>PRESENTATION:
Jeffrey Bub is a philosopher of physics with a special interest in the conceptual foundations ofquantum theory. He is the author of two books: The Interpretation of Quantum Mechanics (Reidel, 1974) and Interpreting the Quantum World (Cambridge University Press, 1997; revised paperback edition, 1999), which won the prestigious Lakatos Award in 1998. His current research is focused on quantum information and computation.

I present a new way of looking at the information-processing involved in a quantum computation, in terms of the difference between the Boolean logic underlying a classical computation and the non-Boolean logic represented by the projective geometry of Hilbert space, in which the subspace structure of Hilbert space replaces the set-theoretic structure of classical logic. The original Deutsch XOR algorithm, Simon's algorithm, and Shor's algorithm all turn out to involve a similar geometric formulation.