Properties

Label 2.67.a_di
Base field $\F_{67}$
Dimension $2$
$p$-rank $2$
Ordinary yes
Supersingular no
Simple yes
Geometrically simple no
Primitive yes
Principally polarizable yes
Contains a Jacobian yes

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Invariants

Base field:  $\F_{67}$
Dimension:  $2$
L-polynomial:  $1 + 86 x^{2} + 4489 x^{4}$
Frobenius angles:  $\pm0.360904175595$, $\pm0.639095824405$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(\sqrt{3}, \sqrt{-55})\)
Galois group:  $C_2^2$
Jacobians:  $356$
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 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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $4576$ $20939776$ $90457860064$ $406131478511616$ $1822837803644736736$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $68$ $4662$ $300764$ $20154286$ $1350125108$ $90457337958$ $6060711605324$ $406067753155678$ $27206534396294948$ $1822837802737712022$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 356 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{67^{2}}$.

Endomorphism algebra over $\F_{67}$
The endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{3}, \sqrt{-55})\).
Endomorphism algebra over $\overline{\F}_{67}$
The base change of $A$ to $\F_{67^{2}}$ is 1.4489.di 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-165}) \)$)$

Base change

This is a primitive isogeny class.

Twists

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

TwistExtension degreeCommon base change
2.67.a_adi$4$(not in LMFDB)
2.67.am_el$12$(not in LMFDB)
2.67.m_el$12$(not in LMFDB)