Brown CS News

Tim Nelson, Daniel Ritchie, And James Tompkin Receive Promotions

    Click the links that follow for more news about Tim Nelson, Daniel Ritchie, James Tompkin, and other recent accomplishments by our faculty.

    Brown CS is happy to announce that faculty members Tim Nelson, Daniel Ritchie, and James Tompkin have received promotions. Pending the approval of Brown’s Corporation and effective as of July 1, 2024, Tim has been promoted to Senior Lecturer, Daniel to Associate Professor with tenure, and James to Associate Professor with tenure.

    Tim Nelson

    Tim came to Brown CS for postdoctoral work in 2013 after earning his Associate's degree from Diablo Valley College, Bachelor's degree from Worcester State University and PhD from Worcester Polytechnic Institute. He joined the faculty in 2018 as Assistant Professor (Research) and is the only person in his immediate family with a college degree: “Brown has many undocumented, first-generation, and low-income students, and it’s important they know I empathize with at least part of that experience.”

    One of the major factors that brought Tim to Brown was a keynote by Thomas J. Watson, Jr. University Professor of Technology and Education and Professor of Computer Science Andy van Dam, now almost twenty years past. “At the time,” Tim remembers, “I was deciding whether to go back to industry or on to grad school. It’s easy to think of faculty at places like Brown as entirely focused on research and not deeply caring about teaching, and here’s Andy who took the time to travel to New York and give this keynote focused on pedagogy. Teaching was so clearly important to him, and I’ve tried to live up to that inspiration.” 

    “The thing that set Tim apart,” says his former UTA and co-author Julianne Rudner, “was his commitment to not only creating technically capable engineers but also fostering an inclusive and accessible environment for all. He genuinely cares about his students as people and wants every person who takes one of his classes to get the most out of it, regardless of their background. In the tech industry, many people can possess the same knowledge or skillset, but what distinguishes a good engineer from a great one is the ability to be approachable, open-minded, and ask questions. Tim is an excellent model of this, and I’m proud to consider him a mentor.”

    Part of the PLT Group, Tim’s research interests include lightweight formal methods and formal-methods education. Among other courses, he runs CSCI 1710 Logic for Systems, a class that teaches lightweight formal methods by focusing on applications and tools. One example is Forge, a lightweight formal methods tool that’s built with teaching in mind.“I love doing research work with students,” Tim says, “and Forge has been a five-year project with many student collaborators. There are great tools out there, but most aren’t built for teaching.  Forge lets us do pedagogy research, not just curriculum. I’m proud of what we’ve built together.” A paper on the design of Forge will appear at this year’s OOPSLA conference.

    Daniel Ritchie

    Daniel Ritchie joined Brown CS as Assistant Professor in 2017 after completing an undergraduate degree at University of California, Berkeley and then a Master’s and PhD at Stanford University. He was appointed the Eliot Horowitz Assistant Professor of Computer Science in 2021.

    Daniel co-leads the Brown Visual Computing group and his research sits at the intersection of computer graphics, artificial intelligence, and machine learning – especially how AI and ML tools can make the process of creating graphics content easier, more accessible, and more enjoyable. He’s interested in technologies for creating, manipulating, and analyzing 3D shapes and scenes, particularly neurosymbolic methods for doing so (combining the best aspects of procedural models and deep neural networks). His teaching includes CSCI 1230 Introduction to Computer Graphics and CSCI 2240 Advanced Computer Graphics.

    Daniel received an NSF CAREER Award in 2020 to develop 3D generative models that satisfy the criteria of quality, variety, efficiency, interpretability, economy, and universality, enabling scalable synthesis of high-quality objects for the expanding set of applications that demand them. He’s also led a NSF summer REU site, Artificial Intelligence for Computational Creativity, for the past two years. Daniel’s recent publications include “PossibleImpossibles: Exploratory Procedural Design of Impossible Structures”, “CharacterMixer: Rig-Aware Interpolation of 3D Characters”, and “Generalizing Single-View 3D Shape Retrieval to Occlusions and Unseen Objects”, and he gave talks on learning to represent shapes with programs at the Symposium on Geometry Processing Summer School and neurosymbolic generative models for structured 3D content at 3D Geometry and Vision (3DGV) Seminar. Most recently, Daniel’s service to the field has included serving as Program Committee Member / Area Chair for SIGGRAPH North America and SIGGRAPH Asia, NeurIPS, Eurographics, and other conferences. He’s also served as Associate Editor for Computer Graphics Forum and IEEE TVCG.

    Brown CS undergraduate Anh Truong is one of Daniel’s advisees. “Daniel has been a hugely inspiring and supportive mentor to me,” he says. “I continue to be surprised by how open and welcoming my research experience with him has been. He’s helped me navigate the joys and challenges of research, providing invaluable guidance along the way. I also admire Daniel's eagerness to welcome new folks into visual computing, especially those who would otherwise have limited opportunities. I believe his excitement about his work and dedication to mentoring students speak to his passion as both a researcher and educator. I'm very fortunate to have crossed paths with Daniel in my time here, and I have no doubt he will continue to inspire many future generations of students.”

    James Tompkin

    James joined Brown CS as Assistant Professor in 2016 after completing a PhD on large-scale video processing and exploration techniques at University College London and postdoctoral work at Max-Planck-Institute for Informatics and Harvard University. He was appointed the John E. Savage Assistant Professor of Computer Science in 2022.

    James co-leads the Brown Visual Computing group. His research in visual computing is at the intersection of computer vision, computer graphics, and human-computer interaction, where he helps to develop techniques for camera-captured media that remove barriers from image and video creation, editing, and interaction. Recently, he’s developed new image and scene reconstruction techniques, especially from multi-camera systems, including low-level depth reconstruction and view synthesis for VR. His teaching includes CSCI 1430 Computer Vision, CSCI 1290 Computational Photography, and CSCI 2000 Research Methods (or How to be a CS PhD Student).

    James received an NSF CAREER award in 2022 to investigate scene reconstruction from heterogeneous camera systems. His recent publications include “Semantic Attention Flow Fields” and “Are Multi-view Edges Incomplete for Depth Estimation?”, with collaborations that cover active illumination camera systems (“Neural Fields for Structured Lighting”) and large-scale reconstruction (“ScaNeRF: Scalable Bundle-Adjusting Neural Radiance Fields for Large-Scale Scene Rendering”). In his academic communities, he organizes a workshop at CVPR on AI for Content Creation (, and has taught tutorials and courses on neural fields ( and on video for VR at SIGGRAPH and CVPR. James served as Posters chair for SIGGRAPH North America in 2023, has served as Program Committee Member / Area Chair for SIGGRAPH North America and SIGGRAPH Asia, ECCV, Eurographics, and other conferences, and is an Associate Editor for Computer Graphics Forum.

    “James has been an inspiring mentor, always supportive of my growth and curiosity as a student and researcher,” says Master’s student Marc Mapeke, a member of Tompkin’s research group. “Over the past four years, his guidance has not only shaped my academic and research interests but has also inspired me to mirror his commitment to teaching and mentorship in my own career. His ability to support curiosity in his students through detailed discussions and advice has been key to my development. It's been a privilege to collaborate with and learn from James.”

    For more information, click the link that follows to contact Brown CS Communications Manager Jesse C. Polhemus.