All Questions
1,978 questions
-5
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On Mordell equation $y^2=x^3+k$ [closed]
Have the Mordell equation $y^2=x^3+k$ solved for all integer $k$ or not?
Please Could you tell me about a good review papers about such equation.
1
vote
1
answer
93
views
A correspondence between pairs of isogenies and representation numbers
This question is re-posted from MSE because it didn't seem to get any traction/responses there.
This is a question from this paper about a correspondence between representation numbers of quadratic ...
2
votes
1
answer
151
views
Flexes and projective equivalence of smooth cubics
I am trying to study Kock and Vainsencher's book "An invitation to Quantum Cohomology", working my way through the exercises. One of them ($0$th chapter) asks two prove that two elliptic ...
3
votes
0
answers
88
views
cubic twists of Mordell curve and their rank
Let $a$ be a non-zero integer. Consider the elliptic curve $E_a/\mathbb{Q}$ given by the equation
$$
E_a: y^2 = x^3 + a.
$$
For a cube-free integer $D$, define the elliptic curves $E_{aD^2}/\mathbb{Q}$...
6
votes
3
answers
4k
views
Re: Mordell's equation $y^2 = x^3 + k$ and perfect numbers
I have already tried a somewhat exhaustive search of the literature, but couldn't find anything close to the problem that I am working on.
My question is: When does Mordell's equation
$$Y^2 = X^3 + K$$...
2
votes
1
answer
383
views
Simple isogeny question
I'm looking for a reference of an isogeny fact that I've used many times but am having a hard time proving formally.
One can define the degree of an isogeny as the degree of extension fields of the ...
18
votes
2
answers
888
views
Serre’s comment on Hurwitz: connecting FLT to points of finite order on elliptic curves
In the paper Sur les représentations modulaire de degré 2 de Gal$(\overline{\mathbb{Q}}/\mathbb{Q})$, Serre makes the following comment:
Remarque. La relation existant entre "solutions de l'...
5
votes
1
answer
340
views
Equations for dual cubic curves
Suppose I have a cubic curve $C$ (over $\mathbb C$) in Weierstrass form $$y^2=x^3+ax+b.$$
I would like to find the degree $6$ equation for protectively dual curve $C^*$. Do you know any place where ...
0
votes
0
answers
66
views
Parametrization of elliptic curve with differential equation $(x,y)=(f(x),f'(x))$ involving Lambert $W$ function
For non-zero complex $A$, define the curve over the complex numbers
$C: x^2 y^2-A x-y=0$. $C$ is an elliptic curve.
$C$ has the differential equation parametrization $(x,y)=(f(x),f'(x))$
where
$$ f(x)=...
5
votes
0
answers
126
views
Using Lang–Trotter to get bounds on averages of Fourier coefficients
Let $E$ be an elliptic curve over $\mathbf{Q}$ and let $(a_n)$ be the sequence of Fourier coefficients for the weight two newform attached to $E$. The coefficients $a_p$ are the Frobenius traces given ...
10
votes
2
answers
286
views
Finding a model for $X_G$ with $G\subseteq \mathrm{GL}_2(\mathbb{Z}/N\mathbb{Z})$
I'm studying modular curves as part of my doctorate work and would like to understand how one gets from a subgroup $G$ of $\operatorname{GL}_2(\mathbb{Z}/N\mathbb{Z})$ to an equation for $X_G$. By $...
2
votes
1
answer
344
views
On Iwasawa theory of elliptic curves in $\mathrm{PGL}_2(\mathbb{Z}_p)$-extension
Let $E$ be an elliptic curve over the rationals $\mathbb{Q}$. We consider the Galois representation attached to $E$ by acting on its $p$-adic Tate module $T_p(E)$,
$$
\rho_E: G_{K} \rightarrow \mathrm{...
3
votes
1
answer
366
views
Descent for étale covers of proper regular models of elliptic curves
Let $K$ be a complete (but think Henselian suffice for purposes of this question) local field of characteristic $0$ with residue field $k$ of characteristic $p>0$ and ring of integers $R=\mathcal{O}...
