What is Michio Kaku's formula for string theory and how does it explain the fundamental nature of the universe?

Michio Kaku's formula for string theory involves tiny vibrating strings as the fundamental building blocks of the universe. These strings can explain the behavior of particles and forces in the universe at a quantum level. The theory suggests that everything in the universe is made up of these strings vibrating at different frequencies, which gives rise to the diversity and complexity of the world around us.