Properties

Label 122018f2
Conductor 122018122018
Discriminant 5.542×10195.542\times 10^{19}
j-invariant 469097433244036 \frac{469097433}{244036}
CM no
Rank 00
Torsion structure Z/2ZZ/2Z\Z/{2}\Z \oplus \Z/{2}\Z

Related objects

Downloads

Learn more

Show commands: Magma / Oscar / PariGP / SageMath

Minimal Weierstrass equation

Minimal Weierstrass equation

Simplified equation

y2+xy=x3x2987583x119835975y^2+xy=x^3-x^2-987583x-119835975 Copy content Toggle raw display (homogenize, simplify)
y2z+xyz=x3x2z987583xz2119835975z3y^2z+xyz=x^3-x^2z-987583xz^2-119835975z^3 Copy content Toggle raw display (dehomogenize, simplify)
y2=x315801331x7685303730y^2=x^3-15801331x-7685303730 Copy content Toggle raw display (homogenize, minimize)

comment: Define the curve
 
sage: E = EllipticCurve([1, -1, 0, -987583, -119835975])
 
gp: E = ellinit([1, -1, 0, -987583, -119835975])
 
magma: E := EllipticCurve([1, -1, 0, -987583, -119835975]);
 
oscar: E = elliptic_curve([1, -1, 0, -987583, -119835975])
 
sage: E.short_weierstrass_model()
 
magma: WeierstrassModel(E);
 
oscar: short_weierstrass_model(E)
 

Mordell-Weil group structure

Z/2ZZ/2Z\Z/{2}\Z \oplus \Z/{2}\Z

magma: MordellWeilGroup(E);
 

Mordell-Weil generators

PPh^(P)\hat{h}(P)Order
(926,463)(-926, 463)0022
(1050,525)(1050, -525)0022

Integral points

(926,463) \left(-926, 463\right) , (1050,525) \left(1050, -525\right) Copy content Toggle raw display

comment: Integral points
 
sage: E.integral_points()
 
magma: IntegralPoints(E);
 

Invariants

Conductor: NN  =  122018 122018  = 21321922 \cdot 13^{2} \cdot 19^{2}
comment: Conductor
 
sage: E.conductor().factor()
 
gp: ellglobalred(E)[1]
 
magma: Conductor(E);
 
oscar: conductor(E)
 
Discriminant: Δ\Delta  =  5541605649833553024455416056498335530244 = 221381982^{2} \cdot 13^{8} \cdot 19^{8}
comment: Discriminant
 
sage: E.discriminant().factor()
 
gp: E.disc
 
magma: Discriminant(E);
 
oscar: discriminant(E)
 
j-invariant: jj  =  469097433244036 \frac{469097433}{244036}  = 2233731321923732^{-2} \cdot 3^{3} \cdot 7^{3} \cdot 13^{-2} \cdot 19^{-2} \cdot 37^{3}
comment: j-invariant
 
sage: E.j_invariant().factor()
 
gp: E.j
 
magma: jInvariant(E);
 
oscar: j_invariant(E)
 
Endomorphism ring: End(E)\mathrm{End}(E) = Z\Z
Geometric endomorphism ring: End(EQ)\mathrm{End}(E_{\overline{\Q}})  =  Z\Z    (no potential complex multiplication)
sage: E.has_cm()
 
magma: HasComplexMultiplication(E);
 
Sato-Tate group: ST(E)\mathrm{ST}(E) = SU(2)\mathrm{SU}(2)
Faltings height: hFaltingsh_{\mathrm{Faltings}} ≈ 2.48035001101087257744233796332.4803500110108725774423379633
gp: ellheight(E)
 
magma: FaltingsHeight(E);
 
oscar: faltings_height(E)
 
