Properties

Label 2.11.af_o
Base field $\F_{11}$
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:  $\F_{11}$
Dimension:  $2$
L-polynomial:  $1 - 5 x + 14 x^{2} - 55 x^{3} + 121 x^{4}$
Frobenius angles:  $\pm0.105104110453$, $\pm0.561562556214$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(\sqrt{-3}, \sqrt{-19})\)
Galois group:  $C_2^2$
Jacobians:  $7$
Isomorphism classes:  6

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $76$ $14896$ $1669264$ $210986944$ $26054551876$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $7$ $125$ $1252$ $14409$ $161777$ $1773686$ $19484507$ $214383889$ $2358139132$ $25937628125$

Jacobians and polarizations

This isogeny class contains the Jacobians of 7 curves (of which all are hyperelliptic), and hence is principally polarizable:

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{11^{3}}$.

Endomorphism algebra over $\F_{11}$
The endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{-3}, \sqrt{-19})\).
Endomorphism algebra over $\overline{\F}_{11}$
The base change of $A$ to $\F_{11^{3}}$ is 1.1331.abo 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-19}) \)$)$

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.11.f_o$2$2.121.d_aei
2.11.k_bv$3$(not in LMFDB)
2.11.ak_bv$6$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.11.f_o$2$2.121.d_aei
2.11.k_bv$3$(not in LMFDB)
2.11.ak_bv$6$(not in LMFDB)
2.11.a_ad$6$(not in LMFDB)
2.11.f_o$6$(not in LMFDB)
2.11.a_d$12$(not in LMFDB)