Differences between revisions 29 and 92 (spanning 63 versions)
Revision 29 as of 2010-03-31 15:23:17
Size: 5276
Editor: SalmanBaig
Comment: minor edits
Revision 92 as of 2010-05-28 22:34:44
Size: 10454
Editor: AlysonDeines
Comment:
Deletions are marked like this. Additions are marked like this.
Line 2: Line 2:

Pictures: [[/pictures|photos from Sage Days]]
Line 13: Line 15:

== Projects ==

 * [[/lfcn-bsd|L-functions and the Birch and Swinnerton-Dyer Conjecture over function fields]]
  * ELLFF (Baig, Hall)
  * Heights (Occhipinti)
 * Sage classes for function fields
  * [[/ell-ff-class|Elliptic curve over function field class]] (Bradshaw, Occhipinti)
  * [[/curves|Global function field class / Curves over Finite Fields]] (Bradshaw, Hall, Hansen, Hess, Stein, Voloch, Michael Stoll (remote))
 * [[/mw|The Mordell-Weil group]] (descent, computing the algebraic rank, finding generators, torsion)
  * Generalizing (global function fields, ...) D. Robert's work on 2-descent over $\mathbb{F}_q(t)$
   * [[/pms|Porting]] from Magma to Sage (Moehlmann, Balakrishnan, Deines, R. Miller)
  * $p$-descent in characteristic $p$ (Ulmer, Moehlmann, Voloch, Hall)
 * [[/dmf|Drinfeld modular forms]]
  * Porting Butenuth's code to Sage (Butenuth, Stein, some Sage devs)
  * Comparing Hall's code to Butenuth's (Boeckle, Hall, Butenuth)
  * Gekeler's $\theta$ functions
 * [[/statistics|Statistics over function fields]] (Baig, Bradshaw, Hall, Hansen, S. Miller)
  * excess rank, repulsion near central point, random matrix models
  * families of quadratic twists, one parameter families
  * making data available
 * [[/cremona-tables|"Cremona's Tables" for function fields]] (Bradshaw, Stein, S. Miller, Occhipinti, Hall, Voloch)
  * enumerating isogeny classes
 * [[/small-char|Small Characteristic (2 - 7)]]
  * Boothby
 * [[/tkz-graphs|Combinatorial Graphs in Latex]]
  * Rob Beezer
 * [[/kantcython|Some experiments with Kant and Cython]]
  * Florian Hess
 * [[http://trac.sagemath.org/sage_trac/ticket/9052|Hasse invariant for elliptic curves]]
  * Felipe Voloch

