# Quantum field theory treatment of magnetic effects on a system of free electrons

## TL;DR

This paper uses quantum field theory to analyze how magnetic fields influence the energy and spin of free electrons, highlighting differences from classical and quantum mechanics and discussing implications for biological systems.

## Contribution

It provides a quantum field theoretical framework for magnetic effects on free electrons, offering simplified formulas for moderate fields and slow electrons, and compares these with classical and quantum approaches.

## Key findings

- Derived simple formulae for magnetic effects on electrons in moderate fields
- Identified key differences between quantum field theory and classical/quantum mechanics
- Discussed potential implications for biological electron systems

## Abstract

The effects of a magnetic field on the energy and on the spin of free electrons are computed in the framework of quantum field theory. In the case of a constant moderate field and with relatively slow electrons, the derived formulae are particularly simple. A comparison with the approaches of classical physics and of quantum mechanics shows essential differences and important analogies. The relevance to the magnetic effects of the initial polarization components of the electron states and the possible existence of special values of these quantities are discussed in the final conclusions, which might be useful to explain recent experiments on quasi-free electrons in chiral systems in biology.