About Me
Hi! I’m a 3rd-year Algorithms, Combinatorics, and Optimization (ACO) PhD Student at Carnegie Mellon University (CMU) in the Operations Research department. My research interests are broadly in approximation algorithms and combinatorial optimization, where I have primarily worked with Benjamin Moseley.
Before joining CMU, I obtained my B.S. in Computer Science and Mathematics from the University of Pittsburgh, where I was mentored by Kirk Pruhs.
Contact Info: sarndt@andrew.cmu.edu
Publications
Conference Publications
Approximation Algorithms for Matroid-Intersection Coloring with Applications to Rota's Basis Conjecture
Stephen Arndt, Benjamin Moseley, Kirk Pruhs, Chaitanya Swamy, and Michael Zlatin. FOCS 2026.
Efficiently Coloring the Intersection of a General Matroid and Combinatorial Matroids
Stephen Arndt, Benjamin Moseley, Kirk Pruhs, and Michael Zlatin. IPCO 2026.
Competitive Online Transportation Simplified
Stephen Arndt, Benjamin Moseley, Kirk Pruhs, and Marc Uetz. SOSA 2026.
An O(log n)-Competitive Posted-Price Algorithm for Online Matching on the Line
Stephen Arndt, Josh Ascher, and Kirk Pruhs. COCOA 2023.
Resource Augmentation Analysis of the Greedy Algorithm for the Online Transportation Problem
Stephen Arndt, Josh Ascher, and Kirk Pruhs. LAGOS 2023.
arXiv Preprints
Matroid Contention Resolution with Concentration
Stephen Arndt, Benjamin Moseley, Kirk Pruhs, and Michael Zlatin. arXiv preprint.
No, Cake Cutting Really is a Piece of Cake
Stephen Arndt, Benjamin Moseley, Sungjin Im, and Kirk Pruhs. arXiv preprint.
An Ω(n log n) Randomized Lower Bound for Cutting a Cake into Proportionally Fair Pieces
Stephen Arndt, Kirk Pruhs, and Trung Tran. arXiv preprint.
Invited Talks
Approximation Algorithms for Matroid-Intersection Coloring with Applications to Rota’s Basis Conjecture
- Jul 2027: ISMP 2027 Approximation and Online Algorithms session talk
- Sep 2026: UIUC CS Theory Seminar
- Sep 2026: Michigan CS Theory Seminar
- May 2026: Waterloo Graphs and Matroids Seminar
- Apr 2026: CMU OR Seminar
Teaching
TAing
- Summer (Mini) 2026: Optimization for Business (undergrad)
- Spring 2026: Optimization for Business (undergrad)
- Spring 2026: Integer Programming (graduate)
Grading
- Spring 2026: Final Grader, Optimization for Business (MBA)
Professional Activities
CMU INFORMS
Roles
- Aug 2024–25: Undergrad Outreach Chair
- Mar–Aug 2025: YinzOR Flash Talk & Poster Session Co-Chair
- Aug 2025–26: Treasurer
- Mar–Aug 2026: YinzOR Logistics Co-Chair
- Aug 2026–27: President
Talks
- Feb 2024: Pitt CSC Grad School Talk
- Nov 2024: CMU OR Grad School Talk
- Feb 2025: Pitt CSC Grad School Talk
Meet-and-Think Seminar
Meet-and-Think Seminar is an informal, student-only weekly seminar for CMU OR, ACO, Math, etc. PhD Students whose primary purposes are to a) learn about other students’ research topics or interests, b) give a casual environment for students to meet and practice speaking skills, and c) to receive a free afternoon snack each week 😃.
Organizer: Mar 2025–Present
Reviews
Current review counter: 7
- 2026: FOCS, APPROX, IEEE ToN, ORL
- 2027: SODA (x3)
Awards and Scholarships
- Mar 2026: Litzenberger Family Fund
- Jan 2026: Egon Balas Award (Best CMU OR/ACO Summer Paper)
- Aug 2024: Dean’s PhD Scholarship Award
- Apr 2024: Pitt CS Outstanding Undergraduate Award