2026 Simons Collaboration on Wave Turbulence Annual Meeting

Thursday, December 3, 2026

Friday, December 4, 2026

Scott Armstrong
Sorbonne University

Anomalous Scaling of a Brownian Motion in a Log-Correlation Potential

In this talk, Scott Armstrong will study a Brownian particle with drift given by the gradient of a log-correlated Gaussian potential, proving at weak disorder convergence to a scaling limit whose law is singular with respect to Brownian motion and whose invariant measure is given by Gaussian multiplicative chaos. The proof uses a renormalization group induction; at each scale, the elliptic operator is well approximated by a Laplacian with effective diffusivity decaying as a power of scale. This is joint work with with Tuomo Kuusi and Ahmed Bou-Rabee.

Tristan Buckmaster
New York University

Blow Up for the Incompressible Euler Equations

In this talk, Tristan Buckmaster will discuss finite-time blow-up of the three-dimensional incompressible Euler equations from smooth initial data, describing a multiscale mechanism in which hydrodynamic instabilities amplify vorticity at successively smaller spatial scales. This is joint work with Levent Alpöge and Matei Coiculescu.

Eric Falcon
French National Centre for Scientific Research

Exploring Turbulent Systems Experimentally: Large-Scale Statistical Equilibrium and Kelvin-Wave Turbulence

Bridging nonequilibrium dynamics with concepts from statistical physics remains a central challenge in hydrodynamic turbulence and wave turbulence. In this talk, Eric Falcon will present experimental evidence that large scales (i.e., scales larger than the forcing scale) in both three-dimensional hydrodynamic turbulence and hydroelastic wave turbulence reach a state of statistical equilibrium (joint work with Jean-Baptiste Gorce and Marlone Vernet, respectively). This opens the way to applying tools from statistical mechanics, such as thermodynamic quantities, to the large scales of turbulent systems (joint work with Marlone Vernet and Loïc Fache).

Falcon will then turn to a different system, Kelvin waves, helical perturbations that propagate along vortex filaments. These waves are believed to play a central role in classical and quantum turbulence (in superfluids and Bose–Einstein condensates) and are also relevant to the dynamics of atmospheric vortices such as tornadoes. Yet, Kelvin waves have remained inaccessible to direct experimental observation. Here, Falcon will report the direct experimental observation of their linear dispersion relation along a single vortex in a classical fluid, consistent with Lord Kelvin’s prediction from 1880, and in the nonlinear regime, Falcon will then present experimental evidence for Kelvin-wave turbulence, showing how energy cascades from large to small scales through a mechanism (six-wave resonant interactions) predicted long ago by weak turbulence theory (joint work with Jean Barckicke and Christophe Gissinger).

Together, these results illustrate how statistical equilibrium in turbulent systems and nonlinear wave interactions shape their dynamics.

Raffaele Ferrari
Massachusetts Institute of Technology

Jupiter Polar Vortices: A GFD Playground

NASA’s Juno mission observations have revealed “vortex crystals” at Jupiter’s poles. These crystals consist of a polygonal arrangement of cyclones that precess anticyclonically around a central cyclone centered on the poles. In this talk, Raffaele Ferrari will use a one-and-a-half-layer quasi-geostrophic model to analyze the stability and anticyclonic precession of these crystals, speculating that atmospheric turbulence homogenizes planetary potential vorticity, generating an anticyclonic flow that counters the mutual advection of cyclones, which would otherwise cause the crystals to precess cyclonically. This flow also helps stabilize the crystal structures.

Jonathan Mattingly
Duke University

Batchelor Spectrum, Unexpected Dissipation in a Non-Autonomous Passive Scalar Flow, and Possibly More

In 1959, Batchelor predicted that a passive scalar that is forced at large spatial scales and advected by an incompressible flow inducing exponential growth of scalar gradients develops a universal power-law energy spectrum, now known as Batchelor’s law. In recent years, Batchelor’s law has been proven when the scalar is driven by a white-in-time stochastic forcing.

Similarly, there have been a number of works that show that randomly advected passive scalars with molecular diffusion are able to reach the theoretically maximal dissipation rate. A phenomenon often called anomalous dissipation. Both behaviors are given by the creation of ever smaller spatial structures.

In this talk, Jonathan Mattingly will discuss joint work with Tarek Elgindi and Kyle Liss to establish these results in the setting of smooth, deterministic forcing. For a specific time-periodic velocity field, Mattingly will prove that all sufficiently smooth initial scalars are attracted to a limiting solution that satisfies a cumulative form of Batchelor’s law. The forcing might be thought of as an idealization of mixing your (2D) coffee with a stirring stick by going back and forth in different directions. The proof mixes PDE and dynamical systems methods to prove the inherently stochastic nature of the underlying system.

