# Ray Rosentrater

**Professor of Mathematics **

Phone: (805) 565-6185

Email: rosentr@westmont.edu

Office Location: Winter Hall 302

**Office Hours**

By appointment

**Specialization**

Operator theory

Professor Rosentrater has taught at Westmont since 1980, and has won the Teacher of the Year Award and the Faculty Research Award. He held a Fulbright fellowship in 1995. He commutes about 10 miles one way by bicylcle almost daily to work.

### Professor Rosentrater teaches

- Calculus
- Linear algebra
- Discrete mathematics
- Fundamentals of mathematics

### Education

- Ph.D. in Mathematics, Indiana University
- M.Sc. in Computer Science, University of Toronto
- M.S. in Mathematics, Indiana University
- B.A. in Mathematics, Messiah College

### Research Interests

- Operator theory

### Selected Publications

- "Representational Efficiency." Mathematics Magazine, 64 (2011), 185-195.
- (with Jim Gleason) “Xia’s Analytic Model of a subnormal Operator and its Applications.” Rocky

Mountain Journal of Mathematics. 38:3 (2008), 849-890. - (with Jim Gleason) “The Mosaic and Principal Function of a Subnormal Operator.” Integral Equations

and Operator Theory, 55 (2006), 69-82. - “Another Stick-Breaking Game: Problem 11089.” The American Mathematical Monthly, 113 (2006),

571-572. - “The Sample Correlation Coefficient from a Linear Algebra Perspective.” The College Mathematics

Journal, 36 (2006), 47-50.