I only wish to tell you that with your background, every single thing that's been discussed on this forum that you think is beyond you, is actually trivially within your capabilities and knowledge. — fishfry
Fair enough. When I speak of a topic being "beyond me" it's a cop-out for not having the mental energy at my age (83) to study it, or just a complete lack of interest. I appreciate your comment.
Every so often, however, something a bit out of my purview will intrigue me and I will make an effort to understand it. For example, a couple of years ago the notion of a
functional integral sparked my interest, having read of Feynman's Sum of All Paths concept. My brief exposure to the concept fifty years ago was shallow and uncompelling.
That was a delightful exploration, starting with the basic Wikipedia definition, and I wrote a short math note about functional integrals in spaces of complex contours. I enjoy writing math programs, especially graphics, and I came up with some nice imagery. That was fun.
I should not be making dismissive comments about set theory. You, fdrake, Nagase, and a few others have clearly explained ideas in this subject, and it is a powerful link between math and philosophy, and a vital part of the mathematical galaxy. I apologize, and if I slip up in the future you should nail me!
Most of my research efforts have been in classical analysis, very basic dynamical systems in the complex plane, trying to determine convergence/divergence of certain sequences. At one time this was a popular topic, but modern analysis has moved the focus more toward algebraic systems and generalizations.
But I remain attached to the old-fashioned, nuts and bolts, stuff. For example, my latest efforts concern the iteration of linear fractional transformations (f(z)=(az+b)/(cz+d)) when the attracting fixed points are functions of time and are no longer "fixed". Like predator and prey, do the iterates "catch up" with the roving attractors? Modern theory dealing with LFTs is more geometrical and algebraic.
OK. Enough rambling. Thank you for your comments.