Stable Faltings height: hstableh_{\mathrm{stable}} ≈ 0.27434415730311602058891947342-0.27434415730311602058891947342
magma: StableFaltingsHeight(E);
 
oscar: stable_faltings_height(E)
 
abcabc quality: QQ ≈ 0.96357687299835240.9635768729983524
Szpiro ratio: σm\sigma_{m} ≈ 4.5272366634791024.527236663479102

BSD invariants

Analytic rank: ranr_{\mathrm{an}} = 0 0
sage: E.analytic_rank()
 
gp: ellanalyticrank(E)
 
magma: AnalyticRank(E);
 
Mordell-Weil rank: rr = 0 0
comment: Rank
 
sage: E.rank()
 
gp: [lower,upper] = ellrank(E)
 
magma: Rank(E);
 
Regulator: Reg(E/Q)\mathrm{Reg}(E/\Q) = 11
comment: Regulator
 
sage: E.regulator()
 
G = E.gen \\ if available
 
matdet(ellheightmatrix(E,G))
 
magma: Regulator(E);
 
Real period: Ω\Omega ≈ 0.160341035590794406583658828270.16034103559079440658365882827
comment: Real Period
 
sage: E.period_lattice().omega()
 
gp: if(E.disc>0,2,1)*E.omega[1]
 
magma: (Discriminant(E) gt 0 select 2 else 1) * RealPeriod(E);
 
Tamagawa product: pcp\prod_{p}c_p = 32 32  = 22222 2\cdot2^{2}\cdot2^{2}
comment: Tamagawa numbers
 
sage: E.tamagawa_numbers()
 
gp: gr=ellglobalred(E); [[gr[4][i,1],gr[5][i][4]] | i<-[1..#gr[4][,1]]]
 
magma: TamagawaNumbers(E);
 
oscar: tamagawa_numbers(E)
 
Torsion order: #E(Q)tor\#E(\Q)_{\mathrm{tor}} = 44
comment: Torsion order
 
sage: E.torsion_order()
 
gp: elltors(E)[1]
 
magma: Order(TorsionSubgroup(E));
 
oscar: prod(torsion_structure(E)[1])
 
Special value: L(E,1) L(E,1) ≈ 0.320682071181588813167317656530.32068207118158881316731765653
comment: Special L-value
 
r = E.rank();
 
E.lseries().dokchitser().derivative(1,r)/r.factorial()
 
gp: [r,L1r] = ellanalyticrank(E); L1r/r!
 
magma: Lr1 where r,Lr1 := AnalyticRank(E: Precision:=12);
 
Analytic order of Ш: Шan{}_{\mathrm{an}}  =  11    (exact)
comment: Order of Sha
 
sage: E.sha().an_numerical()
 
magma: MordellWeilShaInformation(E);
 

BSD formula

0.320682071L(E,1)=#Ш(E/Q)ΩEReg(E/Q)pcp#E(Q)tor210.1603411.00000032420.320682071\displaystyle 0.320682071 \approx L(E,1) = \frac{\# Ш(E/\Q)\cdot \Omega_E \cdot \mathrm{Reg}(E/\Q) \cdot \prod_p c_p}{\#E(\Q)_{\rm tor}^2} \approx \frac{1 \cdot 0.160341 \cdot 1.000000 \cdot 32}{4^2} \approx 0.320682071

# self-contained SageMath code snippet for the BSD formula (checks rank, computes analytic sha)
 
E = EllipticCurve(%s); r = E.rank(); ar = E.analytic_rank(); assert r == ar;
 
Lr1 = E.lseries().dokchitser().derivative(1,r)/r.factorial(); sha = E.sha().an_numerical();
 
omega = E.period_lattice().omega(); reg = E.regulator(); tam = E.tamagawa_product(); tor = E.torsion_order();
 
assert r == ar; print("analytic sha: " + str(RR(Lr1) * tor^2 / (omega * reg * tam)))
 
/* self-contained Magma code snippet for the BSD formula (checks rank, computes analytic sha) */
 
