SMS scnews item created by Claus Fieker at Fri 10 Dec 2010 1523
Type: Seminar
Distribution: World
Expiry: 14 Dec 2010
Calendar1: 14 Dec 2010 1600-1655
CalLoc1: Carslaw 535A
Auth: claus@109.104.233.220.static.exetel.com.au (fcla9404) in SMS-WASM

Computational Algebra Seminar: Bright -- Computing Brauer-Manin obstructions

Some families of Diophantine equations, such as quadratic forms, have a very    
useful property: if an equation has solutions in the real numbers and in        
each p-adic field, then it has a rational solution. Such families of            
equations are said to satisfy the Hasse principle. In general the Hasse         
principle does not hold, but many violations are described by the so-called     
Brauer-Manin obstruction. This obstruction was first defined by Manin and is    
based on the Brauer group of the variety.  I will talk about how to compute     
the Brauer-Manin obstruction for certain classes of varieties, using many       
ingredients from algebraic geometry and number theory.