FERMIONIC AND BOSONIC BUBBLES AND FOAM a
/ Authors
/ Abstract
The positioning of one or more bubbles inside a many fermion or boson system,does not affect the volume, surface or curvature terms in the liquid drop expansionof the total energy. If Coulomb effects are irrelevant, the only contribution tothe ground state energy of a system with one or more voids arises from quantumeffects, which is similar to the Casimir effect in vacuum or in critical phenomena.We discuss the characteristics of such systems, the interplay among various effects,such as shell corrections and chaotic behavior, and briefly mention the role of thetemperature and pairing.