Properties

Label 4.4.19025.1-20.1-a2
Base field 4.4.19025.1
Conductor norm \( 20 \)
CM no
Base change no
Q-curve no
Torsion order \( 2 \)
Rank \( 1 \)

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Base field 4.4.19025.1

Generator \(a\), with minimal polynomial \( x^{4} - 2 x^{3} - 13 x^{2} + 14 x + 44 \); class number \(1\).

Copy content comment:Define the base number field
 
Copy content sage:R.<x> = PolynomialRing(QQ); K.<a> = NumberField(R([44, 14, -13, -2, 1]))
 
Copy content gp:K = nfinit(Polrev([44, 14, -13, -2, 1]));
 
Copy content magma:R<x> := PolynomialRing(Rationals()); K<a> := NumberField(R![44, 14, -13, -2, 1]);
 
Copy content oscar:Qx, x = polynomial_ring(QQ); K, a = number_field(Qx([44, 14, -13, -2, 1]))
 

Weierstrass equation

\({y}^2+\left(\frac{1}{2}a^{3}-\frac{7}{2}a-4\right){x}{y}+\left(\frac{1}{2}a^{3}-\frac{9}{2}a-3\right){y}={x}^{3}+\left(\frac{1}{2}a^{3}-a^{2}-\frac{7}{2}a+5\right){x}^{2}+\left(\frac{145}{2}a^{3}-\frac{327}{2}a^{2}-390a+208\right){x}+\frac{1941}{2}a^{3}-2209a^{2}-\frac{10503}{2}a+2658\)
Copy content comment:Define the curve
 
Copy content sage:E = EllipticCurve([K([-4,-7/2,0,1/2]),K([5,-7/2,-1,1/2]),K([-3,-9/2,0,1/2]),K([208,-390,-327/2,145/2]),K([2658,-10503/2,-2209,1941/2])])
 
Copy content gp:E = ellinit([Polrev([-4,-7/2,0,1/2]),Polrev([5,-7/2,-1,1/2]),Polrev([-3,-9/2,0,1/2]),Polrev([208,-390,-327/2,145/2]),Polrev([2658,-10503/2,-2209,1941/2])], K);
 
Copy content magma:E := EllipticCurve([K![-4,-7/2,0,1/2],K![5,-7/2,-1,1/2],K![-3,-9/2,0,1/2],K![208,-390,-327/2,145/2],K![2658,-10503/2,-2209,1941/2]]);
 
Copy content oscar:E = elliptic_curve([K([-4,-7/2,0,1/2]),K([5,-7/2,-1,1/2]),K([-3,-9/2,0,1/2]),K([208,-390,-327/2,145/2]),K([2658,-10503/2,-2209,1941/2])])
 

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$$\hat{h}(P)$Order
$\left(-\frac{3639}{1210} a^{3} + \frac{3221}{605} a^{2} + \frac{21391}{1210} a + \frac{324}{121} : -\frac{623707}{66550} a^{3} + \frac{482267}{13310} a^{2} + \frac{757973}{33275} a - \frac{3521633}{33275} : 1\right)$$3.8495530509208297746029141114450957595$$\infty$
$\left(-a^{3} - \frac{17}{4} a^{2} + 17 a + 35 : -\frac{7}{8} a^{3} - \frac{27}{4} a^{2} + \frac{47}{2} a + 55 : 1\right)$$0$$2$

Invariants

Conductor: $\frak{N}$ = \((-a-1)\) = \((1/2a^3-7/2a-1)\cdot(-1/2a^3+3/2a^2+3a-9)\)
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: $N(\frak{N})$ = \( 20 \) = \(4\cdot5\)
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: $\Delta$ = $-13/2a^3+11a^2+93/2a-81$
Discriminant ideal: $\frak{D}_{\mathrm{min}} = (\Delta)$ = \((-13/2a^3+11a^2+93/2a-81)\) = \((1/2a^3-7/2a-1)^{6}\cdot(-1/2a^3+3/2a^2+3a-9)^{3}\)
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: $N(\frak{D}_{\mathrm{min}}) = N(\Delta)$ = \( -512000 \) = \(-4^{6}\cdot5^{3}\)
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: $j$ = \( -\frac{193066453992715621}{1600} a^{3} + \frac{442116976490500419}{800} a^{2} + \frac{11429398180028347}{80} a - \frac{51448046581033861}{25} \)
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: $\mathrm{Reg}(E/K)$ \( 3.8495530509208297746029141114450957595 \)
Néron-Tate Regulator: $\mathrm{Reg}_{\mathrm{NT}}(E/K)$ \( 15.398212203683319098411656445780383038 \)
Global period: $\Omega(E/K)$ \( 17.841628351168177837105113396511790217 \)
Tamagawa product: $\prod_{\frak{p}}c_{\frak{p}}$= \( 6 \)  =  \(( 2 \cdot 3 )\cdot1\)
Torsion order: $\#E(K)_{\mathrm{tor}}$= \(2\)
Special value: $L^{(r)}(E/K,1)/r!$ \( 2.98767749196749 \)
Analytic order of Ш: Ш${}_{\mathrm{an}}$= \( 1 \) (rounded)

BSD formula

$$\begin{aligned}2.987677492 \approx L'(E/K,1) & \overset{?}{=} \frac{ \# ะจ(E/K) \cdot \Omega(E/K) \cdot \mathrm{Reg}_{\mathrm{NT}}(E/K) \cdot \prod_{\mathfrak{p}} c_{\mathfrak{p}} } { \#E(K)_{\mathrm{tor}}^2 \cdot \left|d_K\right|^{1/2} } \\ & \approx \frac{ 1 \cdot 17.841628 \cdot 15.398212 \cdot 6 } { {2^2 \cdot 137.931142} } \\ & \approx 2.987677492 \end{aligned}$$

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 semistable. There are 2 primes $\frak{p}$ of bad reduction.

$\mathfrak{p}$ $N(\mathfrak{p})$ Tamagawa number Kodaira symbol Reduction type Root number \(\mathrm{ord}_{\mathfrak{p}}(\mathfrak{N}\)) \(\mathrm{ord}_{\mathfrak{p}}(\mathfrak{D}_{\mathrm{min}}\)) \(\mathrm{ord}_{\mathfrak{p}}(\mathrm{den}(j))\)
\((1/2a^3-7/2a-1)\) \(4\) \(6\) \(I_{6}\) Split multiplicative \(-1\) \(1\) \(6\) \(6\)
\((-1/2a^3+3/2a^2+3a-9)\) \(5\) \(1\) \(I_{3}\) Non-split multiplicative \(1\) \(1\) \(3\) \(3\)

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.1.2

Isogenies and isogeny class

This curve has non-trivial cyclic isogenies of degree \(d\) for \(d=\) 2, 3 and 6.
Its isogeny class 20.1-a consists of curves linked by isogenies of degrees dividing 6.

Base change

This elliptic curve is not a \(\Q\)-curve.

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