Properties

Label 2.0.4.1-40000.3-CMc1
Base field \(\Q(\sqrt{-1}) \)
Conductor norm \( 40000 \)
CM yes (\(-4\))
Base change yes
Q-curve yes
Torsion order \( 4 \)
Rank \( 2 \)

Related objects

Downloads

Learn more

Show commands: Magma / PariGP / SageMath

Base field \(\Q(\sqrt{-1}) \)

Generator \(i\), with minimal polynomial \( x^{2} + 1 \); class number \(1\).

sage: R.<x> = PolynomialRing(QQ); K.<a> = NumberField(R([1, 0, 1]))
 
gp: K = nfinit(Polrev([1, 0, 1]));
 
magma: R<x> := PolynomialRing(Rationals()); K<a> := NumberField(R![1, 0, 1]);
 

Weierstrass equation

\({y}^2={x}^{3}-25{x}\)
sage: E = EllipticCurve([K([0,0]),K([0,0]),K([0,0]),K([-25,0]),K([0,0])])
 
gp: E = ellinit([Polrev([0,0]),Polrev([0,0]),Polrev([0,0]),Polrev([-25,0]),Polrev([0,0])], K);
 
magma: E := EllipticCurve([K![0,0],K![0,0],K![0,0],K![-25,0],K![0,0]]);
 

This is a global minimal model.

sage: E.is_global_minimal_model()
 

Invariants

Conductor: \((200)\) = \((i+1)^{6}\cdot(-i-2)^{2}\cdot(2i+1)^{2}\)
sage: E.conductor()
 
gp: ellglobalred(E)[1]
 
magma: Conductor(E);
 
Conductor norm: \( 40000 \) = \(2^{6}\cdot5^{2}\cdot5^{2}\)
sage: E.conductor().norm()
 
gp: idealnorm(ellglobalred(E)[1])
 
magma: Norm(Conductor(E));
 
Discriminant: \((1000000)\) = \((i+1)^{12}\cdot(-i-2)^{6}\cdot(2i+1)^{6}\)
sage: E.discriminant()
 
gp: E.disc
 
magma: Discriminant(E);
 
Discriminant norm: \( 1000000000000 \) = \(2^{12}\cdot5^{6}\cdot5^{6}\)
sage: E.discriminant().norm()
 
gp: norm(E.disc)
 
magma: Norm(Discriminant(E));
 
j-invariant: \( 1728 \)
sage: E.j_invariant()
 
gp: E.j
 
magma: jInvariant(E);
 
Endomorphism ring: \(\Z[\sqrt{-1}]\) (complex multiplication)
Geometric endomorphism ring: \(\Z[\sqrt{-1}]\)
sage: E.has_cm(), E.cm_discriminant()
 
magma: HasComplexMultiplication(E);
 
Sato-Tate group: $\mathrm{U}(1)$

Mordell-Weil group

Rank: \(2\)
Generators $\left(-5 i + 10 : -25 i + 25 : 1\right)$ $\left(-4 i + 3 : -14 i - 2 : 1\right)$
Heights \(0.47487054313294889752680137739864947992\) \(0.94974108626589779505360275479729895983\)
Torsion structure: \(\Z/2\Z\oplus\Z/2\Z\)
sage: T = E.torsion_subgroup(); T.invariants()
 
gp: T = elltors(E); T[2]
 
magma: T,piT := TorsionSubgroup(E); Invariants(T);
 
Torsion generators: $\left(-5 : 0 : 1\right)$ $\left(0 : 0 : 1\right)$
sage: T.gens()
 
gp: T[3]
 
magma: [piT(P) : P in Generators(T)];
 

BSD invariants

Analytic rank: \( 2 \)
sage: E.rank()
 
magma: Rank(E);
 
Mordell-Weil rank: \(2\)
Regulator: \( 0.22550203273538187933728246363048114540 \)
Period: \( 1.3750371636040745654980191559621114396 \)
Tamagawa product: \( 64 \)  =  \(2^{2}\cdot2^{2}\cdot2^{2}\)
Torsion order: \(4\)
Leading coefficient: \( 4.9611788076706027444654575968043867917 \)
Analytic order of Ш: \( 1 \) (rounded)

Local data at primes of bad reduction

sage: E.local_data()
 
magma: LocalInformation(E);
 
prime Norm Tamagawa number Kodaira symbol Reduction type Root number ord(\(\mathfrak{N}\)) ord(\(\mathfrak{D}\)) ord\((j)_{-}\)
\((i+1)\) \(2\) \(4\) \(I_{2}^{*}\) Additive \(-1\) \(6\) \(12\) \(0\)
\((-i-2)\) \(5\) \(4\) \(I_0^{*}\) Additive \(1\) \(2\) \(6\) \(0\)
\((2i+1)\) \(5\) \(4\) \(I_0^{*}\) Additive \(1\) \(2\) \(6\) \(0\)

Galois Representations

The mod \( p \) Galois Representation has maximal image for all primes \( p < 1000 \) except those listed.

prime Image of Galois Representation
\(2\) 2Cs

For all other primes \(p\), the image is a split Cartan subgroup if \(\left(\frac{ -1 }{p}\right)=+1\) or a nonsplit Cartan subgroup if \(\left(\frac{ -1 }{p}\right)=-1\).

Isogenies and isogeny class

This curve has non-trivial cyclic isogenies (excluding endomorphisms) of degree \(d\) for \(d=\) 2.
Its isogeny class 40000.3-CMc consists of curves linked by isogenies of degree 2.

Base change

This elliptic curve is a \(\Q\)-curve. It is the base change of the following 2 elliptic curves:

Base field Curve
\(\Q\) 800.d4
\(\Q\) 800.d3