=== Wireless Account ===

UW NetID: event0210

Password: 77Uw-52Kf-54Ga
Line 19: Line 59:
 * Second floor ([[http://www.shueyhouse.com/second%20floor.jpg]|layout]])
  * Master suite bedroom: C. Hall and S. Miller
 * Second floor ([[http://www.shueyhouse.com/second%20floor.jpg|layout]])
  * Master suite bedroom: K. Wilson and S. Miller
Line 22: Line 62:
  * Bedroom 3: G. Boeckle   * Bedroom 3: C. Hall
Line 26: Line 66:
  * Bedroom 1: S. Yazdani, R. Butenuth
  * Bedroom 2: T. Occhipinti, H. Brown
  * Bedroom 1: G. Moehlmann, R. Butenuth
  * Bedroom 2: T. Occhipinti
Line 31: Line 71:
 * B. Conrey  * G. Boeckle
Line 39: Line 79:
 * [[http://www.yelp.com/biz/a-abc-transportation-seattle#hrid:keLb-JbNNBPNxcvoGUwIOQ/src:search/query:car%20service|A-ABC Transportation]] offers a flat rate ($30 typically, before tip) for door-to-door car service. I (Salman) have used them multiple times, and they are my preferred transportation to/from the airport if I'm traveling by myself. They are a private car service (though they don't have the nicest fleet of cars) and are less expensive than a cab. Call 206-242-0102 for a reservation.  * [[http://www.yelp.com/biz/a-abc-transportation-seattle#hrid:keLb-JbNNBPNxcvoGUwIOQ/src:search/query:car%20service|A-ABC Transportation]] offers a flat rate ($30 typically, before tip) for door-to-door car service. I (Salman) have used them multiple times, and they are my preferred transportation to/from the airport if I'm traveling by myself. They are a private car service (though they don't have the nicest fleet of cars) and are less expensive than a cab. Call  for a reservation.
Line 41: Line 81:
 * [[http://shuttleexpress.com/seatac-airport/default.aspx|Shuttle Express]] picks up passengers at inner drive curb on the third floor of the Airport Garage Call 425-981-7000 to make a reservation.  * [[http://shuttleexpress.com/seatac-airport/default.aspx|Shuttle Express]] picks up passengers at the inner curb on the third floor of the Airport Garage. Call to make a reservation.
Line 46: Line 86:
Both the Shuey House and Hotel Deca are close to the UW campus as well as plenty of restaurants, coffee shops, etc. You will find that you can walk to nearly anything you like from the house of hotel, so a car is probably unnecessary. If you do plan on renting a car, please let me (Salman) know, and I will provide you information on parking, getting to/from the hotel, etc. Both the Shuey House and Hotel Deca are close to the UW campus as well as plenty of restaurants, coffee shops, etc. You will find that you can walk to nearly anything you like from the house or hotel, so a car is probably unnecessary. If you do plan on renting a car, please let me (Salman) know, and I will provide you information on parking, getting to/from the hotel, etc.
Line 48: Line 88:
Seattle also has a well-connected [[http://metro.kingcounty.gov/|bus]] system, which can be used if you want to get out of the University District and explore the rest of the city. Seattle also has a well-connected [[http://metro.kingcounty.gov/|bus]] system, which can be used if you want to get out of the University District and explore the rest of the city. Talk to Craig or Salman if you have any questions about riding the buses.
Line 54: Line 94:
== Tentative Participants == This is a [[http://www.washington.edu/home/maps/northcentral.html|campus map]] that shows the location of Padelford (the Math department) and Savery and Thomson Halls (where talks on Monday will be).

