This is the personal blog of me, Greg Langmead. I am a machine learning engineer at Apple, where I work on Apple News and Stocks.

I am also a student in the Philosophy department at Carnegie Mellon University. I study homotopy type theory and differential geometry. I use theorem proving software such as Agda and Lean.

I have a Ph.D. in mathematics from Columbia University (2001) where I studied gauge theory, supersymmetry, and four-dimensional topology. My dissertation was titled “A Supersymmetric Gauge Theory Formulation of the Donaldson Polynomial Invariants.”

Previously I worked at Design Science and SDL Language Weaver. I’m all over the map.

I’m interested in music and try to find time to practice piano, guitar and sometimes the ukulele. I love learning about the chord progressions used in music and am a frequent visitor to Theorytab.

My interests include mathematics, physics, software, board games (including their iPad versions), and I pile up video games for iOS, Xbox, PC and Mac and never quite get around to playing them. I do the same with books and movies.