Peter Freyd is a category theorist, known for work in many areas of category theory, including adjoint functors, abelian categories, allegories, homotopy theory, polymorphism and topos theory.
On the relation between toposes and abelian categories and introducing the unifying notion of AT-categories:
On category theory:
Peter Freyd, The theories of functors and models, in: Proceedings of Symposium on the Theory of Models, North Holland, 1965 (doi:10.1016/C2013-0-11897-1)
Peter Freyd, Andre Scedrov, Categories, Allegories, Mathematical Library Vol 39, North-Holland (1990) (ISBN 978-0-444-70368-2)
On continuous functors (and introducing the notion of orthogonal factorization systems):
On bireflective subcategories with ambidextrous adjoints:
Peter Freyd has written several papers since 2008, but no longer submits his work for publication.
Some supplemental material for Categories, Allegories:
A significantly expanded version of the published TAC paper Algebraic Real Analysis:
A study of the relationship between the lambda calculus and combinatory logic:
Corrections for Categories, Allegories:
A proof of the fact that “In any field, any sum of four cubes is a sum of just three cubes.”:
An elementary proof of the RDP theorem:
A characterisation of and without limits:
An algebra puzzle:
An elementary proof of the fact that “Any finite-dimensional associative real algebra D without zero divisors is isomorphic either to a single point, the reals, the complex numbers or the quaternions.”:
An updated version of the TAC reprint:
A follow up to the paper On the concreteness of certain categories:
A fact about prime powers and permutations:
Last revised on October 6, 2024 at 14:03:09. See the history of this page for a list of all contributions to it.