Ramin Golestanian

Ramin Golestanian is an Iranian theoretical physicist whose work has helped to define a new field of physics: the study of active matter, the science of systems made of many small units that consume energy and move on their own. From microscopic swimming machines to the collective motion of living cells, his theories have given researchers a mathematical language to describe matter that is, in a deep sense, alive with motion. He is one of the directors of the Max Planck Institute for Dynamics and Self-Organization in Göttingen, Germany, where he leads the Department of Living Matter Physics, and he holds a position at the University of Oxford. His career is a study in patient, fearless curiosity about questions that sit on the border between physics and life.

Golestanian was born in Tehran in 1971 and grew up in Iran during years of great upheaval. He studied physics at the Sharif University of Technology in Tehran, one of the most demanding scientific institutions in the country, earning his bachelor's degree and then his master's degree there. It was a place where talented young people were trained to think deeply and to take nothing for granted, and Golestanian absorbed that habit of careful reasoning. He went on to complete his doctorate at the Institute for Advanced Studies in Basic Sciences in Zanjan, Iran, before moving abroad to continue his research. This path is itself instructive: world-class science can begin anywhere, including in a young man's studies in his home country, far from the famous laboratories of Europe and America.

After his doctorate he took up research positions in some of the leading centers of theoretical physics, including a fellowship at the Kavli Institute for Theoretical Physics in the United States and work at the Massachusetts Institute of Technology. He then built his independent scientific career in the United Kingdom, first at the University of Sheffield and later at the University of Oxford, where he became a professor of theoretical physics. In 2018 he was appointed a director at the Max Planck Institute for Dynamics and Self-Organization, one of Germany's most prestigious research organizations, founding and leading a department devoted entirely to the physics of living matter. To rise to such a position is rare, and it reflects how seriously the international community takes his ideas.

The central thread of Golestanian's work is the physics of motion at very small scales, where the ordinary intuition of swimming and pushing breaks down. A bacterium or a microscopic droplet lives in a world dominated by viscosity, where water feels as thick as honey and momentum counts for almost nothing. To move at all in such a world, a tiny object cannot simply paddle the way a fish does; it must change its shape in clever, irreversible ways, or it must convert chemical energy directly into motion. Golestanian has been one of the people who worked out, with mathematical precision, how such motion is possible and what rules govern it.

One of his most influential contributions was the theory of self-phoretic motion, the idea that a small particle can propel itself by creating, through chemical reactions on its own surface, a gradient in its surroundings that then pushes it forward. Working with collaborators, he helped explain how artificial microswimmers, sometimes only a few thousandths of a millimeter across, can swim through a fluid by catalyzing a reaction on one side of their surface. These ideas were not only beautiful in theory; they were soon connected to real experiments in which tiny engineered particles were observed swimming exactly as the equations predicted. This bridge between abstract calculation and laboratory observation is a hallmark of his style.

Golestanian also developed deep insights into how many such active particles behave together. A single self-propelled particle is interesting, but a crowd of them can do something astonishing: they can spontaneously organize, gathering into clusters, forming patterns, and behaving collectively in ways that no single particle could. He helped show that the chemical signals these particles emit and sense can make them attract or repel one another, leading to a rich variety of self-organized structures. This work pointed toward a unifying way of thinking about systems as different as schools of bacteria, colonies of cells, and swarms of synthetic robots, all governed by the same underlying physics of activity and feedback.

His research has reached even into the chemistry of life itself. He and his collaborators proposed that enzymes, the protein machines that carry out the reactions inside our cells, may themselves be set into motion by the very reactions they catalyze, and that populations of such enzymes might organize their own movement and distribution. These ideas connect the physics of tiny swimming machines to the inner workings of living organisms, suggesting that the boundary between the physics of the inanimate and the science of life is far more porous than we once believed. It is the kind of question that rewards a thinker willing to cross the borders between disciplines.

What makes Golestanian's career exemplary is not only the cleverness of his theories but the spirit in which he pursues them. He is known among colleagues as a generous collaborator and a devoted mentor, someone who builds teams and raises up younger scientists rather than seeking glory alone. The community of active-matter physics that has grown up around the world owes a great deal to his willingness to share ideas, to ask the next good question, and to encourage others to attempt it. His many honors, including major fellowships and prizes in physics, recognize both his discoveries and his role in shaping a field.

There is a quiet lesson in his life for anyone who values knowledge. The Islamic intellectual tradition has long held that the careful study of the natural world is a way of contemplating the order and wisdom written into creation. Golestanian's work, examining how the smallest pieces of matter come alive with motion and organize themselves into patterns, is in this spirit a study of the astonishing intricacy of the world. He did not chase fashionable problems; he followed his curiosity into a difficult and unfamiliar territory and stayed there long enough to map it. That patience, combined with mathematical honesty and an open hand toward collaborators, is the model of a scientist at his best.

Today Ramin Golestanian stands among the leading theoretical physicists of his generation, an Iranian-born scholar whose ideas are taught, tested, and extended in laboratories across the world. His journey from the classrooms of Tehran to the directorship of a Max Planck institute reminds us that the love of understanding knows no borders, that great science can begin in modest circumstances, and that the universe, even at its smallest and most restless scales, rewards those who study it with patience, rigor, and wonder.