**Welcome to Professor Nathan S. Feldman's Webpage!
**Also see my W&L faculty profile page

**π**

**= 3.14159 26535 89793 23846 26433 83279 50288 41971 69399 37510…**

**Fall 2020 Teaching Schedule**

Monday | Tuesday | Wednesday | Thursday | Friday | |

8:30-9:30 |
Math 332-01 ODEs in CGL 126 |
Math 332-01 ODEs in CGL 126 |
Math 332-01 ODEs in CGL 126 |
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9:45-11:15 |
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11:30-12:30 |
Math 221-01 Calc 3 in CGL 126 |
Math 221-01 Calc 3 in CGL 126 |
Math 221-01 Calc 3 in CGL 126 |
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12:45 - 2:15 |
Office Hours | Office Hours | Office Hours | ||

2:30-3:30 |
Math 221-02 Calc 3 in CGL 126 |
Math 221-02 Calc 3 in CGL 126 |
Math 221-02 Calc 3 in CGL 126 |

Office hours also available by appointment

**Contact Info
**Office: Chavis 304

Office Phone: 540-458-8033

Department Fax: 540-458-8239

e-mail: feldmanN@wlu.edu

About the Mathematics Department

The Math Center & Opportunities for Students

Washington & Lee University

Lexington, VA 24450

Below are a few links to some cool math sites...

http://mypiday.com - find out where your birthday appears within the digits of Pi.

https://www.angio.net/pi/piquery.html - the Pi Search page - find up to a million digits of Pi

https://www.piday.org - the day to celebrate pi - with pi of of course!

https://www.memory-improvement-tips.com/free-math-games.html

https://www.coolmath4kids.com

The Mathematics Genealogy Project. - At this site you can find out who the PhD advisor was for Einstein or for Newton or for any PhD mathematician. My mathematical genealogy starts with me, Nathan Feldman, and then my PhD advisor was John B. Conway, and his Phd advisor was Heron S. Collins, and then it continues this way with Billy James Petis, Edward J. McShane,.., Oskar Bolza, C. Felix Klein, Lipschitz, Dirichlet, Poisson & Fourier, Lagrange & Laplace, Euler, Johann Bernoulli, ..., Leibnniz,...

**Getting to know Professor Feldman...
**

**Why do I teach math?**

I teach math because I have a passion for it and I want to share that with my students and help them to see both the beauty and applications math.

**Why should you study math?
**Everyone should study as much math as possible because math is much more than just a list of rules and equations, it is really about logic, critical thinking, and problem solving skills and these basic tools are important to have throughout life. Also, math is very helpful and even required in the physical sciences and even in some of the social sciences.

**What is my research about?
**My research lies within the areas of linear operator theory and complex analysis. I use real analysis and complex analysis techniques to study properties of linear operators acting on Hilbert spaces, Banach spaces, and locally convex spaces. These spaces are complete infinite dimensional vector spaces that have a norm or an inner-product (= a dot product) over the real or complex numbers. You can think of a linear operator as a finite or an infinite matrix of numbers (kind of like a finite or an infinite excel spreadsheet of numbers!). I am particularly interested in linear operators acting on function spaces, such as multiplication operators, derivative operators, integral operators, Toeplitz operators and so on.

Much of my research involves the study of the dynamics of linear operators, which is the study of the predictable and the unpredictable or chaotic behavior of orbits of operators. Two important topics in operator theory are invariant subspaces and cyclic linear operators. My recent research involves investigating the newly discovered convex versions of these classic topics. In particular, investigating closed invariant convex sets for matrices and linear operators and convex-cyclic linear operators. Convex-cyclic operators are operators for which there is a vector x such that the smallest invariant convex set containing the vector x is dense in the space. These ideas can be studied in both finite and infinite dimensions and in both real and complex Banach and Hilbert spaces. See my recent publications for more details.