3,245 reputation
830
bio website PaulTaylor.EU
location London & Birmingham, UK
age
visits member for 5 years, 3 months
seen 2 days ago

I am an independent researcher in the foundations of mathematics and computation, using the techniques of category theory and type theory. I wrote a book called Practical Foundations of Mathematics (CUP 1999). My main work now is Abstract Stone Duality, which seeks to axiomatise computable general topology directly, without any recourse to set theory. I am also the author of a TeX package for drawing categorical diagrams.


2d
reviewed Leave Open embdedding standard models of PA into nonstandard models
2d
reviewed Leave Open About structure of the set of perfect matchings of $K_{n,n}$
2d
reviewed Leave Open Variance under time-scaling of sample measurements
2d
reviewed Leave Open why the split extension of a quasicyclic $2$-group $C$ by the cyclic group is not finite by abelien
2d
reviewed Leave Open Lower boundedness of the Ricci curvature
2d
comment In set theory, is there a name for a function which maps the empty set to zero and all the others to one?
The question asks, quite clearly, for the name of this function. It is the existential quantifier. That the question appears trivial is entirely the result of the destructive influence of set theory and classical logic on mathematics.
2d
reviewed Reopen In set theory, is there a name for a function which maps the empty set to zero and all the others to one?
Mar
27
reviewed Reopen A “better” rational approximation of pi?
Mar
26
reviewed Looks OK How to (efficiently) find intersection of two polyhedral cones?
Mar
26
reviewed No Action Needed Are there any Algebraic Geometry Theorems that were proved using Combinatorics?
Mar
26
reviewed No Action Needed Schoenflies and symplectic topology
Mar
26
reviewed Looks OK Proving that (e^x+1)^(1/3) has no elementary antiderivative
Mar
26
reviewed Leave Open Arbitrary chains of prime ideals in $R[X]$
Mar
26
reviewed Leave Open Differentiability and the Maximum Theorem
Mar
26
reviewed Reopen Differences between primitive central idempotents and primitive orthogonal idempotents
Mar
25
reviewed Leave Open Two surfaces with zero gaussian curvature
Mar
25
reviewed No Action Needed Flatness over a perfectoid ring
Mar
25
reviewed Leave Open Averages of bounded function
Mar
25
reviewed Reopen Consequences of technically proving anything in Coq (on at least Linux) exploiting a bug?
Mar
25
reviewed Leave Open What is wrong with the argument that zero permanent is polynomial?