['Section', '2', 'considers', 'the', 'implications', 'of', 'the', 'coupling', 'between', 'the', 'spin', 'of', 'a', 'classical', 'electron', 'and', 'the', 'rapidly', 'varying', 'electromagnetic', 'field', 'produced', 'by', 'a', 'laser', '-', 'driven', 'plasma', 'wave', '.']