Is zeropoint energy physical? A toy model for Casimirlike effect
Abstract
Zeropoint energy is generally known to be unphysical. Casimir effect, however, is often presented as a counterexample, giving rise to a conceptual confusion. To resolve the confusion we study foundational aspects of Casimir effect at a qualitative level, but also at a quantitative level within a simple toy model with only 3 degrees of freedom. In particular, we point out that Casimir vacuum is not a state without photons, and not a ground state for a Hamiltonian that can describe Casimir force. Instead, Casimir vacuum can be related to the photon vacuum by a nontrivial Bogoliubov transformation, and it is a ground state only for an effective Hamiltonian describing Casimir plates at a fixed distance. At the fundamental microscopic level, Casimir force is best viewed as a manifestation of van der Waals forces.
 Publication:

Annals of Physics
 Pub Date:
 August 2017
 DOI:
 10.1016/j.aop.2017.05.013
 arXiv:
 arXiv:1702.03291
 Bibcode:
 2017AnPhy.383..181N
 Keywords:

 Zeropoint energy;
 Vacuum;
 Casimir effect;
 van der Waals force;
 Quantum Physics;
 Condensed Matter  Other Condensed Matter;
 High Energy Physics  Theory
 EPrint:
 21 pages, version accepted for publication in Annals of Physics