Convolution bialgebra of a Lie groupoid and transversal distributions

Abstract

For a Lie groupoid G over a smooth manifold M we construct the adjoint action of the étale Lie groupoid G# of germs of local bisections of G on the Lie algebroid g of G. With this action, we form the associated convolution Cc∞(M)/R-bialgebra Cc∞(G#,g). We represent this Cc∞(M)/R-bialgebra in the algebra of transversal distributions on G. This construction extends the Cartier-Gabriel decomposition of the Hopf algebra of distributions with finite support on a Lie group.