:  $( 1 - 22 x + 163 x^{2} )^{2}$
  $1 - 44 x + 810 x^{2} - 7172 x^{3} + 26569 x^{4}$
Frobenius angles:  $\pm0.169471200781$, $\pm0.169471200781$
Angle rank:  $1$ (numerical)
Jacobians:  $32$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $20164$ $697593744$ $18756331016164$ $498351193239684096$ $13239774480732511599364$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $120$ $26254$ $4330968$ $705968110$ $115064820840$ $18755386876798$ $3057125425570056$ $498311415554219614$ $81224760530998111704$ $13239635966753852127214$

Jacobians and polarizations

This isogeny class contains the Jacobians of 32 curves (of which all are hyperelliptic), and hence is principally polarizable:

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{163}$.

Endomorphism algebra over $\F_{163}$
The isogeny class factors as 1.163.aw 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-42}) \)$)$

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.163.a_agc$2$(not in LMFDB)
2.163.bs_bfe$2$(not in LMFDB)
2.163.w_mj$3$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.163.a_agc$2$(not in LMFDB)
2.163.bs_bfe$2$(not in LMFDB)
2.163.w_mj$3$(not in LMFDB)
2.163.a_gc$4$(not in LMFDB)
2.163.aw_mj$6$(not in LMFDB)