In string theory, D-branes are a class of extended objects upon which open strings can end with Dirichlet boundary conditions, after which they are named, D-branes were discovered by Dai, Leigh and which American theoretical physicist, and string theorist?
Joseph Polchinski
Title: Joseph Polchinski
Passage: Joseph Polchinski (born May 16, 1954) is an American theoretical physicist and string theorist.
Title: D-brane
Passage: In string theory, D-branes are a class of extended objects upon which open strings can end with Dirichlet boundary conditions, after which they are named.  D-branes were discovered by Dai, Leigh and Polchinski, and independently by Hořava in 1989.  In 1995, Polchinski identified D-branes with black p-brane solutions of supergravity, a discovery that triggered the Second Superstring Revolution and led to both holographic and M-theory dualities.
Title: The Trouble with Physics
Passage: The Trouble with Physics: The Rise of String Theory, the Fall of a Science, and What Comes Next is a 2006 book by the theoretical physicist Lee Smolin about the problems with string theory.  Subtitled "The Rise of String Theory, the Fall of a Science, and What Comes Next", the book strongly criticizes string theory and its prominence in contemporary theoretical physics, on the grounds that string theory has yet to come up with a single prediction that can be verified using any technology that is likely to be feasible within our lifetimes.  Smolin also focuses on the difficulties faced by research in quantum gravity, and by current efforts to come up with a theory explaining all four fundamental interactions.  The book is broadly concerned with the role of controversy and diversity of approaches in scientific processes and ethics.
D-brane Joseph Polchinski