Shrawan Kumar is John R. and Louise S. Parker Distinguished Professor of Mathematics at the University of North Carolina, Chapel Hill. He was an invited Speaker at the 2010 International Congress of Mathematicians and was elected a Fellow of the American Mathematical Society in 2012. This is his third book.
'The author succeeds in giving a masterful, clear, motivated and practically up to date presentation of a subject which is connected to the forefront of the mathematical research. It is addressed both to those researchers who just enter the subject and to those already active in theoretical physics, algebraic geometry, representation theory. This admirable book (which is the third book of Shrawan Kumar) is the first one about a very advanced and technical subject and it will be surely a standard reference.' Nicolae Manolache, zbMATH