English

The Zeldovich number: A universal dimensionless measure for the electromagnetic field

Quantum Physics 2023-07-06 v2

Abstract

In this work we extend the Zeldovich formula, which was originally derived for the free electromagnetic field and was interpreted as the number of photons. We show that our extended formula gives a universal dimensionless measure of the overall strength of electromagnetic fields: free fields and fields produced by various sources, in classical and in quantum theory. In particular, we find that this number (the Zeldovich number) for macroscopic systems is huge, of the order of 102010^{20}. For the hydrogen atom in the ground state it is equal to 0.025 and for the xenon atom it is around 50.

Keywords

Cite

@article{arxiv.2303.12183,
  title  = {The Zeldovich number: A universal dimensionless measure for the electromagnetic field},
  author = {Iwo Bialynicki-Birula and Zofia Bialynicka-Birula},
  journal= {arXiv preprint arXiv:2303.12183},
  year   = {2023}
}

Comments

Submitted to the special issue of MDPI Atomic Physics in Memory of Francesco Persico