Multi-soliton complexes

In this paper we introduce the concept of multi-soliton complexes (MSC). A particular example of a MSC is an incoherent soliton in a multimode fiber o r in a photorefractive crystal, but there are many examples in other areas of physics. We discuss a variety of profiles of MSCs, their unusual collisi onal properties, the possibility of a MSC on a background and some other in teresting properties of MSCs. Some of their features are also shared by sin gle solitons, but there are many differences between the properties of the two types. (C) 2000 American Institute of Physics. [S1054-1500(00)00603-0].