We classify the "quotients" of a tannakian category in which the objects of a tannakian subcategory become trivial, and we examine the properties of such quotient categories.
Keywords: gerbes, motives, tannakian categories
2000 MSC: 18D10
Theory and Applications of Categories,
 Vol. 18, 2007, 
No. 21, pp 654-664.
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