4
votes
0
answers
100
views
Structure of points of elliptic curves in field with restricted ramification
Let $k$ be a finite field of characteristic $p$ and let $C$ be a curve over $k$. Let $E$ be a non-constant elliptic curve over $k(C)$. Taking the Néron model of $E$ and removing the singular fibers ...
3
votes
0
answers
139
views
Do the denominators of A006571(n)/A366450(n) have a Dirichlet generating function? Because they partially match A071974(n) and A056622(n)?
Consider the expansion: $$A006571(n) = q \prod _{k=1}^{\infty } \left(1-q^k\right)^2 \left(1-q^{11 k}\right)^2 \label{1}\tag{1}$$
A006571
and the triple sum:
$$A366450(n)=\sum _{k=1}^n \left(\sum _{y=...
7
votes
1
answer
233
views
Proven results for the refined Birch Swinnerton-Dyer conjecture over rationals when rank at most $1$
For an elliptic curve, $E$, defined over $\mathbb{Q}$ and with the Mordell-Weil group, $E(\mathbb{Q})$, having rank, $r$, the Birch Swinnerton-Dyer (BSD) conjecture states that
$$
c_{E} = \lim_{s \...
2
votes
1
answer
204
views
What does the Serre functor of equivariant category of fractional CY category look like?
I am considering the following set up. Let $\mathcal{A}$ be a fractional Calabi-Yau category and denote by $S$ the Serre functor and $S^m=[n]$. Now I consider a finite group action $G$ on $\mathcal{A}$...
3
votes
3
answers
1k
views
Rank and generators of elliptic curve
I need to calculate the rank and the generators of the elliptic curve
[0,1,0,-15662264585,746984342506759]
that is,
$$
y^2 = x^3 + x^2 -15662264585 x ...
5
votes
0
answers
172
views
"Genus theory" for elliptic curve $L$-functions
Let $d$ be a positive integer, so that $-d$ is a fundamental discriminant. This means that $d$ is square-free at odd primes and $\nu_2(d) \in \{0, 2, 3\}$. Further, if $\nu_2(d) > 0$ then $-d 2^{-\...
1
vote
0
answers
85
views
Action of Atkin--Lehner involution on CM points
In their first paper on Heegner points and derivatives of $L$-series, Gross and Zagier describe the action of Atkin--Lehner involutions on certain CM $\mathbf{C}$-points of the modular curve $X_0(N)$. ...
2
votes
0
answers
96
views
On the root numbers of quadruples of quadratic twists of elliptic curves
We got strong numerical evidence for the root numbers and analytic ranks
of quadruples of elliptic curves over the rationals.
Related to this question.
Let $k,k_1,k_2$ be squarefree pairwise coprime ...
0
votes
0
answers
108
views
looking for reference for two elliptic curves with equal formal group
I am looking for a reference.
In this post, @Chris Wurthrich made the following comment:
If the formal group laws (probably upon particular choice of coordinates) of two elliptic curves over any ring ...
3
votes
0
answers
241
views
Generating algebraic points on elliptic curves
Let $E$ be an elliptic curve over $\mathbf{Q}$. One has the modular parameterisation
\begin{align*}
\mathbf{H} \to X_0(N)(\mathbf{C}) \to E(\mathbf{C})
\end{align*}
where $X_0(N)$ is the modular curve ...
2
votes
1
answer
195
views
Can we get a homomorphism between two elliptic curves if we know a homomorphism between the respective formal groups?
Let $E_1$ and $E_2$ be two elliptic curves over a field of characteristic $0$, and let $\hat{E_1}$ and $\hat{E_2}$ be two formal group laws associated with $E_1$ and $E_2$, respectively. It is known ...
7
votes
3
answers
349
views
The rank of elliptic curves and related quadratic twists
Let $E/\mathbb{Q}$ be an elliptic curve, and let $k_1, k_2$ be square-free integers. Can anything be said about the related elliptic curves
$$\displaystyle E/\mathbb{Q}, E^{(k_1)}/\mathbb{Q}, E^{(k_2)}...
9
votes
3
answers
584
views
Do rational points on $X(1)$ correspond to elliptic curves up to rational isomorphism?
