Properties

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

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Invariants

Base field:  $\F_{5}$
Dimension:  $4$
L-polynomial:  $( 1 - 2 x + 8 x^{2} - 10 x^{3} + 25 x^{4} )^{2}$
  $1 - 4 x + 20 x^{2} - 52 x^{3} + 154 x^{4} - 260 x^{5} + 500 x^{6} - 500 x^{7} + 625 x^{8}$
Frobenius angles:  $\pm0.290805673663$, $\pm0.290805673663$, $\pm0.552340175673$, $\pm0.552340175673$
Angle rank:  $2$ (numerical)
Cyclic group of points:    no
Non-cyclic primes:   $2, 11$

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

Newton polygon

This isogeny class is ordinary.

$p$-rank:  $4$
Slopes:  $[0, 0, 0, 0, 1, 1, 1, 1]$

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $484$ $1024144$ $286218724$ $154178734336$ $101597166929764$

Point counts of the (virtual) curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $2$ $50$ $146$ $634$ $3322$ $15554$ $75994$ $388698$ $1960706$ $9776690$

Jacobians and polarizations

This isogeny class is principally polarizable and contains no Jacobian of a hyperelliptic curve, but it is unknown whether it contains a Jacobian of a non-hyperelliptic curve.

Decomposition and endomorphism algebra

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

Endomorphism algebra over $\F_{5}$
The isogeny class factors as 2.5.ac_i 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-16 -2 \sqrt{3}})\)$)$

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
4.5.a_m_a_cw$2$(not in LMFDB)
4.5.e_u_ca_fy$2$(not in LMFDB)
4.5.c_ae_ae_t$3$(not in LMFDB)

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

TwistExtension degreeCommon base change
4.5.a_m_a_cw$2$(not in LMFDB)
4.5.e_u_ca_fy$2$(not in LMFDB)
4.5.c_ae_ae_t$3$(not in LMFDB)
4.5.a_am_a_cw$4$(not in LMFDB)
4.5.ac_ae_e_t$6$(not in LMFDB)
4.5.ag_y_acu_gx$12$(not in LMFDB)
4.5.g_y_cu_gx$12$(not in LMFDB)