== Participants ==
Line 57: Line 99:
 * Jen Balakrishnan (MIT)  * Jen Balakrishnan (MIT) []
Line 59: Line 101:
 * Gebhard Boeckle (Universitat Duisburg-Essen)  * Gebhard Boeckle (Universitat Duisburg-Essen) []
Line 62: Line 104:
 * M. L. Brown (Institut Fourier)
* Ralf Butenuth (Universitat Duisburg-Essen)
 * Ralf Butenuth (Universitat Duisburg-Essen) []
Line 65: Line 106:
 * Brian Conrey (AIM)
Line 67: Line 107:
 * Mike Hansen
Line 68: Line 109:
 * Florian Hess (Technische Universitat Berlin)  * Florian Hess (Otto-von-Guericke-Universität Magdeburg) []
Line 71: Line 112:
 * Steven J Miller (Williams)
 * Thomas Occhipinti (Arizona)
 * Steven J Miller (Williams) []
 * Gerriet Moehlmann (Technische Universitat Berlin
)
 * Thomas Occhipinti (Arizona) []
Line 75: Line 117:
 * Doug Ulmer (Georgia Tech)
 * Felipe Voloch (Texas)
 * Doug Ulmer (Georgia Tech) []
 * Felipe Voloch (Texas) []
Line 78: Line 120:
 * Soroosh Yazdani (Mc-Master)  * Kevin Wilson (Princeton)
Line 80: Line 122:
== Tentative Project List == == Informal Talks ==
Line 82: Line 124:
 * Elliptic curves over function fields and their $L$-functions
 * Drinfeld modular forms
 * The Birch and Swinnerton-Dyer Conjecture over function fields
 * "Cremona's Tables" for function fields
 * Computing Mordell-Weil groups
 * Statistics over function fields
 * Guided ELLFF tour
Line 89: Line 126:
== (Tentative) Schedule == == Schedule ==
Line 94: Line 131:
|| 9:15am - 9:30am || Welcome || ||
|| 9:30am - 10:30am || Function Fields and Number Fields || ||
|| 10:30am - 11:30am || Introduction to Sage || C. Citro ||
|| 11:30am - 1:30pm || Lunch || ||
|| 1:30pm - 2:30pm || Drinfeld Modular Forms || ||
|| 2:30pm - 3:30pm || Computing Drinfeld Modular Forms || ||
|| 3:30pm - 4:00pm || Tea || ||
|| 4:30pm - 5:30pm || Open slot (BSD? Computing $E(K)$?) || ||
|| 5:30pm - 6:00pm || Organizational meeting || ||
|| 9:30am - 9:45am || Welcome and Breakfast || Savery Hall 155 || || ||
|| 9:45am - 10:45am || Function Fields and Number Fields || Savery Hall 155 || D. Ulmer || [[attachment:Ulmer-SageDays21-2010.pdf | Slides (careful ... very broadbrush)]] ||
|| 10:45am - 11:20am || An Introduction to Sage for Number Theorists || Savery Hall 155 || C. Citro || ||
|| 11:30am - 1:30pm || Lunch || || || ||
|| 1:30pm - 2:30pm || Drinfeld Modular Forms and Harmonic Cocycles || Thomson Hall 231 || G. Boeckle || [[attachment:Boeckle-SageDays21-2010.pdf | Slides]] ||
|| 2:30pm - 3:30pm || Computing Drinfeld Modular Forms || Thomson Hall 231 || R. Butenuth || [[attachment:Butenuth-SageDays21-2010.pdf | Slides]] ||
|| 3:30pm - 4:30pm || Tea || [[http://art.washington.edu/66_Parnassus|Parnassus]] || || ||
|| 4:30pm - 5:30pm || Calculating L-functions over F_q(t) || Savery Hall 139 || C. Hall || ||
|| 5:30pm - 6:30pm || Organizational meeting || Savery Hall 139 || || ||
|| 7:30pm - 9pm'ish || Dinner || Piatti (U-Village) || || ||

Please let me know as soon as possible if you will be able to attend the dinner on Monday night for the group.

=== William's Sage Class ===

William will talk about "how to do Sage development" in his [[http://wiki.wstein.org/10/480b|undergraduate Sage class]] on Wednesday and Friday:

  * Wednesday at 1:30pm in Mueller Hall 153: http://www.washington.edu/maps/?l=MU
  * Friday at 1:30pm in Mueller Hall 153: http://www.washington.edu/maps/?l=MU



==== Talk Abstracts ====

Function Fields and Number Fields (Ulmer): I will try to explain some of the analogies between arithmetic in these two domains and also why we can often do more in the function field setting.

An Introduction to Sage for Number Theorists (Citro): I will give a short introduction to Sage, highlighting aspects that are particularly relevant for number theory. You are welcome to come armed with questions, especially of the "can Sage do <insert your
favorite thing here>" variety.

Drinfeld Modular Forms and Harmonic Cocycles (Boeckle): In this talk I shall introduce the main concepts needed to understand
Drinfeld cusp forms and the combinatorics that allows their computation: The Bruhat-Tits tree, Drinfeld's symmetric space, the cusp forms and harmonic cocycles. I shall state many of the basic theorems including some of Teitelbaum's work relating Drinfeld cusp forms and harmonic cocycles. I will also present a (very incomplete and subjective) list of open questions.

Computing Drinfeld Modular Forms (Butenuth): Drinfeld modular forms can be related to harmonic cochains, which are functions on the edges of the Bruhat-Tits tree fulfilling certain properties. In my talk I will try to explain how to relate Drinfeld modular forms to these objects and how to explicitly compute Hecke operators on them. The slides to the talk can be downloaded [[attachment:Slides_Ralf.pdf | here]].