I'm not sure whether this is obvious or not. The curve $X(1)$ parametrices all elliptic curves up to isomorphism class over $\mathbb{
C}$, and a $K$-rational point corresponds to an elliptic curve ...
18
votes
2
answers
2k
views
What is the taxicab number for rational fourth powers?
The taxicab number is the smallest integer that can be expressed as a sum of two positive integer cubes in two different ways, and it is equal to $1729=12^3+1^3=10^3+9^3$. There are generalizations to ...
3
votes
1
answer
103
views
special $g_3^1$ on elliptic curve
Let $C$ be a planar smooth cubic curve. We know that projection from a point $p$ that does not lie on $C$ produces a 3-to-1 map $\pi: C\to \mathbb P^1$, which has 6 ramification points in general.
Now,...
7
votes
0
answers
170
views
Nondeterminism in Magma software while computing generators of an elliptic curve
Computing generators of a Mordell curve
$$y^2 = x^3 - 44275089430000,$$
can be done in Magma by running the following code:
...
1
vote
1
answer
143
views
Algorithm for computing isogeny class of elliptic curve
Is there an algorithm for computing the entire isogeny class of a given elliptic curve $E/\mathbb{Q}$?
References/ideas are welcome. Thanks!
17
votes
2
answers
2k
views
How to think of algebraic geometry in characteristic p?
How does a working mathematician usually think about algebraic geometry in characteristic $p$? For the sake of concreteness, and to make things more "geometric" (whatever that means), let's ...
0
votes
0
answers
49
views
Is there a correlation between the bifurcation points of dynamical system and the integral points of the elliptic curve $E_d$?
Motivated by an interest in the interplay between dynamical systems and elliptic curves also On a question of Mordell, I derived a dynamical system corresponding to the elliptic curve:
$
E_d: Y^2 = X^...
0
votes
0
answers
81
views
Computing elliptic periods from modular form
How are the periods of a modular elliptic curve computed as path integrals of its associated normalized weight 2 cusp form on the modular curve? Please provide specific paths for both periods and cite ...
8
votes
0
answers
208
views
Elliptic curves of rank 1 over number fields
I am interested what is known about the following statement:
For every number field $K$, there exists an elliptic curve $E$ defined over $K$ with algebraic rank equal to $1$.
Is this statement known ...
3
votes
0
answers
192
views
How can I prove this stronger version of Fedder's Criterion?
I was reading Fedder's original paper which proved what is now known as "Fedder's criterion". I noticed that the abstract stated something which is a priori stronger than what is proved in ...
0
votes
0
answers
100
views
Algebraic degrees of $j\left(\sqrt{-n}\right)$ and $j\left(\frac{1 + \sqrt{-n}}{2}\right)$ and class numbers of $Q(\sqrt{-n})$
Let $n\in\mathbb N$ be squarefree. Denote by $h(n)$ the class number of $Q(\sqrt{-n})$ and by $d_1(n)$ and $d_2(n)$ the degrees of the algebraic numbers $j\left(\sqrt{-n}\right)$ and $j\left(\frac{1 + ...
9
votes
3
answers
2k
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Characterisation for separable extension of a field
Can someone verify this for me.. or tell me what reference shows me this... is this true:
Let $k$ be a field. Then a field extension $K$ of $k$ is separable over $k$ iff for any field extension $L \...
2
votes
0
answers
234
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Elliptic curve with rank at least $6$
I was going through a research paper which proves the existence of an infinite family of rank $6$ elliptic curves over $\mathbb{Q}$ with invariant equal to $0$.
Let $k$ be a field of characteristic ...
2
votes
1
answer
345
views
Why this genus one curve over $\mathbb{F}_5$ appear to violate Hasse-Weil bound?
Working over $\mathbb{F}_5$, the affine curve $x^4+2=y^2$ has no points.
The projective curve $x^4+2y^4=z^2y^2$ has only one point $(0 : 0 : 1)$.
Both curves appear to violate Hasse-Weil bound of $4....
