Where is Germany heading after the general election?

Germany has voted and the country will probably be governed by a grand coalition of the two weakening mainstream parties CDU/CSU and SPD for the next four years. In an interview, Prof. PhD. Dirk Lehmkuhl from the University of St.Gallen explains, among other things, where he sees the stumbling blocks for a new red-black coalition and whether the country is not inevitably heading for a further strengthening of the AfD.