Properties

Label 2.83.a_be
Base field $\F_{83}$
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:  $\F_{83}$
Dimension:  $2$
L-polynomial:  $1 + 30 x^{2} + 6889 x^{4}$
Frobenius angles:  $\pm0.278921858379$, $\pm0.721078141621$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(i, \sqrt{34})\)
Galois group:  $C_2^2$
Jacobians:  $498$
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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $6920$ $47886400$ $326939780360$ $2253514829440000$ $15516041193418886600$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $84$ $6950$ $571788$ $47484078$ $3939040644$ $326939187350$ $27136050989628$ $2252292090286558$ $186940255267540404$ $15516041199631919750$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 498 curves (of which all are hyperelliptic):

  • $y^2=26 x^6+53 x^5+44 x^4+7 x^3+73 x^2+38 x+33$
  • $y^2=52 x^6+23 x^5+5 x^4+14 x^3+63 x^2+76 x+66$
  • $y^2=30 x^6+45 x^5+20 x^4+60 x^3+40 x^2+49 x+25$
  • $y^2=60 x^6+7 x^5+40 x^4+37 x^3+80 x^2+15 x+50$
  • $y^2=9 x^6+10 x^5+2 x^4+58 x^3+47 x^2+38 x+8$
  • $y^2=69 x^6+9 x^5+63 x^4+70 x^3+66 x^2+25 x+6$
  • $y^2=23 x^6+3 x^5+42 x^4+2 x^3+8 x^2+19 x+81$
  • $y^2=34 x^6+48 x^5+76 x^4+13 x^3+38 x^2+56 x+12$
  • $y^2=68 x^6+13 x^5+69 x^4+26 x^3+76 x^2+29 x+24$
  • $y^2=41 x^6+82 x^5+6 x^4+75 x^3+28 x^2+71 x+18$
  • $y^2=82 x^6+81 x^5+12 x^4+67 x^3+56 x^2+59 x+36$
  • $y^2=60 x^6+15 x^5+77 x^4+19 x^3+15 x^2+51 x+15$
  • $y^2=26 x^6+47 x^5+24 x^4+57 x^3+29 x^2+26 x+5$
  • $y^2=68 x^6+13 x^5+60 x^4+12 x^3+8 x^2+11 x+73$
  • $y^2=53 x^6+26 x^5+37 x^4+24 x^3+16 x^2+22 x+63$
  • $y^2=78 x^6+22 x^5+x^4+25 x^3+36 x^2+39 x+55$
  • $y^2=73 x^6+44 x^5+2 x^4+50 x^3+72 x^2+78 x+27$
  • $y^2=23 x^6+55 x^5+22 x^4+57 x^3+61 x^2+41 x+26$
  • $y^2=46 x^6+27 x^5+44 x^4+31 x^3+39 x^2+82 x+52$
  • $y^2=32 x^6+53 x^5+65 x^4+26 x^3+53 x^2+55 x+16$
  • and 478 more

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{83^{2}}$.

Endomorphism algebra over $\F_{83}$
The endomorphism algebra of this simple isogeny class is \(\Q(i, \sqrt{34})\).
Endomorphism algebra over $\overline{\F}_{83}$
The base change of $A$ to $\F_{83^{2}}$ is 1.6889.be 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-34}) \)$)$

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.83.abc_ny$4$(not in LMFDB)
2.83.a_abe$4$(not in LMFDB)
2.83.bc_ny$4$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.83.abc_ny$4$(not in LMFDB)
2.83.a_abe$4$(not in LMFDB)
2.83.bc_ny$4$(not in LMFDB)
2.83.ao_ej$12$(not in LMFDB)
2.83.o_ej$12$(not in LMFDB)