Properties

Label 2.71.ae_acd
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

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Invariants

Base field:  $\F_{71}$
Dimension:  $2$
L-polynomial:  $1 - 4 x - 55 x^{2} - 284 x^{3} + 5041 x^{4}$
Frobenius angles:  $\pm0.0903857707042$, $\pm0.757052437371$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(\sqrt{-3}, \sqrt{-67})\)
Galois group:  $C_2^2$
Jacobians:  $24$
Isomorphism classes:  64
Cyclic group of points:    yes

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $4699$ $24787225$ $127537551376$ $645900774690025$ $3255100797623011579$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $68$ $4916$ $356336$ $25417476$ $1804150228$ $128100473678$ $9095126155708$ $645753513992836$ $45848501432044496$ $3255243553662029876$

Jacobians and polarizations

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

  • $y^2=41 x^6+16 x^5+18 x^4+32 x^3+5 x^2+39 x+10$
  • $y^2=25 x^6+68 x^5+56 x^4+17 x^3+67 x^2+21 x+47$
  • $y^2=27 x^6+2 x^5+43 x^4+15 x^3+28 x^2+36 x+60$
  • $y^2=60 x^6+32 x^5+26 x^4+48 x^3+31 x^2+21 x+58$
  • $y^2=51 x^6+54 x^5+67 x^4+33 x^3+42 x^2+38 x+47$
  • $y^2=56 x^6+31 x^5+12 x^4+40 x^3+28 x^2+10 x+15$
  • $y^2=37 x^6+56 x^5+53 x^4+15 x^3+12 x^2+35 x+34$
  • $y^2=23 x^6+55 x^5+2 x^4+44 x^3+52 x^2+20 x+43$
  • $y^2=15 x^6+22 x^5+11 x^4+9 x^3+28 x^2+13 x+3$
  • $y^2=57 x^6+66 x^5+24 x^4+14 x^3+42 x^2+43 x+66$
  • $y^2=70 x^6+14 x^5+57 x^4+6 x^3+6 x^2+17 x+42$
  • $y^2=8 x^6+63 x^5+57 x^4+51 x^3+19 x+63$
  • $y^2=64 x^6+60 x^5+20 x^4+21 x^3+31 x^2+58 x+5$
  • $y^2=17 x^6+63 x^5+38 x^4+49 x^2+28 x+34$
  • $y^2=53 x^6+28 x^5+34 x^4+11 x^3+29 x^2+15 x+64$
  • $y^2=39 x^6+36 x^5+x^4+12 x^3+2 x^2+13$
  • $y^2=15 x^6+24 x^5+56 x^4+10 x^3+x^2+37 x+46$
  • $y^2=69 x^6+17 x^5+36 x^4+37 x^3+66 x^2+52$
  • $y^2=19 x^6+33 x^5+15 x^4+58 x^3+39 x^2+20 x+67$
  • $y^2=5 x^6+16 x^5+47 x^4+11 x^3+59 x^2+50 x+19$
  • $y^2=68 x^6+63 x^5+20 x^4+67 x^3+26 x^2+4 x+23$
  • $y^2=7 x^6+26 x^5+64 x^4+46 x^2+5 x+3$
  • $y^2=37 x^6+60 x^5+61 x^4+38 x^3+58 x^2+26$
  • $y^2=42 x^6+40 x^5+36 x^4+49 x^3+19 x^2+39 x+11$

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 \(\Q(\sqrt{-3}, \sqrt{-67})\).
Endomorphism algebra over $\overline{\F}_{71}$
The base change of $A$ to $\F_{71^{3}}$ is 1.357911.abei 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-67}) \)$)$

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.e_acd$2$(not in LMFDB)
2.71.i_gc$3$(not in LMFDB)
2.71.ai_gc$6$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.71.e_acd$2$(not in LMFDB)
2.71.i_gc$3$(not in LMFDB)
2.71.ai_gc$6$(not in LMFDB)
2.71.a_ew$6$(not in LMFDB)
2.71.a_aew$12$(not in LMFDB)