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== Computing root numbers project ==
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1. Silverman I Chapter VII (does not mention root numbers but gives background information to compute them) 1. Silverman I Chapter VII (does not mention root numbers but gives background information to compute them) - reduction types of elliptic curves etc.
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Elliptic Curves over \QQ Elliptic Curves over $\QQ$
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root number w = \prod_p w_p * w_{\infinity} root number $w = \prod_p w_p$ * $w_\infty$
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p is a prime of good reduction iff p \nmid discriminant.
If E has good reduction at p then w_p = +1.
p is a prime of good reduction iff $p \nmid$ discriminant.
If E has good reduction at p then $w_p = +1$.
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p \mid \mid means p is a prime of multiplicative reduction
If E has split multiplicative reduction then w_p = -1
If E has non-split multiplicative reduction then w_p +1
$p \mid \mid N$ means p is a prime of multiplicative reduction
If E has split multiplicative reduction then $w_p = -1$
If E has non-split multiplicative reduction then $w_p = +1$
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Step 1: implement w for E/\QQ with N square-free (already done in GP)
If
Step 1: implement w for $E/\QQ$ with N square-free (already done in GP)
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If p^2\mid N then p is a prime of additive reduction for E and w_p is more complicated. There are formulae to compute them, they rely on Tate's algorithm. If $p^2\mid N$ then p is a prime of additive reduction for E and $w_p$ is more complicated. There are formulae to compute them, they rely on Tate's algorithm.
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w = \prod_p w_p \prod_{v\div \infinity} (-1) w = $\prod_p w_p \prod_{v\div \infinity} (-1)$
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w_p for p \nmid 2,3 has been done by Rohrlich (somewhat hard to read) see Theorems 2 and 3 which are self-contained $w_p for p \nmid 2,3$ has been done by Rohrlich (somewhat hard to read) see Theorems 2 and 3 which are self-contained
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for p \mid 3 this has been done Kobayashi for $p \mid 3$ this has been done Kobayashi

Tim Dokchitser (Cambridge University): Complex L-functions and the Birch and Swinnerton-Dyer conjecture

Structure of the course

  • Quick review of Elliptic curves over Q and the Mordell-Weil theorem
  • Elliptic curves over finite fields, heuristics for their distribution and the naive version of BSD
  • L-functions of elliptic curves and the BSD-conjecture
  • Root numbers and how to compute them
  • Parity predictions, Goldfeld's conjecture and ranks of elliptic curves over number fields

Prerequisites

Some familiarity with basic algebraic number theory (number fields, primes), and having seen elliptic curves

Background reading

J. H. Silverman, "The arithmetic of elliptic curves", Chapters 3, 7 and 8.

Sage Reference Manual on elliptic curves: http://sagemath.org/doc/reference/plane_curves.html, up to `Isogenies'.

Computational projects

There will be many small problems and larger assignments to play with, illustrating all the concepts and conjectures from the course.

A. Root Numbers over K for elliptic curves (implement)

  • People: Armin, Charlie, Hatice, Christ, Lola, Robert Miller, Thilina, M. Tip, Robert Bradshaw

B. #III(E/K)_{an} function (L-functions, connection to Wuthrich)

  • People: Berinder, M. Tip, Adam, Robert Miller, Robert Bradshaw, Chris Wuthrich

C. Parity Predictions

  • People: Arijit, Anil, Adam

Computing root numbers project

References: 1. Silverman I Chapter VII (does not mention root numbers but gives background information to compute them) - reduction types of elliptic curves etc.

Elliptic Curves over \QQ

root number w = \prod_p w_p * w_\infty

p is a prime of good reduction iff p \nmid discriminant. If E has good reduction at p then w_p = +1.

p \mid \mid N means p is a prime of multiplicative reduction If E has split multiplicative reduction then w_p = -1 If E has non-split multiplicative reduction then w_p = +1

Step 1: implement w for E/\QQ with N square-free (already done in GP)

If p^2\mid N then p is a prime of additive reduction for E and w_p is more complicated. There are formulae to compute them, they rely on Tate's algorithm.

Elliptic Curves over general number fields

Root number classification

w = \prod_p w_p \prod_{v\div \infinity} (-1)

Additive reduction w_p for p \nmid 2,3 has been done by Rohrlich (somewhat hard to read) see Theorems 2 and 3 which are self-contained

for p \mid 3 this has been done Kobayashi

for p \mid 2 T & V Dokchitser the formulae are really hard - ignore this (!!)

Would perhaps be better to do for any p, or even determine w globally (T & V Dokshitser: page 1) There is a decision to be made as to which methods to use.

days22/dokchitser (last edited 2010-08-10 11:30:48 by Armin Straub)