Properties

Label 2.29.a_c
Base field $\F_{29}$
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:  $\F_{29}$
Dimension:  $2$
L-polynomial:  $1 + 2 x^{2} + 841 x^{4}$
Frobenius angles:  $\pm0.255489189683$, $\pm0.744510810317$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(\sqrt{14}, \sqrt{-15})\)
Galois group:  $C_2^2$
Jacobians:  $52$
Isomorphism classes:  128
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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $844$ $712336$ $594818284$ $502624281600$ $420707240339404$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $30$ $846$ $24390$ $710638$ $20511150$ $594813246$ $17249876310$ $500243610718$ $14507145975870$ $420707247378606$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 52 curves (of which all are hyperelliptic):

  • $y^2=2 x^6+2 x^5+23 x^4+15 x^3+11 x^2+13 x+16$
  • $y^2=4 x^6+4 x^5+17 x^4+x^3+22 x^2+26 x+3$
  • $y^2=4 x^6+17 x^5+2 x^4+10 x^3+3 x^2+25 x+25$
  • $y^2=8 x^6+5 x^5+4 x^4+20 x^3+6 x^2+21 x+21$
  • $y^2=12 x^6+2 x^5+20 x^4+2 x^3+17 x^2+10 x+22$
  • $y^2=7 x^6+22 x^5+24 x^4+19 x^3+3 x^2+11 x+18$
  • $y^2=22 x^6+17 x^5+12 x^4+21 x^3+22 x^2+22 x+20$
  • $y^2=15 x^6+5 x^5+24 x^4+13 x^3+15 x^2+15 x+11$
  • $y^2=4 x^6+6 x^5+9 x^4+16 x^3+11 x^2+8 x+20$
  • $y^2=8 x^6+12 x^5+18 x^4+3 x^3+22 x^2+16 x+11$
  • $y^2=20 x^6+14 x^5+15 x^4+24 x^3+23 x^2+19 x+1$
  • $y^2=11 x^6+28 x^5+x^4+19 x^3+17 x^2+9 x+2$
  • $y^2=20 x^6+21 x^5+13 x^4+25 x^3+x^2+18 x+11$
  • $y^2=11 x^6+26 x^5+24 x^4+5 x^3+7 x^2+19 x+9$
  • $y^2=22 x^6+23 x^5+19 x^4+10 x^3+14 x^2+9 x+18$
  • $y^2=21 x^6+28 x^5+21 x^4+25 x^3+4 x^2+7 x+1$
  • $y^2=28 x^6+13 x^5+8 x^4+7 x^3+x^2+28 x+1$
  • $y^2=27 x^6+26 x^5+16 x^4+14 x^3+2 x^2+27 x+2$
  • $y^2=8 x^6+28 x^4+25 x^3+17 x^2+20$
  • $y^2=8 x^6+9 x^5+x^4+21 x^3+2 x^2+5 x+12$
  • and 32 more

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{29^{2}}$.

Endomorphism algebra over $\F_{29}$
The endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{14}, \sqrt{-15})\).
Endomorphism algebra over $\overline{\F}_{29}$
The base change of $A$ to $\F_{29^{2}}$ is 1.841.c 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-210}) \)$)$

Base change

This is a primitive isogeny class.

Twists

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

TwistExtension degreeCommon base change
2.29.a_ac$4$(not in LMFDB)