If you don't mind a little math, I found this paper by one of the principals in the area (Deift) to provide more background: http://www.icm2006.org/proceedings

If you don't mind a little math, I found this paper by one of the principals in the area (Deift) to provide more background: http://www.icm2006.org/proceedings/Vol_I/11.pdf http://www.icm2006.org/proceedings/Vol_I/11.pdf