Properties

Label 2.0.8.1-41616.5-e3
Base field \(\Q(\sqrt{-2}) \)
Conductor norm \( 41616 \)
CM no
Base change no
Q-curve yes
Torsion order \( 2 \)
Rank \( 1 \)

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Base field \(\Q(\sqrt{-2}) \)

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

Copy content comment:Define the base number field
 
Copy content sage:R.<x> = PolynomialRing(QQ); K.<a> = NumberField(R([2, 0, 1]))
 
Copy content gp:K = nfinit(Polrev([2, 0, 1]));
 
Copy content magma:R<x> := PolynomialRing(Rationals()); K<a> := NumberField(R![2, 0, 1]);
 
Copy content oscar:Qx, x = polynomial_ring(QQ); K, a = number_field(Qx([2, 0, 1]))
 

Weierstrass equation

\({y}^2+a{x}{y}={x}^{3}+{x}^{2}+\left(-4360a+418\right){x}-97280a+146930\)
Copy content comment:Define the curve
 
Copy content sage:E = EllipticCurve([K([0,1]),K([1,0]),K([0,0]),K([418,-4360]),K([146930,-97280])])
 
Copy content gp:E = ellinit([Polrev([0,1]),Polrev([1,0]),Polrev([0,0]),Polrev([418,-4360]),Polrev([146930,-97280])], K);
 
Copy content magma:E := EllipticCurve([K![0,1],K![1,0],K![0,0],K![418,-4360],K![146930,-97280]]);
 
Copy content oscar:E = elliptic_curve([K([0,1]),K([1,0]),K([0,0]),K([418,-4360]),K([146930,-97280])])
 

This is a global minimal model.

Copy content comment:Test whether it is a global minimal model
 
Copy content sage:E.is_global_minimal_model()
 

Mordell-Weil group structure

\(\Z \oplus \Z/{2}\Z\)

Mordell-Weil generators

$P$$\hat{h}(P)$Order
$\left(-\frac{8176}{361} a - \frac{16127}{722} : -\frac{2080851}{27436} a + \frac{1227905}{13718} : 1\right)$$6.2931539160546365928133690826298624376$$\infty$
$\left(-16 a - \frac{73}{2} : \frac{73}{4} a - 16 : 1\right)$$0$$2$

Invariants

Conductor: $\frak{N}$ = \((204)\) = \((a)^{4}\cdot(-a-1)\cdot(a-1)\cdot(-2a+3)\cdot(2a+3)\)
Copy content comment:Compute the conductor
 
Copy content sage:E.conductor()
 
Copy content gp:ellglobalred(E)[1]
 
Copy content magma:Conductor(E);
 
Copy content oscar:conductor(E)
 
Conductor norm: $N(\frak{N})$ = \( 41616 \) = \(2^{4}\cdot3\cdot3\cdot17\cdot17\)
Copy content comment:Compute the norm of the conductor
 
Copy content sage:E.conductor().norm()
 
Copy content gp:idealnorm(K, ellglobalred(E)[1])
 
Copy content magma:Norm(Conductor(E));
 
Copy content oscar:norm(conductor(E))
 
Discriminant: $\Delta$ = $1788724321920a+1783310266368$
Discriminant ideal: $\frak{D}_{\mathrm{min}} = (\Delta)$ = \((1788724321920a+1783310266368)\) = \((a)^{15}\cdot(-a-1)^{6}\cdot(a-1)^{24}\cdot(-2a+3)^{4}\cdot(2a+3)\)
Copy content comment:Compute the discriminant
 
Copy content sage:E.discriminant()
 
Copy content gp:E.disc
 
Copy content magma:Discriminant(E);
 
Copy content oscar:discriminant(E)
 
Discriminant norm: $N(\frak{D}_{\mathrm{min}}) = N(\Delta)$ = \( 9579264905789834696884224 \) = \(2^{15}\cdot3^{6}\cdot3^{24}\cdot17^{4}\cdot17\)
Copy content comment:Compute the norm of the discriminant
 
Copy content sage:E.discriminant().norm()
 
Copy content gp:norm(E.disc)
 
Copy content magma:Norm(Discriminant(E));
 
Copy content oscar:norm(discriminant(E))
 
j-invariant: $j$ = \( -\frac{410311536960329978125}{94355189265718404} a - \frac{136155893118005119000}{23588797316429601} \)
Copy content comment:Compute the j-invariant
 
