Splashing of drops, frictional slip on a tectonic fault, cracking of drying paint and formation of biofilms, are all examples of fascinating and important phenomena that occur at interfaces. Understanding the physical processes that take place at interfaces is fundamental, but the physical details are often obscured by the bulk and are thus difficulty to study. The simultaneous contribution of processes occurring on many time scales and many length scales make computational approaches almost impossible and direct experiments very difficult. Most studies of interfaces focus on important processes occurring at or near equilibrium, yet often dynamics at interfaces under conditions that are far from equilibrium hold beautiful mysteries: The generation of a splash when a liquid drop impacts a surface, hydrodynamic and electro-hydrodynamic instabilities, friction and fracture, Laplacian growth and even the formation of biofilms are all interesting systems with both fundamental and technological importance. We are interested in understanding non-linear dynamics of mostly soft and liquid systems.


A crumpled piece of paper is a familiar everyday object for most people, especially for anyone doing research. In addition to their role as graves for failed theories and ideas, the shape of crumpled papers and their networks of creases hold many mysteries.


In many natural environments, bacteria collectively aggregate to exist in densely populated and structurally diverse communities called biofilms. We have much to learn from these colonies ranging from cell to cell communication to emergent behavior from small building blocks.

Vortex Ring Collisions

Vortex rings are an intriguing marvel of fluid dynamics that are ubiquitous throughout nature. Probing collision of two such rings - with effects on many length scales - could reveal new secrets in fluid dynamics.

Swirling of Granular Media

The flow behavior of granular material is fascinating because under certain circumstances it behaves like a fluid while under other circumstances it behaves like a solid. Technical knowledge is important for the control of mixing, unmixing, release from storage, transport of goods ranging from powders to pills to gravel.

Aging and Memory in Disordered Systems

Crumpled sheets, elastic foams and granular materials exhibit a similar repertoire of glassy-like behaviors when driven far from equilibrium. These systems also allow probing of the underlying structural dynamics, which we exploit in search of a deeper understanding of these behaviors.


Friction is everywhere – it keeps your car on the road, your coffee cup in your hand, and your feet beneath you. For such a ubiquitous phenomenon, we still have many questions left to answer.

Hydraulic Fracture

We are interested in the material properties that govern the scale, extent and morphology of hydraulic fractures in brittle materials. We aim to study fluid driven crack propagation in hydrogels, where the time scale of these fractures is slow enough that we can study the dynamics of the fracture as well.

Liquid Droplet Impact and Splashing

When it rains, it pours. And when it pours, drops splash on the sidewalk. Why such liquid drops splash (or bounce!) on solid surfaces is a surprisingly deep question.