About Me
I’m a senior undergraduate student (from 2023 Fall) at the Institute for Interdisciplinary Information Sciences (IIIS, Yao Class), Tsinghua University.
In Spring 2026, I was a visiting student at Carnegie Mellon University, where I was fortunate to be advised by Prof. Ryan O’Donnell, working on high-dimensional expanders (HDXs) and their applications to probabilistically checkable proofs (PCPs). Prior to this, I had the great pleasure of working with Prof. Huacheng Yu on streaming lower bounds. I have also greatly enjoyed collaborating with Prof. Zhengfeng Ji and Prof. Jian Li at Tsinghua University.
I am broadly interested in theoretical computer science and discrete mathematics. What fascinates me most is the rich interplay between the two, and I am actively exploring problems at their interface. My current research interests include:
- Streaming lower bounds and communication complexity
- Spectral and extremal graph theory
- Pseudorandomness and additive combinatorics
- High-dimensional expanders and the algebraic structures behind them.
News
- 2026.07: Our paper on turnstile streaming vs. linear sketching is accepted to FOCS 2026!
- 2026.05: Our paper on the lattice isomorphism problem is accepted to CRYPTO 2026!
- 2026.04: Our paper on the circuit width problem is accepted to TQC 2026!
- 2026.02: Started a research internship at Carnegie Mellon University, advised by Prof. Ryan O’Donnell.
- 2025.07: Our paper on adaptivity gaps for stochastic probing is accepted to FOCS 2025!
Publications
In theoretical computer science, authors are conventionally listed in alphabetical order.
-
Turnstile Streaming Algorithms Might (Still) as Well Be Linear Sketches, for Polynomial-Length Streams
Cheng Jiang, Yinchen Liu, Huacheng Yu
To appear in the IEEE Symposium on Foundations of Computer Science (FOCS), 2026.
[arXiv] [video] -
On the Complexity of the Circuit Width Problem
Zhengfeng Ji, Yinchen Liu, Zhe’ou Zhou
To appear in TQC 2026.
[arXiv] -
Exploiting the Complexity of Lattice Isomorphism Problem via Irreducible Decomposition
Kaijie Jiang, Yinchen Liu
To appear in the International Cryptology Conference (CRYPTO), 2026.
[eprint] -
Adaptivity Gaps for Stochastic Probing with Subadditive Functions
Jian Li, Yinchen Liu, Yiran Zhang
In the IEEE Symposium on Foundations of Computer Science (FOCS), 2025.
[arXiv] [video] -
On the Positive and Negative $p$-Energies of Graphs under Edge Addition
Quanyu Tang, Yinchen Liu, Wei Wang
In Discrete Applied Mathematics, vol. 388, pp. 25–33, 2026.
[journal] [arXiv]
Honors and Awards
- Yao Award (Silver), awarded to 3 students in Yao Class 2026
- Merit Student, Tsinghua University 2026
- National Scholarship, the highest honor for undergraduates in China, top 0.5% 2024 & 2025
- Academic Excellence Scholarship, Tsinghua University 2024 & 2025
- Freshman Scholarship, Tsinghua University 2023
- Merit Award, S.-T. Yau College Student Mathematics Contest (Algebra and Number Theory) 2023
- Merit Award, S.-T. Yau College Student Mathematics Contest (Probability and Statistics) 2023
- Merit Award, Alibaba Global Mathematics Competition 2022
- China Team Selection Test (TST) for IMO, rank 9 2021
- Gold Medal, Chinese Mathematical Olympiad (CMO), rank 16 2021
- Gold Medal, Chinese Mathematical Olympiad (CMO), rank 6 2020
Education
- B.Eng., Institute for Interdisciplinary Information Sciences (IIIS, Yao Class)
- Overall GPA: 4.00/4.00, Rank: 1/91
- TOEFL: 115/120
- Mathematics class
- Diamond Award (×2), top 10/400 each year
Services
- Reviewer for The Electronic Journal of Combinatorics (EJC) 2026
- Reviewer for International Cryptology Conference (CRYPTO), 2025 2025