Existence theorems constitute a fundamental pillar in the study of game theory and exchange economies. These theorems rigorously establish the conditions under which equilibria or stable outcomes ...

SIAM Journal on Numerical Analysis, Vol. 43, No. 3 (2006), pp. 1348-1361 (14 pages) We show how interval arithmetic can be used in connection with Borsuk's theorem to computationally prove the ...

As I work proofs with my Calculus and Higher Geometries students, I often run across the Greek symbol that, in math, means “there exists." This might show up, for example, in statements such as “there ...