If time permits, Mattingly will also touch on some stochastic settings related to anomalous dissipation and weak turbulence.

Nicolas Mordant
Université Grenoble Alpes

Depth Effect on Turbulence of Water Waves: Bridging Weak Turbulence and Integrable Turbulence

Reducing the water depth weakens the dispersion of surface gravity waves and enhances nonlinear effects. When weak dispersion is balanced by weak nonlinearity, the dynamics enter the regime of solitons and integrable turbulence. In contrast to weak wave turbulence, integrable turbulence does not exhibit an energy cascade, highlighting a fundamental difference between these two regimes.

In this talk, Nicolas Mordant will present an experimental study of the transition from weak wave turbulence to a shallow-water, soliton-dominated regime. The experiments were performed in a 30 m × 30 m wave tank with a water depth of 0.35 m, operated by Artelia near Grenoble, France. For technical reasons, the effective depth dependence was controlled by varying the peak frequency of the wave forcing rather than by directly changing the water depth.

The resulting wave fields were characterized using space- and time-resolved stereoscopic imaging of the free-surface deformation over a large portion of the tank. As the effective water depth was reduced, a pronounced modification of the wave spectrum was observed, both in its scale dependence and in its directional distribution. In the shallow-water regime, the wave field evolved toward a highly directional soliton gas. Concurrently, the probability distribution of the surface elevation became increasingly non-Gaussian.

These results provide insight into the transition between weak wave turbulence and integrable, soliton-dominated dynamics. Mordant will discuss also the role of finite-size effects and their possible influence on the observed transition.

Chiara Saffirio
University of Basel and University of Freiburg

Mean-Field Approximation of Many-Body Fermionic Dynamics

A major question in non-equilibrium statistical mechanics concerns the rigorous approximation of complex microscopic systems of interacting particles by means of effective macroscopic theories. While addressing non-interacting particles proves relatively straightforward, tackling systems where particles interact presents a daunting complexity, rendering many-body theory computationally non-approachable.

In this talk, Chiara Saffirio will discuss the dynamics of systems made of many interacting quantum particles and focus on the mean-field regime, i.e., weakly interacting particles whose collective effect can be approximated by an averaged potential in convolution form. Saffirio will focus on the semiclassical approximation and present a new constructive method that allows to deal with Vlasov-type systems. In particular, our technique allows to treat singular interactions.

Sergio Simonella
Sapienza University

Beyond Billiard Balls: Correlations and Kinetic Limits

Most fundamental questions on kinetic limits remain open for classical particle systems once one leaves the dilute regime. In this talk, Sergio Simonella will discuss recent progress on admissible scaling regimes and the decay of correlations for non-dilute gases, including long-range effects. Simonella will then describe some first steps towards the corresponding dynamical theory and highlight a few open problems.

Participation in the meeting falls into the following four categories. An individual’s participation category is communicated via their letter of invitation.

The Simons Foundation will never ask for credit card information or require payment for registration to our events.

Group A – PIs, Speakers & Organizers

Individuals in Group A receive travel and hotel coordination within the following parameters:

Travel
Economy Class: For flights that are three hours or less to your destination, the maximum allowable class of service is Economy class.
Premium Economy Class: For flights where the total air travel time (excluding connection time) is more than three hours and less than seven hours per segment to your destination, the maximum allowable class of service is premium economy.
Business Class: When traveling internationally (or to Hawaii/Alaska) travelers are permitted to travel in Business Class on those segments that are seven hours or more. If the routing is over budget, a premium economy or mixed-class ticket will be booked.

Hotel
Up to 3 nights at the conference hotel, arriving on Wednesday, December 2, 2026 and departing on Saturday, December 5, 2026.

Group B – Funded Participants

Individuals in Group B receive travel and hotel coordination within the following parameters:

Travel
Economy class travel will be booked regardless of flight length.

Hotel
Up to 3 nights at the conference hotel, arriving on Wednesday, December 2, 2026 and departing on Saturday, December 5, 2026.

Group C – Unfunded Participants

Individuals in Group C will not receive financial support but are encouraged to enjoy all conference-hosted meals.

Group D – Remote Participants

Individuals in Group D will participate in the meeting remotely.

Air and Rail

For funded individuals, the foundation will arrange and pay for round-trip travel from their home city to the conference city. All travel and hotel arrangements must be booked through the Simons Foundation’s preferred travel agency.

Travel Deviations

The following travel specifications are considered deviations and will only be accommodated if the cost is less than or equal to the amount the Simons Foundation would pay for a standard round-trip ticket from your home city to the conference city:

• Preferred airline
• Preferred travel class
• Specific flights/flight times
• Travel dates outside those associated with the conference
• Arriving or departing from an airport other than your home city or conference city airports, i.e. multi-segment or triangle trips.

