This is kind of a cool and nerdy read, over at MayaStation they posted a pdf of the Maya Nucleus white paper – everything you wanted to know about Maya’s nucleus solver.
“Maya has several nodes (such as the Nucleus, Maya nCloth and Maya nParticle nodes) that help act as interfaces to the Nucleus solver, setting up relationships and translating data to and from Nucleus. This not only helps allow better interaction between different entities, but also takes advantage of stable solve and collision capabilities inherent in Nucleus.
This document discusses the internal solver architecture, and how the components of the solver are controlled through the Maya nodes and attributes. This is followed by a more detailed discussion on how to help achieve optimal results with Maya nCloth and nCloth caching, and some frequently used effects.
Much of this document will deal with the cloth application of Nucleus; however, nParticles can be considered a subset of nCloth in terms of Nucleus. Particles may be considered like cloth objects that have no bend or stretch resistance and vertex collisions and constraints only.”