3
votes
1
answer
222
views
Large integral points on the quadratic twist $ D y^2=x^3+A x +B$
For integers $A,B,D$ and $D$ squarefree let $E : y^2=x^3+A x + B$
and $E_D$ be the quadratic twist of the elliptic curve $E$:
$$ E_D : D y^2=x^3+Ax +B$$
$E_D$ is isomorphic to $ E'_D : y^2=x^3+D^2 A ...
0
votes
0
answers
108
views
Isogeny classes for elliptic curves over quadratic field
Question. Is it possible for an elliptic curve $E$ over quadratic field $K$ to have two separate (yet connected) isogeny classes?
There are two $\mathbb{Z}/14\mathbb{Z}$ elliptic curves, $E_1$ and $...
2
votes
0
answers
52
views
Infinitely many coprime solutions of $F(x,y)= k(a_1 x + a_2 y)^2 z^2$?
This might be related to an open problem.
Let $F(x,y)$ be homogeneous degree 4 squarefree polynomial
with integer coefficients and
$h(x,y)=a_1 x + a_2 y$ and $\gcd(F,h)=1$ and $k$ be integer.
Consider ...
1
vote
1
answer
235
views
Are there conditions for an elliptic curve to have a quadratic $\mathbb{F}_q$-cover of the line without ramification $\mathbb{F}_q$-points?
Consider an elliptic curve $E: y^2 = f(x) := x^3 + ax + b$ over a finite field $\mathbb{F}_q$ of characteristic $> 3$. Obviously, the projection to $x$ is a quadratic $\mathbb{F}_q$-cover of the ...
8
votes
1
answer
365
views
Evidence for the equivariant BSD conjecture with higher multiplicity
Let $E/\mathbb{Q}$ be an elliptic curve and let $\rho$ be an irreducible Artin representation. Let $K_\rho/\mathbb{Q}$ be the smallest Galois extension such that $\rho$ factors through $\mathrm{Gal}(...
2
votes
1
answer
163
views
Fixed $a_p=p+1-\#E(\mathbb{F}_p)$ and $a_p \ne 0$ on an elliptic curve infinitely often for fixed curve over the rationals?
In this and this question we show that if $p=27a^2+27a+7$ is prime, then the order of the elliptic curve
$y^2=x^3+2$ modulo $p$ is either $p$ or $p+2$.
Q1 Can we unconditionally show that the order ...
2
votes
0
answers
92
views
Tate curve and components of special fibre II
Let $K$ be complete local field of characteristic $0$ with ring of integers $R=\mathcal{O}_{K}$ and residue field $k=R/\mathfrak{m}_R$ of characteristic $p>0$. Let $E/K$ be an elliptic curve of ...
2
votes
0
answers
103
views
Existence of supersingular abelian variety over $\mathbb F_p$ with $\mathcal O_E$-action where $E/\mathbb Q$ is quadratic imaginary ramified at $p$
Let $E/\mathbb Q$ be a quadratic totally imaginary number field with ring of integers $\mathcal O_E$. Let $p > 2$ be an odd prime number which ramifies in $\mathcal O_E$. Let $\mathcal P$ be the ...
1
vote
0
answers
153
views
Tate curve and components of special fibre
Let $K$ be a complete local field of characteristic $0$ with ring of integers $R=\mathcal{O}_{K}$ and residue field $k=R/\mathfrak{m}_R$ of characteristic $p>0$. Let $E/K$ be an elliptic curve of ...
0
votes
0
answers
61
views
Is generating semirandom blake256 hashes until packed points is on the curve, a safe algorithm to avoid the discrete log between the generated points?
I know there are more robust methods, but I wanted to know about this specific one
For any distinct said randomly generated point : $P_i,P_j\in \{P_1,...,P_k\}$ it should be hard to find $s$ such that ...
3
votes
1
answer
350
views
Elements of $\mathbb{F}_p$ represented by an irreducible polynomial $f(x) = x^3 +a_2 x^2 + a_1 x + a_0$, $f(x) \in \mathbb{F}_p[x]$
Let $p \equiv 1 \bmod 3$ be a prime, $\mathbb{F}_p$ be the finite field with $p$ elements, and $a_0$ be a generator of $\mathbb{F}_p^{\times}$ $(\mathbb{F}_p^{\times}$ the group of nonzero elements of ...