About

William Irvine is a Professor of Physics at the University of Chicago. His research focuses on various aspects of fluid dynamics and active matter, including chiral fluids, colloidal systems, turbulence, vortex dynamics, and self-assembly. His work involves exploring complex behaviors in physical systems, often utilizing experimental and theoretical approaches to understand phenomena such as vortex nucleation, vortex knots, and intermediate Reynolds flow. Throughout his career, Professor Irvine has contributed to the understanding of dynamical systems and fluid mechanics, with a particular interest in vortex behavior and turbulence. His research group investigates the fundamental principles governing these systems, aiming to uncover new insights into their underlying physics. His lab also explores the intersection of active matter and active fluids, contributing to the broader understanding of non-equilibrium systems in soft condensed matter physics.

Research topics

• Classical mechanics
• Physics
• Mechanics
• Quantum mechanics
• Thermodynamics
• Mathematical physics
• Particle physics
• Optics
• Mathematical analysis
• Mathematics

Selected publications

• Supporting data for Matsuzawa, Zhu, et al., "Nonlinear Diffusion and Decay of a Blob of Turbulence Spreading Into a Quiescent Fluid", PNAS, (2026)

  Zenodo (CERN European Organization for Nuclear Research) · 2026-01-26

  datasetOpen accessSenior author

  Paper: Nonlinear Diffusion and Decay of a Blob of Turbulence Spreading Into a Quiescent Fluid Authors: Takumi Matsuzawa, Minhui Zhu, Nigel Goldenfeld, William T. M. Irvine Description:This repository contains the data presented in Figures 1–5 of the paper, which examine the decay and propagation of turbulence generated by repeatedly colliding vortex rings. In the study, we also explored turbulence decay generated by oscillating a double grid. Each folder contains the data used to produce the main figures. For Figures 1C–F and 4C–F, we present time slices of ensemble-averaged fields, including energy and enstrophy. The original velocity field data is approximately 10 GB per sample. We performed 21, 10, and 10 replications for the blob, double oscillating grid, and single oscillating grid configurations, respectively. From these, Reynolds averaging was applied to extract the turbulent (fluctuating) components. Contents:Each folder contains HDF5 files with relevant data that made it into the plot. E.g. Figure 2B_tegral_lengthscale.h5 contains/blob/t_t0: t-t0/blob/ell: ell (Integral length scale) from the blob experiments/blob/ell_scaled: ell / Lbox (Scaled integral length scale)...

  PublisherDOI

• Nonlinear diffusion and decay of a blob of turbulence spreading into a quiescent fluid

  Proceedings of the National Academy of Sciences · 2026-02-12

  articleOpen accessSenior authorCorresponding

  Turbulence, left unforced, evolves under its own dynamics, invading surrounding quiescent fluid as it decays. A ubiquitous and familiar phenomenon, this fundamental aspect of turbulence has resisted the marriage of principled theory and experiment with no universal law yet capturing its evolution. Conventional flow chamber experiments have been hampered by boundary effects or strong mean flows that obscure the intrinsic dynamics of relaxation to quiescence. To circumvent these limitations, we create a spatially localized blob of turbulence using eight converging vortex generators focused at the center of a water tank, and observe its decay and expansion over decades in time using particle image velocimetry with logarithmic time sampling. The blob initially expands and decays until it reaches the walls of the tank and eventually transitions to a second regime of approximately spatially uniform decay. We interpret the turbulent dynamics as an interplay of nonlinear diffusion with associated steep fronts separating the turbulent and quiescent regions, and nonlinear decay, as described by the Kolmogorov-Barenblatt equation. We find direct evidence for this model within the expansion phase and decay phases of our turbulent blob and use it to account for the detailed behavior we observe. Our work provides a detailed spatially resolved narrative for the behavior of turbulence once the forcing is removed, and demonstrates unexpectedly that the turbulent cascade leaves an indelible footprint far into the decay process.

  PublisherDOI

• Supporting data for Matsuzawa, Zhu, et al., "Nonlinear Diffusion and Decay of a Blob of Turbulence Spreading Into a Quiescent Fluid", PNAS, (2026)

  Open MIND · 2026-01-26

  datasetSenior author

  Paper: Nonlinear Diffusion and Decay of a Blob of Turbulence Spreading Into a Quiescent Fluid Authors: Takumi Matsuzawa, Minhui Zhu, Nigel Goldenfeld, William T. M. Irvine Description:This repository contains the data presented in Figures 1–5 of the paper, which examine the decay and propagation of turbulence generated by repeatedly colliding vortex rings. In the study, we also explored turbulence decay generated by oscillating a double grid. Each folder contains the data used to produce the main figures. For Figures 1C–F and 4C–F, we present time slices of ensemble-averaged fields, including energy and enstrophy. The original velocity field data is approximately 10 GB per sample. We performed 21, 10, and 10 replications for the blob, double oscillating grid, and single oscillating grid configurations, respectively. From these, Reynolds averaging was applied to extract the turbulent (fluctuating) components. Contents:Each folder contains HDF5 files with relevant data that made it into the plot. E.g. Figure 2B_tegral_lengthscale.h5 contains/blob/t_t0: t-t0/blob/ell: ell (Integral length scale) from the blob experiments/blob/ell_scaled: ell / Lbox (Scaled integral length scale)...

