Joe Halpern's Home Page

JOSEPH Y. HALPERN

Professor

Cornell University
Computer Science Department
4144 Upson Hall
Ithaca, NY 14853
Tel: (607) 255-9562; Fax: (607) 255-4428
halpern at cs dot cornell dot edu

My research focuses on reasoning about knowledge and uncertainty, and its applications to distributed computing, AI, security, and game theory, although I've also done work (and continue to be interested in) such topics as fault tolerance in distributed computing, modal logic, program verification, and programming language semantics. My work lies at the boundary of a number of fields. I recently gave a talk in the economics department at Princeton where I described myself as someone with a Ph.D. in mathematics, who calls himself a computer scientist, and is giving a talk to economists about a subject mainly studied by philosophers. That's probably the best one-sentence description I can give. If you'd like more details, check my

list of publications.

It has pointers to abstracts of all my papers; in many cases, the paper itself is also available. Other details of my activities are in my

resume.

My work is supported by NSF, AFOSR, and ONR. I am also involved in a MURI project called SPYCE on Software Quality and Infrastructure Protection for Diffuse Computing and another called TIME-DC on Trustworthy Infrastructure, Mechanisms, and Experimentation for Diffuse Computing.

In the fall, I typically alternate between teaching

Reasoning About Knowledge (COM S 676).
Reasoning About Uncertainty (COM S 677).
Decision-Making in Complex Environments (COM S 576, crosslisted as CIS 577, ECON 476, and ECON 676) with Professors David Easley and Larry Blume in Economics.

I taught COM S 676 in Fall 2003, COM S 677 in Fall 2000, and COM S 576 in Fall, 2002.

In the spring, I usually teach an undergraduate course. I have taught COM S 280, COM S 409, COM S 410 in previous years. There's a good chance I'll be teaching one of them again.