Abstract

Milnor produced his famous link homotopy invariants by studying the fundamental group of the link complement.  Edge homotopy (EH) is a generalization of link homotopy for spatial graphs, but so far, it has been difficult to produce an analogue of Milnor invariants for all spatial graphs.  We will study a relation on spatial graphs called "component homotopy" (CH), and produce Milnor-type algebraic invariants.  Since EH implies CH, these invariants are also edge homotopy invariants.