Properties

Label 2.2.40.1-72.1-d6
Base field \(\Q(\sqrt{10}) \)
Conductor norm \( 72 \)
CM no
Base change no
Q-curve no
Torsion order \( 2 \)
Rank \( 1 \)

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Base field \(\Q(\sqrt{10}) \)

Generator \(a\), with minimal polynomial \( x^{2} - 10 \); class number \(2\).

Copy content comment:Define the base number field
 
Copy content sage:R.<x> = PolynomialRing(QQ); K.<a> = NumberField(R([-10, 0, 1]))
 
Copy content gp:K = nfinit(Polrev([-10, 0, 1]));
 
Copy content magma:R<x> := PolynomialRing(Rationals()); K<a> := NumberField(R![-10, 0, 1]);
 

Weierstrass equation

\({y}^2={x}^{3}-a{x}^{2}+\left(-1052a-3421\right){x}-32553a-103446\)
Copy content comment:Define the curve
 
Copy content sage:E = EllipticCurve([K([0,0]),K([0,-1]),K([0,0]),K([-3421,-1052]),K([-103446,-32553])])
 
Copy content gp:E = ellinit([Polrev([0,0]),Polrev([0,-1]),Polrev([0,0]),Polrev([-3421,-1052]),Polrev([-103446,-32553])], K);
 
Copy content magma:E := EllipticCurve([K![0,0],K![0,-1],K![0,0],K![-3421,-1052],K![-103446,-32553]]);
 

This is not a global minimal model: it is minimal at all primes except \((2,a)\). No global minimal model exists.

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$$\hat{h}(P)$Order
$\left(-\frac{151}{9} a + \frac{121}{18} : -\frac{7999}{108} a + \frac{6305}{27} : 1\right)$$4.6622222270910408496966407535149275521$$\infty$
$\left(-9 a - 18 : 0 : 1\right)$$0$$2$

Invariants

Conductor: $\frak{N}$ = \((12,6a)\) = \((2,a)^{3}\cdot(3,a+1)\cdot(3,a+2)\)
Copy content comment:Compute the conductor
 
Copy content sage:E.conductor()
 
Copy content gp:ellglobalred(E)[1]
 
Copy content magma:Conductor(E);
 
Conductor norm: $N(\frak{N})$ = \( 72 \) = \(2^{3}\cdot3\cdot3\)
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));
 
Discriminant: $\Delta$ = $26118144a+72087552$
Discriminant ideal: $(\Delta)$ = \((26118144a+72087552)\) = \((2,a)^{22}\cdot(3,a+1)^{2}\cdot(3,a+2)^{16}\)
Copy content comment:Compute the discriminant
 
Copy content sage:E.discriminant()
 
Copy content gp:E.disc
 
Copy content magma:Discriminant(E);
 
Discriminant norm: $N(\Delta)$ = \( -1624959306694656 \) = \(-2^{22}\cdot3^{2}\cdot3^{16}\)
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));
 
Minimal discriminant: $\frak{D}_{\mathrm{min}}$ = \((-97920a+701856)\) = \((2,a)^{10}\cdot(3,a+1)^{2}\cdot(3,a+2)^{16}\)
Minimal discriminant norm: $N(\frak{D}_{\mathrm{min}})$ = \( -396718580736 \) = \(-2^{10}\cdot3^{2}\cdot3^{16}\)
j-invariant: $j$ = \( \frac{1497379111186634}{43046721} a + \frac{4734706974798626}{43046721} \)
Copy content comment:Compute the j-invariant
 
Copy content sage:E.j_invariant()
 
Copy content gp:E.j
 
Copy content magma:jInvariant(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: $\mathrm{Reg}(E/K)$ \( 4.6622222270910408496966407535149275521 \)
Néron-Tate Regulator: $\mathrm{Reg}_{\mathrm{NT}}(E/K)$ \( 9.3244444541820816993932815070298551042 \)
Global period: $\Omega(E/K)$ \( 0.79537295142944673415870937404860456976 \)
Tamagawa product: $\prod_{\frak{p}}c_{\frak{p}}$= \( 8 \)  =  \(2\cdot2\cdot2\)
Torsion order: $\#E(K)_{\mathrm{tor}}$= \(2\)
Special value: $L^{(r)}(E/K,1)/r!$ \( 2.3452750526555100112690638722856226608 \)
Analytic order of Ш: Ш${}_{\mathrm{an}}$= \( 1 \) (rounded)

BSD formula

$$\begin{aligned}2.345275053 \approx L'(E/K,1) & \overset{?}{=} \frac{ \# ะจ(E/K) \cdot \Omega(E/K) \cdot \mathrm{Reg}_{\mathrm{NT}}(E/K) \cdot \prod_{\mathfrak{p}} c_{\mathfrak{p}} } { \#E(K)_{\mathrm{tor}}^2 \cdot \left|d_K\right|^{1/2} } \\ & \approx \frac{ 1 \cdot 0.795373 \cdot 9.324444 \cdot 8 } { {2^2 \cdot 6.324555} } \\ & \approx 2.345275053 \end{aligned}$$

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 3 primes $\frak{p}$ of bad reduction. Primes of good reduction for the curve but which divide the discriminant of the model above (if any) are included.

$\mathfrak{p}$ $N(\mathfrak{p})$ Tamagawa number Kodaira symbol Reduction type Root number \(\mathrm{ord}_{\mathfrak{p}}(\mathfrak{N}\)) \(\mathrm{ord}_{\mathfrak{p}}(\mathfrak{D}_{\mathrm{min}}\)) \(\mathrm{ord}_{\mathfrak{p}}(\mathrm{den}(j))\)
\((2,a)\) \(2\) \(2\) \(III^{*}\) Additive \(1\) \(3\) \(10\) \(0\)
\((3,a+1)\) \(3\) \(2\) \(I_{2}\) Split multiplicative \(-1\) \(1\) \(2\) \(2\)
\((3,a+2)\) \(3\) \(2\) \(I_{16}\) Non-split multiplicative \(1\) \(1\) \(16\) \(16\)

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

Isogenies and isogeny class

This curve has non-trivial cyclic isogenies of degree \(d\) for \(d=\) 2, 4 and 8.
Its isogeny class 72.1-d consists of curves linked by isogenies of degrees dividing 8.

Base change

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

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