E := EllipticCurve(%s); r := Rank(E); ar,Lr1 := AnalyticRank(E: Precision := 12); assert r eq ar;
 
sha := MordellWeilShaInformation(E); omega := RealPeriod(E) * (Discriminant(E) gt 0 select 2 else 1);
 
reg := Regulator(E); tam := &*TamagawaNumbers(E); tor := #TorsionSubgroup(E);
 
assert r eq ar; print "analytic sha:", Lr1 * tor^2 / (omega * reg * tam);
 

Modular invariants

Modular form 122018.2.a.j

qq2+q42q54q7q83q9+2q104q11+4q14+q16+2q17+3q18+O(q20) q - q^{2} + q^{4} - 2 q^{5} - 4 q^{7} - q^{8} - 3 q^{9} + 2 q^{10} - 4 q^{11} + 4 q^{14} + q^{16} + 2 q^{17} + 3 q^{18} + O(q^{20}) Copy content Toggle raw display

comment: q-expansion of modular form
 
sage: E.q_eigenform(20)
 
\\ actual modular form, use for small N
 
[mf,F] = mffromell(E)
 
Ser(mfcoefs(mf,20),q)
 
\\ or just the series
 
Ser(ellan(E,20),q)*q
 
magma: ModularForm(E);
 

For more coefficients, see the Downloads section to the right.

Modular degree: 4112640
comment: Modular degree
 
sage: E.modular_degree()
 
gp: ellmoddegree(E)
 
magma: ModularDegree(E);
 
Γ0(N) \Gamma_0(N) -optimal: no
Manin constant: 1
comment: Manin constant
 
magma: ManinConstant(E);
 

Local data at primes of bad reduction

This elliptic curve is not semistable. There are 3 primes pp of bad reduction:

pp Tamagawa number Kodaira symbol Reduction type Root number ordp(N)\mathrm{ord}_p(N) ordp(Δ)\mathrm{ord}_p(\Delta) ordp(den(j))\mathrm{ord}_p(\mathrm{den}(j))
22 22 I2I_{2} nonsplit multiplicative 1 1 2 2
1313 44 I2I_{2}^{*} additive 1 2 8 2
1919 44 I2I_{2}^{*} additive -1 2 8 2

comment: Local data
 
sage: E.local_data()
 
gp: ellglobalred(E)[5]
 
magma: [LocalInformation(E,p) : p in BadPrimes(E)];
 
oscar: [(p,tamagawa_number(E,p), kodaira_symbol(E,p), reduction_type(E,p)) for p in bad_primes(E)]
 

Galois representations

The \ell-adic Galois representation has maximal image for all primes \ell except those listed in the table below.

prime \ell mod-\ell image \ell-adic image
22 2Cs 8.12.0.2

comment: mod p Galois image
 
sage: rho = E.galois_representation(); [rho.image_type(p) for p in rho.non_surjective()]
 
magma: [GaloisRepresentation(E,p): p in PrimesUpTo(20)];
 

gens = [[1, 0, 4, 1], [1519, 1974, 0, 1975], [621, 1974, 1562, 1], [1, 4, 0, 1], [1973, 4, 1972, 5], [989, 4, 2, 9], [1485, 4, 990, 3]]
 
GL(2,Integers(1976)).subgroup(gens)
 
Gens := [[1, 0, 4, 1], [1519, 1974, 0, 1975], [621, 1974, 1562, 1], [1, 4, 0, 1], [1973, 4, 1972, 5], [989, 4, 2, 9], [1485, 4, 990, 3]];
 
sub<GL(2,Integers(1976))|Gens>;
 

The image H:=ρE(Gal(Q/Q))H:=\rho_E(\Gal(\overline{\Q}/\Q)) of the adelic Galois representation has level 1976=231319 1976 = 2^{3} \cdot 13 \cdot 19 , index 4848, genus 00, and generators

