Figure 1. Feynman diagram: the interaction of two electrons of virtual phonons

From

How the Cycle of Scientific Knowledge is Reflected in the Course of Solid State Physics: the Effect of Magnetic Flux Quantization

N. Podoprygora, A. Tkachenko

American Journal of Educational Research. 2014, 2(12B), 61-69 doi:10.12691/education-2-12B-12