Unified field theory is a theoretical framework that attempts to explain the fundamental forces of nature - gravity, electromagnetism, and the strong and weak nuclear forces - as different aspects of a single, unified field. One of the most promising approaches to a unified field theory is string theory, which posits that the basic building blocks of the universe are not point-like particles but tiny, one-dimensional strings that vibrate at different frequencies to produce the various particles

Light Falls: Einstein's Theory of Relativity