ABSTRACT: First, we develop the multi-connected topological economics to the multi-connected topological sociology, etc. Next, we research the social field (including general relativity) and some applications. Third, the complex analysis is discussed. Fourth, variational calculus is studied. Fifth, we search nonlinearity and a new mathematical relation in social sciences. The multi-connected topology, general relativity and other mathematical ways will open new windows for investigations of economy and sociology, etc.
KEY WORDS:social science, economics, sociology, topology, field, complex analysis, variational calculus, general relativity.