  DOI

• Melting of nonreciprocal solids: How dislocations propel and fission in flowing crystals

  Proceedings of the National Academy of Sciences · 2025-04-11 · 3 citations

  articleOpen access

  When soft matter is driven out of equilibrium its constituents interact via effective interactions that escape Newton's action-reaction principle. Prominent examples include the hydrodynamic interactions between colloidal particles driven in viscous fluids, phoretic interactions between chemically active colloids, and quorum-sensing interactions in bacterial colonies. Despite a recent surge of interest in nonreciprocal physics, a fundamental question remains: do nonreciprocal interactions alter or strengthen the ordered phases of matter driven out of equilibrium? Here, through a combination of experiments and simulations, we show how nonreciprocal forces propel and fission dislocations formed in hydrodynamically driven Wigner crystals. We explain how dislocation motility results in the continuous reshaping of grain-boundary networks, and how their fission reaction melts driven crystals from their interfaces. Beyond the specifics of hydrodynamics, we argue theoretically that topological defects and nonreciprocal interactions should invariably conspire to deform and ultimately destroy crystals.

  PublisherDOI

• Nonlinear Diffusion and Decay of an Expanding Turbulent Blob

  ArXiv.org · 2025-05-28

  preprintOpen accessSenior author

  Turbulence, left unforced, decays and invades the surrounding quiescent fluid. Though ubiquitous, this simple phenomenon has proven hard to capture within a simple and general framework. Experiments in conventional turbulent flow chambers are inevitably complicated by proximity to boundaries and mean flow, obscuring the fundamental aspects of the relaxation to the quiescent fluid state. Here, we circumvent these issues by creating a spatially-localized blob of turbulent fluid using eight converging vortex generators focused towards the center of a tank of water, and observe its decay and spread over decades in time, using particle image velocimetry with a logarithmic sampling rate. The blob initially expands and decays until it reaches the walls of the tank and eventually transitions to a second regime of approximately spatially uniform decay. We interpret these dynamics within the framework of a nonlinear diffusion equation, which predicts that the ideal quiescent-turbulent fluid boundary is sharp and propagates non-diffusively, driven by turbulent eddies while decaying with characteristic scaling laws. We find direct evidence for this model within the expansion phase of our turbulent blob and use it to account for the detailed behavior we observe, in contrast to earlier studies. Our work provides a detailed spatially-resolved narrative for the behavior of turbulence once the forcing is removed, and demonstrates unexpectedly that the turbulent cascade leaves an indelible footprint far into the decay process.

  PublisherOA PDFDOI

• Self-propulsion, flocking and chiral active phases from particles spinning at intermediate Reynolds numbers

  Nature Physics · 2024-10-08 · 26 citations

  articleOpen accessSenior authorCorresponding
  PublisherOA PDFDOI

• Self-propulsion, interactions, and flocking of active vortlets in three dimensions

  HAL (Le Centre pour la Communication Scientifique Directe) · 2024-03-04

  articleSenior author

  Session S31: Steerable Particles: New Ways to Manipulate Fluid-Mediated Force.

  Publisher

• Creation of an isolated turbulent blob fed by vortex rings

  Nature Physics · 2023 · 34 citations

  Senior authorCorresponding
  • Physics
  • Mechanics
  • Classical mechanics
  PublisherOA PDFDOI

• Self-propulsion of rotating axisymmetric particles at intermediate Reynolds number

  HAL (Le Centre pour la Communication Scientifique Directe) · 2023-11-19

  articleSenior author

  International audience

  Publisher

• Turbulence through sustained vortex ring collisions

  Physical Review Fluids · 2023-11-16 · 1 citations

  articleOpen accessSenior author

  This paper is associated with a video winner of a 2022 American Physical Society's Division of Fluid Dynamics (DFD) Gallery of Fluid Motion Award for work presented at the DFD Gallery of Fluid Motion. The original video is available online at the Gallery of Fluid Motion, https://doi.org/10.1103/APS.DFD.2022.GFM.V0008

  PublisherOA PDFDOI

Recent grants

• Chiral Fluids

  NSF · $565k · 2019–2024

• CAREER: Topological Vortex Dynamics

  NSF · $650k · 2014–2020

Frequent coauthors

• Dustin Kleckner

  University of California, Merced

  38 shared

• Dirk Bouwmeester

  Leiden University

  34 shared

• Michael Shelley

  30 shared

• Vincenzo Vitelli

  University of Chicago

  26 shared

• Stefano Sacanna

  New York University

  24 shared

• Vishal Soni

  University of North Texas

  21 shared

• Noah Mitchell

  21 shared

• Martin W. Scheeler

  University of Chicago

  20 shared

Labs

• Irvine LabPI

  Not provided

Awards & honors

• UChicago Physicist William Irvine selected for $2 million Br…