We give a geometric categorification of the Verma modules M (λ) for quantum sl2.
ContentsFrom the work of Lauda in [34,35] adjusted to our context it follows that for each n 0 there is an action of the nilHecke algebra NH n on F n and on E n . As a matter of fact, there is an enlargement of NH n , which we denote as A n , acting on F n and E n , also admitting a nice diagrammatic description (see § 1.1.6 for a sketch).We define M as the direct sum of all the categories M k and functors F, E and Q in the obvious way. One of the main results in this paper is the following. † All our functors are, in fact, superfunctors which we tend to see as functors between categories endowed with a Z/2Z-action, whence the use of the terminology functor. ‡ We thank Aaron Lauda for explaining this to us.