(1041),(1519197401975),(621197415621),(1401),(1973419725),(989429),(148549903)\left(\begin{array}{rr} 1 & 0 \\ 4 & 1 \end{array}\right),\left(\begin{array}{rr} 1519 & 1974 \\ 0 & 1975 \end{array}\right),\left(\begin{array}{rr} 621 & 1974 \\ 1562 & 1 \end{array}\right),\left(\begin{array}{rr} 1 & 4 \\ 0 & 1 \end{array}\right),\left(\begin{array}{rr} 1973 & 4 \\ 1972 & 5 \end{array}\right),\left(\begin{array}{rr} 989 & 4 \\ 2 & 9 \end{array}\right),\left(\begin{array}{rr} 1485 & 4 \\ 990 & 3 \end{array}\right).

Input positive integer mm to see the generators of the reduction of HH to GL2(Z/mZ)\mathrm{GL}_2(\Z/m\Z):

The torsion field K:=Q(E[1976])K:=\Q(E[1976]) is a degree-103255326720103255326720 Galois extension of Q\Q with Gal(K/Q)\Gal(K/\Q) isomorphic to the projection of HH to GL2(Z/1976Z)\GL_2(\Z/1976\Z).

The table below list all primes \ell for which the Serre invariants associated to the mod-\ell Galois representation are exceptional.

\ell Reduction type Serre weight Serre conductor
22 nonsplit multiplicative 44 61009=132192 61009 = 13^{2} \cdot 19^{2}
1313 additive 9898 722=2192 722 = 2 \cdot 19^{2}
1919 additive 200200 338=2132 338 = 2 \cdot 13^{2}

Isogenies

gp: ellisomat(E)
 

This curve has non-trivial cyclic isogenies of degree dd for d=d= 2.
Its isogeny class 122018f consists of 4 curves linked by isogenies of degrees dividing 4.

Twists

The minimal quadratic twist of this elliptic curve is 494b2, its twist by 247-247.

Growth of torsion in number fields

The number fields KK of degree less than 24 such that E(K)torsE(K)_{\rm tors} is strictly larger than E(Q)torsE(\Q)_{\rm tors} Z/2ZZ/2Z\cong \Z/{2}\Z \oplus \Z/{2}\Z are as follows:

[K:Q][K:\Q] KK E(K)torsE(K)_{\rm tors} Base change curve
44 Q(13,19)\Q(\sqrt{-13}, \sqrt{19}) Z/2ZZ/4Z\Z/2\Z \oplus \Z/4\Z not in database
44 Q(19,26)\Q(\sqrt{-19}, \sqrt{26}) Z/2ZZ/4Z\Z/2\Z \oplus \Z/4\Z not in database
44 Q(13,38)\Q(\sqrt{13}, \sqrt{38}) Z/2ZZ/4Z\Z/2\Z \oplus \Z/4\Z not in database
88 deg 8 Z/2ZZ/6Z\Z/2\Z \oplus \Z/6\Z not in database
1616 16.0.59502537583409845208199725056.1 Z/4ZZ/4Z\Z/4\Z \oplus \Z/4\Z not in database
1616 deg 16 Z/2ZZ/8Z\Z/2\Z \oplus \Z/8\Z not in database
1616 deg 16 Z/2ZZ/8Z\Z/2\Z \oplus \Z/8\Z not in database
1616 deg 16 Z/2ZZ/8Z\Z/2\Z \oplus \Z/8\Z not in database

We only show fields where the torsion growth is primitive. For fields not in the database, click on the degree shown to reveal the defining polynomial.

Iwasawa invariants

pp 2 13 19
Reduction type nonsplit add add
λ\lambda-invariant(s) 2 - -
μ\mu-invariant(s) 0 - -

All Iwasawa λ\lambda and μ\mu-invariants for primes p3p\ge 3 of good reduction are zero.

An entry - indicates that the invariants are not computed because the reduction is additive.

pp-adic regulators

All pp-adic regulators are identically 11 since the rank is 00.