Time for some fairly deep physics -- strap yourselves in! For many decades, notions of a "theory of everything" have floated around scientific circles: can the universe be explained by a "unified theory," in other words a theory that unifies the theories of general relativity and quantum mechanics? Each of these theories works well in their realms (the very big and the very small), but trying to tie them together doesn't work easily. String theory is one of several possible ways to do this -- but there are others, and they all lack much in the way of testable proof. Some scientists continue to think that a unified theory is impossible.

On March 7, 2011, a six-member panel of scientists joined Neil deGrasse Tyson to discuss that elusive "theory of everything." For about an hour and a half, this distinguished group tears it up:

Dr. Katherine Freese, professor of physics at the University of Michigan

Dr. Jim Gates, professor of physics at the University of Maryland-College Park

Dr. Janna Levin, professor of physics and astronomy at Barnard College

Dr. Marcello Gleiser, professor of physics and astronomy at Dartmouth College

Dr. Brian Greene, professor of physics and mathematics at Columbia University

Dr. Lee Smolin, theoretical physicist at Perimeter Institute for Theoretical Physics

Topics: a report from Brian Greene on string theory (ten years after the first such panel), a discussion of the core problem(s) at hand, chirality, data is always just a year away, balloons, Flatland, gravitons, Adinkra symbols, and many other topics. To paraphrase what reader James said earlier this week in suggesting this discussion, the most bizarre and engaging part of this talk is when Dr. Gates raises the possibility that we all may indeed live in some form of The Matrix and are ourselves basically just mathematical/computer code. Want to know what's up with that? Watch.

For: science/physics nerds. The talk is aimed at the layman, though it may seem fairly technical to non-nerds.

Representative Quote: "Science is not about what's true or what might be true, science is about what people with originally diverse viewpoints can be forced to believe by the weight of public evidence." -Lee Smolin

Viewing tip: the introductions are nice, and they explain each panelist's background (two are high school dropouts!), but they are eminently skippable. If you want to get right into the discussion, skip ahead to about 17:00.

Further Reading

Several of these panelists, and NDT himself, have written great books. I'd recommend Brian Greene's books The Fabric of the Cosmos and The Hidden Reality.


I haven't found a transcript of this discussion, and the auto-captions are awful. If you locate a good transcript, please point it out in the comments.

Suggest a Lecture

Got a favorite lecture? Is it online in some video format? Leave a comment and we'll check it out! Many thanks to reader James for suggesting this one.