This research delves into how electron-photon showers behave in the fields of aligned single crystals by coming up with a theory. They found that at very high energies and thresholds, the cascade processes in crystal axes need special consideration (hard cascade). By working out equations, they figured out how this hard cascade functions. As the energy threshold drops, other processes like Beth-Heitler on individual nuclei also come into play (mixed and soft cascades), which they simulated on computers. The researchers then looked at experiments on radiation and pair creation in aligned crystals to show the results.