Introduction to Smith's Methods

Peter Koymans will visit the University of Bristol from 13th-24th April 2026, during which time he will give a lecture series on the powerful methods first introduced by Alexander Smith to tackle the Cohen--Lenstra--Gerth conjecture on class groups of imaginary quadratic fields and Goldfeld's conjecture on quadratic twists of elliptic curves.

Practical details

Speaker: Peter Koymans
Abstract: See abstract
Dates: Monday 13th April — Friday 24th April 2026.
Location: Fry Building, University of Bristol.
Organisers:  Ross Paterson and Happy Uppal.

Please note:  for non-Bristol based academics, participation is by application only.  Please contact the organisers if you need a link to the application form.

Materials

Please note that the exercise sheets can easily take more than 2 hours (and this is on purpose), no-one is expected to solve all of the exercises during the allotted time slots!  Participants may wish to look at the primer and have a go at sheet 1 before the event.  Exercise sheet 1 below is an exercise sheet of Matthew Emerton from a course in 2012.

Primer: Galois cohomology primer
Exercise sheets: Exercise sheet 1Exercise sheet 2Exercise sheet 3Exercise sheet 4
Notes: Live notes

Schedule

If for any reason you need a break and would appreciate a quiet space, please let the organisers know and we will find you a private space.  Below the weekly schedules, we list some additional booked spaces for quiet working use only.

Week 1
Time Monday
Tuesday Wednesday Thursday Friday
09:00 - 10:00 Lecture 2
(2.04)
Working time (2.04)
10:00 - 11:00 Lecture 1
(2.04)
Lecture 3
(2.04)
Exercises 3
(G.07)
11:00 - 12:00 Tea/ Discussion Working time (G.07)
12:00 - 13:00 Lunch Lunch Lunch Lunch Lunch
13:00 - 14:00
14:00 - 15:00 Exercises 1
(G.07)
Exercises 2
(G.07)
Working time (G.07) Working time (2.32) Working time (G.07)
15:00 - 16:00 Working time (G.07) Working time (G.07)
16:00 - 17:00 Heilbronn Seminar
Week 2
Time Monday
Tuesday Wednesday Thursday Friday
09:00 - 10:00 Lecture 4 (2.04) Informal talk (2.04)
10:00 - 11:00 Catch-up session
(2.04)
Lecture 5
(2.04)
11:00 - 12:00 Tea/ Discussion Linfoot Seminar
12:00 - 13:00 Lunch Lunch Lunch Lunch Lunch
13:00 - 14:00
14:00 - 15:00 Colloquium tea@ 14:30
(Common room)
Exercises 4
(G.07)
Working time (G.07) Open Problems
(G.07)
15:00 - 16:00 Colloquium Working time (G.07) Working time (G.07)
16:00 - 17:00 Wine Reception Heilbronn Seminar
Additional room bookings

The rooms below are for quiet working only.

  • Monday 13th April: 1200 - 1700 (G.14)
  • Tuesday 14th April: 1200 - 1700 (2.82)
  • Wednesday 15th April: 1600 - 1700 (2.32)
  • Friday 17th April:  1100 - 1200 (2.04), 1200 - 1700 (2.32)
  • Tuesday 21st April: 1600 - 1700 (2.32)
  • Wednesday 22nd April: 1500 - 1700 (2.32)
  • Thursday 23rd April: 1300 - 1700 (2.32)

Acknowledgements

This event is funded by the Heilbronn International Visitor scheme, hosted at the University of Bristol.