Thanks to everyone who joined our live chat with physicist and 2057 host Michio Kaku on Jan. 28, 2007.

READ THE CHAT TRANSCRIPT.

Michio Kaku is a theoretical physicist, tenured professor and co-creator of string field theory, a branch of string theory. Kaku received a B.S. (summa cum laude) from Harvard University in 1968. He went on to the Berkeley Radiation Laboratory at the University of California, Berkeley and received a Ph.D. in 1972. In 1973, he held a lectureship at Princeton University.

In addition to holding the Henry Semat Chair and Professorship in theoretical physics at City College of New York, he has taught there for more than 25 years. Presently, he is engaged in working on Einstein's "Theory of Everything," seeking to unify the four fundamental forces of the universe: the strong force, the weak force, gravity and electromagnetism. Additionally, he has been a visiting professor at the Institute for Advanced Study in Princeton, as well as at New York University.

Dr. Kaku is the author of several scholarly textbooks and has had more than 70 articles published in physics journals covering topics such as superstring theory, supergravity, supersymmetry and hadronic physics. He is also known as an author of popular science books, including the best-sellers Beyond Einstein, Visions: How Science Will Revolutionize the 21st Century, Hyperspace and Parallel Worlds.

Dr. Kaku hosts two radio programs: "Explorations," heard on many independent radio stations and "Science Fantastic," the only nationally syndicated science program on commercial radio in the United States.

Dr. Kaku has become a popular figure in mainstream media, due to his knowledge and accessible approach to explaining complex physics, quantum mechanics and other topics. His television appearances include the Larry King Show, Nightline, PBS' Nova and Innovation, 60 Minutes, Good Morning America  and CNN News. He has been featured on science documentaries from the Discovery Channel, BBC and SciFi Channel.