Properties

Label 2.71.ag_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

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Invariants

Base field:  $\F_{71}$
Dimension:  $2$
L-polynomial:  $1 - 6 x - 35 x^{2} - 426 x^{3} + 5041 x^{4}$
Frobenius angles:  $\pm0.0507952241045$, $\pm0.717461890771$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(\sqrt{-3}, \sqrt{-62})\)
Galois group:  $C_2^2$
Jacobians:  $24$
Cyclic group of points:    no
Non-cyclic primes:   $5$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $4575$ $24883425$ $127341922500$ $645782832246825$ $3255095020997589375$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $66$ $4936$ $355788$ $25412836$ $1804147026$ $128099459878$ $9095123531406$ $645753481754116$ $45848500603517268$ $3255243554178992776$

Jacobians and polarizations

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

  • $y^2=56 x^6+55 x^5+70 x^4+48 x^3+4 x^2+66 x+34$
  • $y^2=19 x^6+9 x^5+69 x^4+70 x^3+25 x^2+34 x+19$
  • $y^2=53 x^6+51 x^5+42 x^4+4 x^3+3 x^2+11 x+66$
  • $y^2=22 x^6+26 x^5+41 x^4+30 x^3+28 x^2+35 x+22$
  • $y^2=50 x^6+38 x^5+67 x^4+18 x^3+59 x^2+49 x+50$
  • $y^2=27 x^6+62 x^5+38 x^4+34 x^3+4 x^2+15 x+34$
  • $y^2=2 x^6+35 x^5+44 x^4+4 x^3+41 x^2+48 x+2$
  • $y^2=54 x^6+24 x^5+43 x^4+9 x^3+23 x^2+16 x+54$
  • $y^2=14 x^6+30 x^5+41 x^4+46 x^3+43 x^2+47 x+30$
  • $y^2=27 x^6+26 x^5+20 x^4+46 x^3+52 x^2+30 x+52$
  • $y^2=12 x^6+64 x^5+x^4+49 x^3+37 x^2+11 x+64$
  • $y^2=56 x^6+9 x^5+11 x^4+40 x^3+25 x^2+43 x+56$
  • $y^2=14 x^6+8 x^5+x^4+18 x^3+8 x^2+61 x+27$
  • $y^2=40 x^6+67 x^5+51 x^4+25 x^3+32 x^2+31 x+40$
  • $y^2=49 x^6+41 x^5+54 x^4+38 x^3+16 x^2+40 x+49$
  • $y^2=48 x^6+26 x^5+32 x^4+52 x^3+29 x^2+x+16$
  • $y^2=34 x^6+66 x^5+10 x^4+58 x^3+39 x^2+33 x+46$
  • $y^2=10 x^6+9 x^5+58 x^4+47 x^3+36 x^2+20 x+41$
  • $y^2=45 x^6+6 x^5+7 x^4+50 x^3+6 x^2+66 x+6$
  • $y^2=27 x^6+35 x^5+58 x^4+38 x^3+64 x^2+20 x+28$
  • $y^2=39 x^6+36 x^5+49 x^4+44 x^3+14 x^2+24 x+24$
  • $y^2=58 x^6+42 x^5+56 x^4+57 x^3+61 x^2+52 x+42$
  • $y^2=44 x^6+17 x^5+60 x^4+25 x^3+63 x^2+57 x+6$
  • $y^2=65 x^6+27 x^5+11 x^4+51 x^3+56 x^2+62 x+41$

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.abow 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.g_abj$2$(not in LMFDB)
2.71.m_gw$3$(not in LMFDB)
2.71.am_gw$6$(not in LMFDB)

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

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