Properties

Label 2.89.a_abi
Base field $\F_{89}$
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:  $\F_{89}$
Dimension:  $2$
L-polynomial:  $1 - 34 x^{2} + 7921 x^{4}$
Frobenius angles:  $\pm0.219411653755$, $\pm0.780588346245$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(i, \sqrt{53})\)
Galois group:  $C_2^2$
Jacobians:  $681$
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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $7888$ $62220544$ $496982059600$ $3938432011997184$ $31181719920811202128$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $90$ $7854$ $704970$ $62771614$ $5584059450$ $496982828238$ $44231334895530$ $3936588625313854$ $350356403707485210$ $31181719911656220654$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 681 curves (of which all are hyperelliptic):

  • $y^2=25 x^6+16 x^5+4 x^4+5 x^3+6 x^2+20 x+63$
  • $y^2=75 x^6+48 x^5+12 x^4+15 x^3+18 x^2+60 x+11$
  • $y^2=27 x^6+31 x^5+69 x^4+78 x^3+20 x^2+4 x+22$
  • $y^2=81 x^6+4 x^5+29 x^4+56 x^3+60 x^2+12 x+66$
  • $y^2=14 x^6+62 x^5+58 x^4+16 x^3+59 x^2+86 x+19$
  • $y^2=42 x^6+8 x^5+85 x^4+48 x^3+88 x^2+80 x+57$
  • $y^2=84 x^6+45 x^5+54 x^4+72 x^3+16 x^2+49 x+46$
  • $y^2=38 x^6+11 x^5+63 x^4+52 x^3+52 x^2+73 x+57$
  • $y^2=25 x^6+33 x^5+11 x^4+67 x^3+67 x^2+41 x+82$
  • $y^2=52 x^6+77 x^5+25 x^4+16 x^3+36 x^2+58 x+37$
  • $y^2=67 x^6+53 x^5+75 x^4+48 x^3+19 x^2+85 x+22$
  • $y^2=20 x^6+60 x^5+17 x^4+21 x^3+65 x^2+81 x$
  • $y^2=60 x^6+2 x^5+51 x^4+63 x^3+17 x^2+65 x$
  • $y^2=42 x^6+75 x^5+18 x^4+51 x^3+58 x^2+56 x+53$
  • $y^2=37 x^6+47 x^5+54 x^4+64 x^3+85 x^2+79 x+70$
  • $y^2=38 x^6+13 x^5+84 x^4+75 x^3+42 x^2+79 x+14$
  • $y^2=25 x^6+39 x^5+74 x^4+47 x^3+37 x^2+59 x+42$
  • $y^2=52 x^6+33 x^5+18 x^4+76 x^3+34 x^2+54 x+50$
  • $y^2=67 x^6+10 x^5+54 x^4+50 x^3+13 x^2+73 x+61$
  • $y^2=72 x^6+61 x^5+86 x^4+79 x^3+9 x^2+6 x+4$
  • and 661 more

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{89^{2}}$.

Endomorphism algebra over $\F_{89}$
The endomorphism algebra of this simple isogeny class is \(\Q(i, \sqrt{53})\).
Endomorphism algebra over $\overline{\F}_{89}$
The base change of $A$ to $\F_{89^{2}}$ is 1.7921.abi 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-53}) \)$)$

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.89.ay_mk$4$(not in LMFDB)
2.89.a_bi$4$(not in LMFDB)
2.89.y_mk$4$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.89.ay_mk$4$(not in LMFDB)
2.89.a_bi$4$(not in LMFDB)
2.89.y_mk$4$(not in LMFDB)
2.89.am_cd$12$(not in LMFDB)
2.89.m_cd$12$(not in LMFDB)