Copy content sage:E.j_invariant()
 
Copy content gp:E.j
 
Copy content magma:jInvariant(E);
 
Copy content oscar:j_invariant(E)
 
Endomorphism ring: $\mathrm{End}(E)$ = \(\Z\)   
Geometric endomorphism ring: $\mathrm{End}(E_{\overline{\Q}})$ = \(\Z\)    (no potential complex multiplication)
Copy content comment:Test for Complex Multiplication
 
Copy content sage:E.has_cm(), E.cm_discriminant()
 
Copy content magma:HasComplexMultiplication(E);
 
Sato-Tate group: $\mathrm{ST}(E)$ = $\mathrm{SU}(2)$

BSD invariants

Analytic rank: $r_{\mathrm{an}}$= \( 1 \)
Copy content comment:Compute the Mordell-Weil rank
 
Copy content sage:E.rank()
 
Copy content magma:Rank(E);
 
Mordell-Weil rank: $r$ = \(1\)
Regulator: $\mathrm{Reg}(E/K)$ \( 6.2931539160546365928133690826298624376 \)
Néron-Tate Regulator: $\mathrm{Reg}_{\mathrm{NT}}(E/K)$ \( 12.586307832109273185626738165259724875 \)
Global period: $\Omega(E/K)$ \( 0.207933967460669588201616490057428731420 \)
Tamagawa product: $\prod_{\frak{p}}c_{\frak{p}}$= \( 16 \)  =  \(2\cdot2\cdot2\cdot2\cdot1\)
Torsion order: $\#E(K)_{\mathrm{tor}}$= \(2\)
Special value: $L^{(r)}(E/K,1)/r!$ \( 3.7011679039764952941272628899277629300 \)
Analytic order of Ш: Ш${}_{\mathrm{an}}$= \( 1 \) (rounded)

BSD formula

$$\begin{aligned}3.701167904 \approx L'(E/K,1) & \overset{?}{=} \frac{ \# ะจ(E/K) \cdot \Omega(E/K) \cdot \mathrm{Reg}_{\mathrm{NT}}(E/K) \cdot \prod_{\mathfrak{p}} c_{\mathfrak{p}} } { \#E(K)_{\mathrm{tor}}^2 \cdot \left|d_K\right|^{1/2} } \\ & \approx \frac{ 1 \cdot 0.207934 \cdot 12.586308 \cdot 16 } { {2^2 \cdot 2.828427} } \\ & \approx 3.701167904 \end{aligned}$$

Local data at primes of bad reduction

Copy content comment:Compute the local reduction data at primes of bad reduction
 
Copy content sage:E.local_data()
 
Copy content magma:LocalInformation(E);
 

This elliptic curve is not semistable. There are 5 primes $\frak{p}$ of bad reduction.

$\mathfrak{p}$ $N(\mathfrak{p})$ Tamagawa number Kodaira symbol Reduction type Root number \(\mathrm{ord}_{\mathfrak{p}}(\mathfrak{N}\)) \(\mathrm{ord}_{\mathfrak{p}}(\mathfrak{D}_{\mathrm{min}}\)) \(\mathrm{ord}_{\mathfrak{p}}(\mathrm{den}(j))\)
\((a)\) \(2\) \(2\) \(I_{7}^{*}\) Additive \(1\) \(4\) \(15\) \(3\)
\((-a-1)\) \(3\) \(2\) \(I_{6}\) Non-split multiplicative \(1\) \(1\) \(6\) \(6\)
\((a-1)\) \(3\) \(2\) \(I_{24}\) Non-split multiplicative \(1\) \(1\) \(24\) \(24\)
\((-2a+3)\) \(17\) \(2\) \(I_{4}\) Non-split multiplicative \(1\) \(1\) \(4\) \(4\)
\((2a+3)\) \(17\) \(1\) \(I_{1}\) Non-split multiplicative \(1\) \(1\) \(1\) \(1\)

Galois Representations

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

prime Image of Galois Representation
\(2\) 2B
\(3\) 3B

Isogenies and isogeny class

This curve has non-trivial cyclic isogenies of degree \(d\) for \(d=\) 2, 3, 4, 6 and 12.
Its isogeny class 41616.5-e consists of curves linked by isogenies of degrees dividing 12.

Base change

This elliptic curve is a \(\Q\)-curve.

It is not the base change of an elliptic curve defined over any subfield.