Properties

Label 2.71.g_abj
Base field $\F_{71}$
Dimension $2$
$p$-rank $2$
Ordinary yes
Supersingular no
Simple yes
Geometrically simple no
Primitive yes
Principally polarizable yes
Contains a Jacobian yes

Related objects

Downloads

Learn more

Invariants

Base field:  $\F_{71}$
Dimension:  $2$
L-polynomial:  $1 + 6 x - 35 x^{2} + 426 x^{3} + 5041 x^{4}$
Frobenius angles:  $\pm0.282538109229$, $\pm0.949204775895$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(\sqrt{-3}, \sqrt{-62})\)
Galois group:  $C_2^2$
Jacobians:  $24$
Isomorphism classes:  136
Cyclic group of points:    no
Non-cyclic primes:   $7$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $5439$ $24883425$ $128862332676$ $645782832246825$ $3255392090968854879$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $78$ $4936$ $360036$ $25412836$ $1804311678$ $128099459878$ $9095116785378$ $645753481754116$ $45848500833380796$ $3255243554178992776$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 24 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{71^{3}}$.

Endomorphism algebra over $\F_{71}$
The endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{-3}, \sqrt{-62})\).
Endomorphism algebra over $\overline{\F}_{71}$
The base change of $A$ to $\F_{71^{3}}$ is 1.357911.bow 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-62}) \)$)$

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.71.ag_abj$2$(not in LMFDB)
2.71.am_gw$3$(not in LMFDB)
2.71.a_ec$6$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.71.ag_abj$2$(not in LMFDB)
2.71.am_gw$3$(not in LMFDB)
2.71.a_ec$6$(not in LMFDB)
2.71.m_gw$6$(not in LMFDB)
2.71.a_aec$12$(not in LMFDB)