**NIU math: Ben Wallis**

**Research interests:** My primary area of interest lies in Banach space theory, with a current focus in the study of almost-invariant halfspaces, Tsirelson-type spaces and their variants, and operator ideals.

**Publications:**

"Constructing Banach ideals using upper \ell_p-estimates," *Extracta Mathematicae*, Vol. 29, No. 1-2 (2014), pp73-95. (pdf)

"The structure of almost-invariant half-spaces for some operators" (with Gleb Sirotkin), *Journal of Functional Analysis*, Vol. 267, Iss. 7 (2014 Oct 01), pp2298-312.

**Submitted Publications:**

"Classes of operators determined by ordinal indices" (with Kevin Beanland, Ryan Causey, and Daniel Freeman). arXiv:1507.06285v1 [math.FA] (pdf)

"Closed ideals in \mathcal{L}(X) and \mathcal{L}(X^*) when X contains certain copies of \ell_p and c_0." arXiv:1507.03241v1 [math.FA] (pdf)

**Talks:**

2015 Jun 09, "Constructing Banach ideals using upper \ell_p-estimates," *Relations Between Banach Space Theory and Geometric Measure Theory*, University of Warwick, Coventry, UK. (youtube)

2015 Mar 03, "Constructing Banach ideals using upper \ell_p-estimates," seminar talk, Northern Illinois University, Dekalb, IL, USA.

2014 Oct 07, "The almost-invariant halfspace problem" (joint with
Gleb Sirotkin), seminar talk, Northern Illinois University, Dekalb, IL,
USA.

2014 Sep 27, "Constructing Banach ideals using upper \ell_p-estimates," *Wabash annual miniconference*, Indiana University-Purdue University Indianapolis, Indianapolis, IN, USA. (pdf)

2014 May 23, "Schreier-supported upper \ell_p-estimates on Banach space operators," *Seventh conference on function spaces*, Southern Illinois University---Edwardsville, Edwardsville, IL, USA. (pdf)

2014 Mar 07, "The almost-invariant halfspace problem" (joint with
Gleb Sirotkin), seminar talk, University of Alberta, Edmonton, AB,
Canada.

2013 Sep 28, "The almost-invariant halfspace problem" (joint with Gleb Sirotkin), *Wabash annual miniconference*, Indiana University-Purdue University Indianapolis, Indianapolis, IN, USA.

**Referee experience:**

Referee for *Positivity* (2014-present)

**Teaching experience:**
*At NIU:* MATH 101 (Topics in Math), 109p (Chance Program Fundamentals of Math II), 110p (Chance Program College Algebra), 155 (Trig/Precalculus), 201 (Foundations of Elementary School Math), 211 (Business Calculus), 229 (Calculus I), and 230 (Calculus II).
*At Kishwaukee College:* MAT 096 (Algebra I), 097 (Geometry), 098 (Algebra II), 150 (College Algebra), and 220 (Business Statistics).

For questions or comments, you can contact me via email: `z1019463@students.niu.edu`

Last updated: 2015 Jul 14