Hello.

I am Chengyuan Deng, a DSAI postdoc fellow at Johns Hopkins University. Before this, I had a few wonderful PhD years at Rutgers Theory Group, where I was fortunate to be advised by Jie Gao. I was a quantitative research intern at Polymer Capital Management. I was a research intern at Amazon, NEC Labs and Los Alamos National Lab.

My research revolves around algorithm design, geometry and trustworthy AI.

I am broadly interested in Theoretical Computer Science and Machine Learning. My experience with the first is in algorithm design for graph and geometry problems, while the second points to building the theoretical foundations of practical learning problems and devising algorithms with rigorous guarantees such as privacy and fairness. I am particularly drawn to problems that have a neat formulation and are of intrinsic theoretical interest, yet also surprisingly connect to applications in practice.

Beyond the above, I am working on LLMs and mathematical aspects of music, such as combinatorics and geometry.

I am training myself as a researcher and classical musician slowly.

Contact:

Publications

As is the convention in Theoretical Computer Science, authors are listed in alphabetical order. Empirical ML papers are exceptions in this list.

Recognitions

Invited Talks

  • Euclidean Ideas Beyond Euclidean Geometry, Theory Seminar at Johns Hopkins University, 2026
  • Locality Sensitive Hashing in Hyperbolic Space, Rutgers DIMACS Theory Seminar, 2026
  • Property Testing for Correlation Clustering, NYC Graduate Student Theory Day, 2026
  • Dimension Reduction Beyond Euclidean Geometry, Research Group Theory and Applications of Algorithms, University of Vienna, 2025
  • Dimension Reduction Beyond Euclidean Geometry, Big Data Algorithm Group, University of Salzburg, 2025
  • Dimension Reduction Beyond Euclidean Geometry, Halıcıoğlu Data Science Institute, University of California, San Diego, 2025
  • Johnson-Lindenstrauss Lemma Beyond Euclidean Geometry, Fall Workshop on Computational Geometry, 2025
  • Low Sensitivity Hopsets, NYC Graduate Student Theory Day, 2024
  • The Discrepancy of Shortest Paths, Rutgers DIMACS Theory Seminar, 2024
  • Explainable Clustering, Harvard Theory Reading Group of Physics ML, 2023

Professional Service

  • Reviewer, SOSA 2026; SoCG 2026; RANDOM 2025; NeurIPS 2023–25; ICLR 2023–25
  • Guest Lecturer and Advising, Machine Learning course at Quisqueya University, Haiti

Honors and Awards

  • Rizvi Research Excellence Award, 2025
  • Rutgers SGS Travel Award, 2025
  • Travel Award, WADS 2023
  • Travel Award, NeurIPS 2022
  • Master's degree with honors, Outstanding Publication Award
  • Yamaha Asian Music Scholarship, 3rd Place

Music

I am gradually constructing this site to include performance recordings, compositions, analysis and notes.

We are organizing regular meetups in New York City to perform solo, chamber and orchestral music. Drop me a line if you are interested!

Music Experience

I play the piano, both solo and chamber. I am learning to play the cello. Musicianship is my first priority, and I am teaching myself conducting and composition.

  • Muffin Music Piano Intensive — Santa Ynez Valley, California (July 2025)

    It was such a pleasure to study with Ms. Sylvia Jiang and Ms. Yoon Hi Moon! The experience became the first thing I missed about the summer of 2025.

  • Alaria Chamber Music — New York (June 2025)

    We played the third movement of Arensky's Piano Trio, a piece I was not fond of at first but later found so lovely.

  • Juilliard School Chamber Music — New York (2024)

    We played two of my favorite chamber pieces; recordings are available below.

  • Rutgers Glee Club — New Brunswick, NJ (2022-2023)

    We performed Beethoven and Brahms at Carnegie Hall, one of my loveliest memories.

Chamber music recordings

I have recently found much pleasure in chamber music. I do not find it a contradiction to a soloist's strong personality, but rather a different way of expressing it—one that thrives on dialogue, sensitivity, and the subtle interplay between voices. Below are performance recordings of some of my favorite chamber music pieces with musician friends.

Beethoven: Piano Trio in B-flat Major, Op. 97 "Archduke" - Mov I. Allegro moderato

Violin: Seeun Baek, Cello: Jiaxun Yao, Piano: Chengyuan Deng

Date: April, 2024 | Juilliard School, New York

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This is one of the rare occasions in Beethoven’s oeuvre where his music achieves a fully realized sense of peacefulness and pastoral gentleness. The Archduke Piano Trio, composed in 1811–12, is not only a masterpiece of his mature chamber style but also a testament to his relationship with Archduke Rudolf of Austria, his student, friend, and generous patron. The first movement opens with a broad, noble piano theme that seamlessly engages in a refined dialogue with violin and cello, blending virtuosic brilliance with intimate expressiveness.

Dvořák: Piano Quintet in A Major, Op. 81 - Mov I, II, & III

Violin: Julie Minn, Yubin Kim, Viola: Adam Savage, Cello: Edison Liu, Piano: Chengyuan Deng

Date: Dec, 2024 | Juilliard School, New York

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This piece, in my opinion, among a few others, is chamber music perfection. It brims with folk-inspired character, drawing on the rhythms, modes, and melodic contours of Bohemian dance and song. These elements are woven seamlessly into the fabric of the work, giving the piano and strings a natural, conversational energy that feels both spontaneous and deeply expressive. One thing I would do at the end of the 4th movement is to imagine: does this feel like a sunset with reflections, or is another dance party about to begin?

Brahms: Piano Quintet in F minor, Op. 34 - Mov IV

Violin: Julie Minn, Erin Nishi, Viola: Wesley O'Brien, Cello: Christy Choi, Piano: Chengyuan Deng

Date: May, 2026 | Juilliard School, New York

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I love this finale for its sheer, kaleidoscopic cast of personalities. After three movements of massive, muscular tension, the finale actually starts off creeping around in the dark with a moody, unsettling introduction. This suspense quickly breaks, launching directly into the driving, syncopated rhythm of a Hungarian folk dance. The scenes keep changing, but the Brahmsy gravity is always there. The coda is phenomenal. It takes off in a wild, breathless sprint, gathering all that restless energy and pulling it firmly back into the dark home key of F minor for a fierce, uncompromising finish.

I learnt this movement during my final semester; playing it feels like a mirror of my PhD journey. Keep dancing!