William A. Cherry

Associate Professor of Mathematics

University of North Texas


Office Hours

Spring 2018

Office Location: General Academic Building (GAB) 405.
Office Hours:  Mondays 10-Noon
 Tuesdays 1-2
 Wednesdays 1-3
 Thursdays 3:30-4:30
 and by appointment

Contact Information

E-mail:  wcherry@unt.edu

Phone:  (940) 565-4303

Fax: (940) 565-4805
Mailing Address: Department of Mathematics
University of North Texas
1155 Union Circle #311430
Denton, TX  76203-5017
Delivery Address: Department of Mathematics
General Academic Building, Room 435
University of North Texas
225 S. Avenue B (Avenue B at Mulberry)
Denton, TX  76203


Spring '18 Courses

Math 2700 -- Linear Algebra & Vector Geometry
Class Meets MWF 8-8:50 in BLB 225.
Final Exam: Monday, May 7, 8-10 in BLB 225.
Math 4060 -- Foundations of Geometry
Class Meets MWF 9-9:50 in CURY 110.
Final Exam: Wednesday, May 9, 8-10 in CURY 110.
Math 5320 -- Functions of a Real Variable
Class Meets TR 2-3:20 in GAB 438.
Final Exam: Thursday, May 10, 1:30-3:30 in GAB 438.

Fall '17 Courses

Math 2730 -- Multivariable Calculus
Section 003 Meets TR 3:30-4:50 in CHIL 245.
Section 003 Final Exam: Tuesday, December 12, 1:30-3:30 in CHIL 245.
Section 004 Meets TR 5:00-6:20 in PHYS 104.
Section 004 Final Exam: Tuesday, December 12, 5-6:20 in PHYS 104.
Math 3740 -- Vector Calculus
Class Meets MW 2-3:20 in WH 216.
Final Exam: Monday, December 11, 1:30-3:30 in WH 216.
Math 6620 -- Algebraic Topology
Class Meets MWF 11-11:50 in GAB 461.
Final Exam: Monday, December 11, 10:30-12:30 in GAB 461.

Research Interests

I have done work that can be considered complex analysis, number theory, and algebraic geometry. I am especially interested in connections between rational solutions and functional solutions to systems of algebraic equations. For instance, consider the equation of the unit circle, x2+y2=1. This equation has many rational solutions, such as (3/5)2+(4/5)2=1, coming from Pythagorean triples. The unit circle equation also has the "functional solution" (sin t)2+(cos t)2=1. On the other hand, if n>3, then xn+yn=1 has only a few rational solutions (this is Fermat's Last Theorem/Wiles's Theorem or the Mordell Conjecture/Faltings's Theorem, depending on what one means by "few" and "rational"). Similarly, xn+yn=1 has no non-constant "entire function" solutions -- this follows easily from, for instance, the Uniformization theorem. One area I often work in is a field called "p-adic" analysis. Working with functions of p-adic numbers is sort of halfway in between algebra and analysis, so the idea is it might help us understand how functional solutions are related to rational solutions. Another area I work in is Nevanlinna theory, which extends the Fundamental Theorem of Algebra to meromorphic functions. Finally, I have research interests in classical complex analysis, particularly using geometric methods to better understand various inequalities.

Graduate Advising

If you are a UNT mathematics graduate student looking for an advisor and are considering asking me, here is some basic information.


  click here for a list of my publications or click here to find my preprints on the arXiv.
Click here to see my author profile in Mathematical Reviews.

Click here to see my citations according to Google Scholar.

Look me up in the Mathematics Genealogy Project.

Conferences and other programs I will be attending

 Joint International Meeting of the American Mathematical Society and the Chinese Mathematical Society, Fudan University, Shanghai, China, June 11-14, 2018
 Resonances of complex dynamics, International Center for Mathematical Sciences, Edinburgh, UK, July 9-13, 2018
 Joint International Meeting of the American Mathematical Society and the Vietnamese Mathematical Society, Quy Nhon, Vietnam, June 10-13, 2019

Other upcoming conferences/meetigs

  Nevanlinna theory and Complex Geometry in Honor of Le Van Thiem's Centenary, Institute of Mathematics, Hanoi, Feb 26 - Mar 2, 2018.
 XIXth Conference on Analytic Functions and Related Topics, Rzeszow, Poland, June 25-29, 2018
  Arithmetic and geometry of local and global fields, Tuan Chau, Vietnam, June 25 - July 1, 2018.
 p-Adic Analysis & Dynamical Systems, Poznan University of Technology, Poznan, Poland, July 9-13, 2018
 One Day Function Theory Meeting, London, UK, September 3, 2018
 Open Questions in Cryptography and Number Theory, UC Irvine, September 17-21, 2018
 Analytic Low-Dimensional Dynamics: a celebration of Misha Lyubich's 60th birthday, Fields Institute, Toronto, Canada, May 27 - June 7, 2019.


Educational/Professional History

  click here for a brief description of my educational and professional background

Maple Tutorial

Click here for a brief introduction to the computer algebra system Maple


Fun and Games

Click here to generate some "fractal" graphics associated with Newton's method.



Beautiful Numbers, by John R. Swallow [American Scholar 64 (1995)]: A delightful essay written by a graduate school colleague of mine about his transformation from a first-year graduate student to a successful mathematician and scholar. I recommend this essay to new graduate students struggling with deciding what to study, who to choose as an advisor, and finding one's personal mathematical aesthetic.
Ludic Proof: Greek Mathematics and the Alexandrian Aesthetic, by Reviel Netz [Cambridge, 2009]: A book I am looking forward to reading about the literary qualities of mathematics and commonalities between writing mathematics (which I mostly understand) and writing poetry (which I mostly don't understand, but admire nonetheless).

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