SCL's Antun Balaz and Ivana Vidanovic participated in the 2009 Arnold Sommerfeld Summer School on Condensed Matter Physics with Ultracold Quantum Gases. The school was organized from 12. to 16. October 2009 at the Arnold Sommerfeld Center for Theoretical Physics of the Ludwig-Maximilians University (LMU) in Munich by Immanuel Bloch, Stefan Kehrein, Axel Pelster, Ulrich Schollwöck, and Jan von Delft.

During the poster session, SCL researchers presented some of the results obtained within the bilateral project PI-BEC: Ivana Vidanovic presented a poster entitled "Numerical Study of BEC Phase Transition in Hartree-Fock Approximation", while Antun Balaz presented the poster on "Exact Numerical Study of Rotating Ideal Bose-Einstein Condensates". In a useful discussion with Ulrich Schollwöck possible application of the short-time effective action approach in the framework of the finite-temperature density matrix renormalization group (DMRG) was considered, as well as the use of recently introduced linear time-series prediction method [Barthel, Schollwöck, White, PRB 79, 245101 (2009)] in numerical studies of BEC systems.

In several lively discussions with Axel Pelster the ongoing research developments within the PI-BEC project were reviewed: Hartree-Fock-Bogoliubov approximation for BEC and related numerical studies, effective action approach for time-dependent potentials, and numerical treatment of parametric resonance effects on collective oscillation modes of ultracold Bose gases. Extension of the effective action approach to optical lattice models was also considered.