Clifford Johnson is a professor and an expert in the fields of physics and astronomy.We often have to study the very, very small to figure how the universe works. Here's a great TED-Ed Lesson about the small parts of the beginning of the universe.String theory is an active research framework in particle physics that attempts to reconcile quantum mechanics and general relativity. It is a contender for a theory of everything (TOE), a self-contained mathematical model that describes all fundamental forces and forms of matter. String theory posits that the elementary particles (i.e., electrons and quarks) within an atom are not 0-dimensional objects, but rather 1-dimensional oscillating lines ("strings").Here's a TED Talk where physicist Brian Greene talks about the multiverse. Here, Greene explains superstring theory, the idea that miniscule strands of energy vibrating in 11 dimensions create every particle and force in the universe.Astrophysicist Neil deGrasse Tyson teases theoretical physicist Brian Greene about the slow progress of string theory. This is from the 2011 Isaac Asimov Memorial Debate where leading voices in science debated the question: Can the entire universe be explained with a single unifying theory?Here's an interesting interview with Neil deGrasse Tyson.This is a video about the two camps: Einstein's theory of general relativity and string theory.