Calculating L-functions over F_q(t) (Hall): We discuss solutions to the problem of computing the L-function of a non-constant elliptic curve E/F_q(t). Concretely it is a polynomial with coefficients in Z and can be computed in O(q^m) operations for some integer m=m(E) depending on E. The naive approach via point counting works but at the expense of a 'large' m(E). However, given enough information about one E/F_q(t), the relative cost of computing a 'related' elliptic curve's L-function is smaller. One can consider a quadratic twist or, more generally, a 'pullback' and the 'primitive' part of its L-function. We'll elaborate on these themes in the talk and introduce a library we are developing for calculating L-functions.
Line 117: Line 180:

== Reading List ==

A reading list can be found [[/readinglist|here]] where participants can add items as well.

Sage Days 21: Function Fields

Pictures: photos from Sage Days

Logistics

Organizers: William Stein, Chris Hall, Craig Citro, Salman Baig

Location: The Shuey House, 5218 16th Ave NE, Seattle, WA 98105

Dates: May 24 - 28, 2010 (check in on May 23rd after 4:00pm, check out on May 29th by 10:30am)

Mailing list: Group page.

Projects

Wireless Account

UW NetID: event0210

Password: 77Uw-52Kf-54Ga

Housing

A handful of visitors will be staying at the Shuey House, while the remaining visitors have rooms on hold for them at Hotel Deca (4507 Brooklyn Avenue NE, Seattle, WA 98105). The tentative housing arrangement is as follows:

The Shuey House

  • Second floor (layout)

    • Master suite bedroom: K. Wilson and S. Miller
    • Bedroom 2: J. Balakrishnan
    • Bedroom 3: C. Hall
    • Bedroom 4: F. Hess
  • Third Floor (layout)

    • Bedroom 1: G. Moehlmann, R. Butenuth
    • Bedroom 2: T. Occhipinti

Hotel Deca

  • G. Boeckle
  • D. Ulmer
  • F. Voloch

Getting to the Shuey House/Hotel Deca from Seattle-Tacoma

Here are some options to get to the Shuey House or Hotel Deca from the airport:

  • A-ABC Transportation offers a flat rate ($30 typically, before tip) for door-to-door car service. I (Salman) have used them multiple times, and they are my preferred transportation to/from the airport if I'm traveling by myself. They are a private car service (though they don't have the nicest fleet of cars) and are less expensive than a cab. Call for a reservation.

  • Taxis from the airport cost about $40 (before tip) and can be found by following the signs in the airport.
  • Shuttle Express picks up passengers at the inner curb on the third floor of the Airport Garage. Call to make a reservation.

  • There is a new light-rail service from the airport to downtown Seattle, but you will then need to take a taxi to the house/hotel (about 5 miles north of downtown). This is not a good option unless you want to spend time in downtown Seattle.

Getting Around

Both the Shuey House and Hotel Deca are close to the UW campus as well as plenty of restaurants, coffee shops, etc. You will find that you can walk to nearly anything you like from the house or hotel, so a car is probably unnecessary. If you do plan on renting a car, please let me (Salman) know, and I will provide you information on parking, getting to/from the hotel, etc.

Seattle also has a well-connected bus system, which can be used if you want to get out of the University District and explore the rest of the city. Talk to Craig or Salman if you have any questions about riding the buses.

Map

Here's a Google map with the major locations marked.

This is a campus map that shows the location of Padelford (the Math department) and Savery and Thomson Halls (where talks on Monday will be).

Participants

  • Salman Baig (Washington)
  • Jen Balakrishnan (MIT) []
  • Rob Beezer (Univ of Puget Sound)
  • Gebhard Boeckle (Universitat Duisburg-Essen) []
  • Tom Boothby (Washington)
  • Robert Bradshaw (Washington)
  • Ralf Butenuth (Universitat Duisburg-Essen) []
  • Craig Citro (Washington)
  • Alyson Deines (Washington)
  • Mike Hansen
  • Chris Hall (Wyoming)
  • Florian Hess (Otto-von-Guericke-Universität Magdeburg) []
  • Jacob Lewis (Washington)
  • Robert Miller (Washington)
  • Steven J Miller (Williams) []
  • Gerriet Moehlmann (Technische Universitat Berlin)
  • Thomas Occhipinti (Arizona) []
  • Dan Shumow (Washington)
  • William Stein (Washington)
  • Doug Ulmer (Georgia Tech) []
  • Felipe Voloch (Texas) []
  • Wenhan Wang (Washington)
  • Kevin Wilson (Princeton)

Informal Talks

  • Guided ELLFF tour

Schedule

We will have one full day of organized talks, followed by working sessions and status reports the rest of the week. Informal talks are also welcome and will be left to individuals and working groups to organize.

