The Casimir Effect
A full lecture reconstruction of the Casimir effect, following the original lecture's development from vacuum wave functionals and vacuum fluctuations to regularization, Euler–Maclaurin analysis, the large-plate asymptotics, and the final Casimir pressure formula.
Introduction
The Casimir effect is one of the clearest demonstrations that vacuum fluctuations in quantum field theory are not just formal baggage. They can lead to measurable physical forces. But to understand the effect properly, one has to be careful about two things at once.
First, the vacuum of a quantum field is not empty in the classical sense. Even in the ground state, field modes have
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