There are hundreds of billions of galaxies in the universe. These galaxies can be broadly divided into dwarf galaxies with less than a billion stars and giant galaxies with more than a billion stars. The most widely used classification of giant galaxies is the "Hubble sequence" proposed by American astronomer Edwin Hubble in 1926, which lists four types: elliptical galaxies, spiral galaxies, barred spiral galaxies, lenticular galaxies, and irregular galaxies. As can be seen from the diverse shapes of galaxies, it is thought that various factors are involved in the formation of galaxies. However, there must be a basic principle by which a group of more than a billion stars forms. In this study, we considered the formation of galaxies by extending the formation of stars, gravitational fields, and dark energy fields according to the Energy Body Theory. As a result, we found that the reason why spiral galaxies, which account for 60% of galaxies, have a spiral shape is fundamentally due to the rotation of the galaxy and the expansion of the dark energy field. The spiral arms were formed when a small group of stars rotating in the counter-rotating direction near the bulge approached the bulge, causing them to unravel and extend along the arms. It is also thought that energy flows into the spiral of the dark energy field from the outside, forming a high-energy space. However, it remains to be seen whether this theory is superior to the "high density wave theory," the mainstream explanation for spiral arms. The flatness of the rotation speed of spiral galaxies, an important issue in astrophysics, is thought to be caused by the neutralization due to synthesis of the spiral of the galaxy when the gravitational field is formed, and the rotation according to Kepler's laws.