Much ado about nothing

Nature abhors a vacuum, the ancient physicists told us. And judging from the modern quantum theory of the vacuum it is not very surprising. Indeed, since Dirac propounded his theory of the electron, there have appeared many papers in which the properties of the vacuum have been discussed in terms of very complicated (and sometimes divergent) integrals. Instead of being the simplest problem in the world, the motion of a free electron in a vacuum appears to be an extremely complicated phenomenon. Instead of being an elementary nothingness, like the antithesis of Hegel's “Being” or that which Torricelli would have produced with a perfect pump, the vacuum of quantum electrodynamics can “fluctuate”, can be “polarized”, and can contain “negative energy electrons”. What is worse, its fluctuations and polarization are infinite and the number of negative energy electrons is infinite also.