# Steven Leth, Ph.D.

# Professor

**Contact Information**

**Phone:**(970) 351-2457**Email:**steven.leth@unco.edu**Office:**Ross Hall 2240-B

## Education

- Ph.D., Mathematics, University of Colorado (1985)
- M.S., Mathematics, Stanford University (1978)
- B.S., Mathematics and Physics, University of Colorado (1976)

## Current Research and Publications

My research is in the area of nonstandard analysis, which could be described as a method for applying concepts from logic to other branches of mathematics. I have published several papers in which this method is used to obtain results in such areas as combinatorial number theory and geometric topology. I am also interested in methods of teaching mathematics, and have given a number of talks about calculus reform, writing in mathematics classes and ways to enrich the mathematical curriculum at the elementary and middle school levels. I would be happy to share reprints of papers or discuss any of these issues, mathematical or educational with anyone who is interested.

#### Three most recent research papers:

- Nonstandard
methods and the Erdos-Turan conjecture, in
*The Strength of Nonstandard Analysis*, van den Berg and Neves (eds.), Springer - Near Arithmetic Progressions in Sparse Sets, Proceedings of the American Mathematical Society (134) no. 6, June 2006, pp. 1579-1589
- Regions in the nonstandard plane that contain no standard set, Journal of Logic & Analysis 4:16 (2012) 1–17

Slides for recent research talks:

Chico Topology Conference, Chico, CA May 2012

Spring Topology Conference, Tyler, TX March 2011

AMS Sectional meeting on nonstandard analysis, Honolulu, HI, March 2012

Chico Topology Conference, Chico, CA, May 2010

Logic and Mathematics Conference, York, England, August 2009