Hi, I'm Guru.
I'm a fourth-year Physics PhD student at UC San Diego, advised by Nigel Goldenfeld. I work on the statistical mechanics of non-equilibrium systems, in problems spanning turbulence, ecology, and machine learning.
I'm mostly interested in how non-equilibrium systems transition into rich emergent states. A few questions drive my work:
- How do non-equilibrium systems move between states, and what governs the transition? I study this in transitional flows: the onset of turbulence in pipe flow, Taylor–Couette flow, and related systems. I'm interested in how new states emerge as a reorganization of length, energy, and time scales, and how the interplay between these scales controls the spatiotemporal organization and dynamics as the system passes from one state to another. In pipes with body forces, for example, I showed that the transition is governed by tricritical directed percolation (Physical Review Letters, 2025).
- Can such core principles be generalized and utilized to seek simpler modeling priors in complex yet realistic settings? The goal is to find simple descriptions of phenomena endowed with real-world complexity. The problem I work on here is stratified turbulence — fluid flow under buoyancy, as in the ocean and atmosphere, where buoyancy and turbulence together mix and reorganize the fluid, shaping both the route to turbulence and the structure of fully developed turbulence. I use techniques from statistical mechanics to understand aspects such as the onset of turbulence in these flows, isolating the key physical mechanisms in a more tractable form and using them to inform qualitative features and make quantitative predictions.
- What lies beyond linear instability? Often invoked to analyze transitions to non-equilibrium states, linear instability tells us when a state is unstable, but crucially fails to answer what the long-time steady state is. Moreover, it fails to address the complex, multi-scale structure that develops (mostly non-analytically) on the way to new non-equilibrium states, and how information is processed en route to such states. I investigate this in machine learning. May's famous complexity–stability theorem in ecology predicts that large, densely interacting systems become linearly unstable as they grow, as shown using random-matrix theory. However, a neural network post training is exactly such a system and functions stably. I ask how training lets it escape this instability.
To address these problems, I combine methods from non-equilibrium statistical field theory (Martin–Siggia–Rose and Onsager–Machlup functionals), the theory of phase transitions, finite-size scaling, asymptotic analysis, stochastic modeling, and random-matrix theory.
Before UCSD, I did a Dual Degree in Engineering Physics at IIT Bombay, working on quantum condensed matter problems: with Hridis Kumar Pal, I studied topological insulator–superconductor junctions. I also spent time at TIFR Mumbai, understanding electron–phonon equilibration via non-equilibrium field theory methods, and at Aalto University, studying fluctuations in non-centrosymmetric superconductors.
Affiliations

Current
2022 – presentUC San Diego Physics
Ph.D. candidate in theoretical physics. Thesis work: transition to turbulence under body forces, stratified flows, and the statistical mechanics of machine learning.
Education
2017 – 2022IIT Bombay
Dual Degree (B.Tech + M.Tech) in Engineering Physics, specialization in Nanoscience. Master's thesis on topological insulator–superconductor junctions.
Selected Research
- Tricritical Directed Percolation Controls the Laminar–Turbulent Transition in Pipes with Body Forces
Jayasingh & Goldenfeld. Identifies the tricritical DP universality class governing pipe-flow transition under body forces; reconciles long-standing discrepancies in transition phenomenology.
Jayasingh, Kaszas, Caulfield & Goldenfeld. Finite-size scaling and Binder cumulants resolve whether stratification is a relevant perturbation to DP at the turbulent onset.
Treats trained networks as optimized interaction systems; asks whether SGD-trained dynamics violate random-matrix instability the way evolved ecosystems do.
News
- Sep 2026 Invited talk on the laminar–turbulent transition with body forces at the workshop on Turbulence in Different Media at the Simons Center for Geometry and Physics, Stony Brook (video).
- Jun 2026 AI/ML Intern at TAU Systems (Carlsbad) — physics-informed ML for laser-plasma electron accelerators.
- Dec 2025 Attended the Simons Collaboration on Wave Turbulence Annual Meeting, New York City.
- Oct 2025 Talk on tricritical DP & transitional turbulence at the JIFT Workshop on Strong Turbulence, UC San Diego.
- Sep 2025 First-author paper published in Physical Review Letters 135, 104001; covered by UCSD News.
- Mar 2025 Talk at the APS Global Physics Summit, Anaheim CA.
Honors
- Institute Silver Medal IIT Bombay · 2022
Awarded to the top-ranked student in the graduating class of each academic program.
- K. Seshia Research Excellence Award IIT Bombay · 2022
Given for the best Master's thesis in Physics, recognizing research originality and rigor.
- Physics Excellence Award UC San Diego · 2022
Departmental award from the UC San Diego Department of Physics.
- Institute Academic Prizes IIT Bombay · 2019, 2021
Annual award for the highest GPA in the Physics Department.
- Aalto Science Institute (AScI) Fellowship Finland · 2020
International research fellowship for top students in science and engineering.
- Indian Young Physicists' League — All-India Rank 3 India · 2021
National theoretical physics competition.
- KVPY Fellowship Dept. of Science & Technology, India · 2017
National fellowship for the top ~1% of science students identified for research potential.
Contact
gjayasingh@ucsd.edu · gurukalyan1.618@gmail.com
San Diego, CA