Properties

Label 4.5.al_cj_ain_wd
Base field $\F_{5}$
Dimension $4$
$p$-rank $3$
Ordinary no
Supersingular no
Simple no
Geometrically simple no
Primitive yes
Principally polarizable yes
Contains a Jacobian no

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Invariants

Base field:  $\F_{5}$
Dimension:  $4$
L-polynomial:  $( 1 - 3 x + 5 x^{2} )( 1 - 8 x + 32 x^{2} - 85 x^{3} + 160 x^{4} - 200 x^{5} + 125 x^{6} )$
  $1 - 11 x + 61 x^{2} - 221 x^{3} + 575 x^{4} - 1105 x^{5} + 1525 x^{6} - 1375 x^{7} + 625 x^{8}$
Frobenius angles:  $\pm0.0657033817182$, $\pm0.238557099512$, $\pm0.265942140215$, $\pm0.475140873389$
Angle rank:  $4$ (numerical)

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

Newton polygon

$p$-rank:  $3$
Slopes:  $[0, 0, 0, 1/2, 1/2, 1, 1, 1]$

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $75$ $412425$ $285123600$ $156154415625$ $96915522862875$

Point counts of the (virtual) curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $-5$ $27$ $145$ $643$ $3175$ $15747$ $77555$ $387363$ $1948690$ $9773827$

Jacobians and polarizations

This isogeny class is principally polarizable, but does not contain a Jacobian.

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{5}$.

Endomorphism algebra over $\F_{5}$
The isogeny class factors as 1.5.ad $\times$ 3.5.ai_bg_adh 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 is a list of all twists of this isogeny class.

TwistExtension degreeCommon base change
4.5.af_n_abd_cn$2$(not in LMFDB)
4.5.f_n_bd_cn$2$(not in LMFDB)
4.5.l_cj_in_wd$2$(not in LMFDB)