All deviations must be reviewed and approved by the Simons Foundation and, if the cost is more than what would normally be paid, a reimbursement quote must be obtained through the foundation’s travel agency before proceeding to booking and paying for travel out of pocket. All reimbursements for travel booked directly will be paid after the conclusion of the meeting.

Changes After Ticketing

All costs related to changes made to ticketed travel are to be paid for by the participant and are not reimbursable. Please contact the foundation’s travel agency for further assistance.

Personal & Rental Cars

Personal car and rental trips over 250 miles each way require prior approval from the Simons Foundation via email.

Rental cars must be pre-approved by the Simons Foundation.

The Hotel Seville NoMad offers valet parking. Please note there are no in-and-out privileges when using the hotel’s garage, therefore it is encouraged that participants walk or take public transportation to the Simons Foundation.

Hotel

Funded individuals who require hotel accommodations are hosted by the foundation for a maximum of 3 nights at the conference hotel, arriving on Wednesday, December 2, 2026 and departing on Saturday, December 5, 2026.

Any additional nights are at the attendee’s own expense. To arrange accommodations, please register at the link included in your invitation.

Hotel Seville NoMad
22 E 29th St
New York, NY 10016
(between 28th and 29th Streets)
https://www.hyatt.com/unbound-collection/en-US/nycud-hotel-seville-nomad

For driving directions to the Hotel Seville NoMad, please click here.

Overview

In-person participants will be reimbursed for meals and local expenses including ground transportation. Expenses should be submitted through the foundation’s online expense reimbursement platform after the meeting’s conclusion.

Expenses accrued because of meetings not directly related to the Simons Foundation-hosted meeting (a satellite meeting or meeting held at another institution, for example) will not be reimbursed by the Simons Foundation and should be paid by other sources.

Below are key reimbursement takeaways; a full policy will be provided with the final logistics email circulated approximately 2 weeks prior to the meeting’s start.

Meals

The daily meal limit is $125; itemized receipts are required for expenses over $24 USD. The foundation DOES NOT provide a meal per diem and only reimburses actual meal expenses up the following amounts.

• Breakfast $20
• Lunch $30
• Dinner $75

Allowable Meal Expenses

• Meals taken on travel days (when you traveled by air or train).
• Meals not provided on a meeting day, dinner on Friday for example.
• Group dinners consisting of fellow meeting participants paid by a single person will be reimbursed up to $75 per person and the amount will count towards the $125 daily meal limit.

Unallowable Meal Expenses

• Meals taken outside those provided by the foundation (breakfast, lunch, breaks and/or dinner).
• Meals taken on days not associated with Simons Foundation-coordinated events.
• Minibar expenses.
• Meal expenses for a non-foundation guest.

• Ubers, Lyfts, taxis, etc., taken to and from restaurants in Manhattan.

  • Accommodations will be made for those with mobility restrictions.

Ground Transportation

Expenses for ground transportation will be reimbursed for travel days (i.e. traveling to/from the airport or train station) as well as subway and bus fares while in Manhattan are reimbursable.

Transportation to/from satellite meetings are not reimbursable.

Attendance

In-person participants and speakers are expected to attend all meeting days. Participants receiving hotel and travel support wishing to arrive on meeting days which conclude at 2:00 PM will be asked to attend remotely.

Entry & Building Access

Upon arrival, guests will be required to show their photo ID to enter the Simons Foundation and Flatiron Institute buildings. After checking-in at the meeting reception desk, guests will be able to show their meeting name badge to re-enter the building. If you forget your name badge, you will need to provide your photo ID.

The Simons Foundation and Flatiron Institute buildings are not considered “open campuses” and meeting participants will only have access to the spaces in which the meeting will take place. All other areas are off limits without prior approval.

If you require a private space to conduct a phone call or remote meeting, please contact your meeting manager at least 48-hours ahead of time so that they may book a space for you within the foundation’s room reservation system.

Guests & Children

Meeting participants are required to give 24-hour advance notice of any guests meeting them at the Simons Foundation either before or after the meeting. Outside guests are discouraged from joining meeting activities, including meals.

With the exception of Simons Foundation and Flatiron Institute staff, ad hoc meeting participants who did not receive a meeting invitation directly from the Simons Foundation are not permitted.

Children under the age of 18 are not permitted to attend meetings at the Simons Foundation. Furthermore, the Simons Foundation does not provide childcare facilities or support of any kind. Special accommodations will be made for nursing parents.

Meeting & Policy Questions

Christina Darras
Events Manager
[email protected]

Travel & Hotel Support

FCM Travel Meetings & Events
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