2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/28952We estimate the changes in the condensate ground state energy induced by one or more "sizable" impurities. By "sizable", we mean an impurity whose size is within a few orders of magnitude of the trap size and not necessarily atomic in scale. A sizable impurity will "drill" a hole in the condensate wave function and alter the condensate energy. The question is whether this microscopic change can be detected macroscopically because of the Bose-Einstein condensation effect. We discuss the effect of impurity expulsion, condensate interactions, and the induced interaction between two impurities.8 pages, 7 figures, invited talk given at the XXII International Workshop on Condensed Matter Theories, June 1-7,1998, Vanderbilt University, to be published by Nova ScienceStatistical Mechanicstext