Coproducts in categories of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" id="d1e22" altimg="si8.svg"><mml:mi>q</mml:mi></mml:math>-matroids

q-Matroids form the q-analogue of classical matroids. In this paper we introduce various types maps between q-matroids. These are not necessarily linear, but they map subspaces to and respect q-matroid structure in certain ways. The give rise different categories We show that only one these possesses a coproduct. This is category where morphisms linear weak maps, is, rank image any subspace larger than itself. coproduct very recently introduced direct sum