Monday, May 24

9:30am - 9:45am

Welcome and Breakfast

Savery Hall 155

9:45am - 10:45am

Function Fields and Number Fields

Savery Hall 155

D. Ulmer

Slides (careful ... very broadbrush)

10:45am - 11:20am

An Introduction to Sage for Number Theorists

Savery Hall 155

C. Citro

11:30am - 1:30pm

Lunch

1:30pm - 2:30pm

Drinfeld Modular Forms and Harmonic Cocycles

Thomson Hall 231

G. Boeckle

Slides

2:30pm - 3:30pm

Computing Drinfeld Modular Forms

Thomson Hall 231

R. Butenuth

Slides

3:30pm - 4:30pm

Tea

Parnassus

4:30pm - 5:30pm

Calculating L-functions over F_q(t)

Savery Hall 139

C. Hall

5:30pm - 6:30pm

Organizational meeting

Savery Hall 139

7:30pm - 9pm'ish

Dinner

Piatti (U-Village)

Please let me know as soon as possible if you will be able to attend the dinner on Monday night for the group.

William's Sage Class

William will talk about "how to do Sage development" in his undergraduate Sage class on Wednesday and Friday:

Talk Abstracts

Function Fields and Number Fields (Ulmer): I will try to explain some of the analogies between arithmetic in these two domains and also why we can often do more in the function field setting.

An Introduction to Sage for Number Theorists (Citro): I will give a short introduction to Sage, highlighting aspects that are particularly relevant for number theory. You are welcome to come armed with questions, especially of the "can Sage do <insert your favorite thing here>" variety.

Drinfeld Modular Forms and Harmonic Cocycles (Boeckle): In this talk I shall introduce the main concepts needed to understand Drinfeld cusp forms and the combinatorics that allows their computation: The Bruhat-Tits tree, Drinfeld's symmetric space, the cusp forms and harmonic cocycles. I shall state many of the basic theorems including some of Teitelbaum's work relating Drinfeld cusp forms and harmonic cocycles. I will also present a (very incomplete and subjective) list of open questions.

Computing Drinfeld Modular Forms (Butenuth): Drinfeld modular forms can be related to harmonic cochains, which are functions on the edges of the Bruhat-Tits tree fulfilling certain properties. In my talk I will try to explain how to relate Drinfeld modular forms to these objects and how to explicitly compute Hecke operators on them. The slides to the talk can be downloaded here.

Calculating L-functions over F_q(t) (Hall): We discuss solutions to the problem of computing the L-function of a non-constant elliptic curve E/F_q(t). Concretely it is a polynomial with coefficients in Z and can be computed in O(q^m) operations for some integer m=m(E) depending on E. The naive approach via point counting works but at the expense of a 'large' m(E). However, given enough information about one E/F_q(t), the relative cost of computing a 'related' elliptic curve's L-function is smaller. One can consider a quadratic twist or, more generally, a 'pullback' and the 'primitive' part of its L-function. We'll elaborate on these themes in the talk and introduce a library we are developing for calculating L-functions.

Tuesday, May 25

Free day to work or organize talks.

Wednesday, May 26

11:00am - 12:00pm

Status reports

Shuey House

Thursday, May 27

Free day to work or organize talks.

Friday, May 28

11:00am - 12:00pm

Final status reports

Shuey House

Reading List

A reading list can be found here where participants can add items as well.

daysff (last edited 2010-05-28 22:34:44 by AlysonDeines)