SCL's Antun Balaz was invited to give a talk at the 6th Mathematical Physics Meeting: Summer School and Conference on Modern Mathematical Physics (MPHYS6), organized jointly by the Institute of Physics Belgrade and Faculty of Mathematics, University of Belgrade. In a lecture entitled "Path Integrals Without Integrals", he presented main results in the development of short-time effective action approach, obtained in collaboration with Ivana Vidanovic, Aleksandar Bogojevic, Aleksandar Belic and Axel Pelster. Recent applications of this method to numerical study of fast-totating Bose-Einstein condensates were also briefly presented in the talk.