Properties

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

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Invariants

Base field:  $\F_{5}$
Dimension:  $4$
L-polynomial:  $1 + 14 x^{2} + 94 x^{4} + 350 x^{6} + 625 x^{8}$
Frobenius angles:  $\pm0.329028055852$, $\pm0.437386669224$, $\pm0.562613330776$, $\pm0.670971944148$
Angle rank:  $2$ (numerical)
Number field:  8.0.206479360000.2
Galois group:  $D_4\times C_2$
Cyclic group of points:    no
Non-cyclic primes:   $2$

This isogeny class is simple but not geometrically 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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $1084$ $1175056$ $241741756$ $148921897216$ $95381250536764$

Point counts of the (virtual) curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $6$ $54$ $126$ $610$ $3126$ $15318$ $78126$ $391642$ $1953126$ $9768454$

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 $\F_{5^{2}}$.

Endomorphism algebra over $\F_{5}$
The endomorphism algebra of this simple isogeny class is 8.0.206479360000.2.
Endomorphism algebra over $\overline{\F}_{5}$
The base change of $A$ to $\F_{5^{2}}$ is 2.25.o_dq 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-34 +2 \sqrt{5}})\)$)$

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.a_ao_a_dq$4$(not in LMFDB)
4.5.ac_c_ag_o$8$(not in LMFDB)
4.5.c_c_g_o$8$(not in LMFDB)