Walter Kohn Biography Quotes 11 Report mistakes

Early Life and Background
Walter Kohn was born in Vienna, Austria, in 1923, into a Jewish family whose aspirations for education and cultural life were shattered by the political upheavals of the 1930s. After the 1938 Anschluss, anti-Jewish laws rapidly narrowed every horizon, closing schools and careers and placing families in immediate danger. In 1939, as a teenager, Kohn escaped on a Kindertransport to Britain. He was separated from his parents and many relatives; the Holocaust would destroy the world he had known. With the outbreak of war, Britain classified many refugees as enemy aliens, and Kohn, like others, was sent to Canada and interned. Even in the camp, his drive to study persisted. He learned from fellow internees and volunteer teachers, salvaging an education under makeshift conditions until he was released to attend university.

Education and Training
Kohn enrolled at the University of Toronto, where faculty recognized his talent and helped him accelerate through a demanding curriculum in mathematics and physics. He emerged not only with strong analytical skills but also with a perspective shaped by displacement and resilience. Graduate study took him to Harvard University, where he worked under the guidance of Julian Schwinger, then one of the most brilliant theorists in the world. Schwinger's rigorous approach to field theory and scattering left a lasting imprint on Kohn's taste for precise variational principles and clean mathematical formulations. Kohn's early research traversed nuclear and many-body physics, providing tools he later recast for the quantum theory of solids.

Early Career and Solid-State Breakthroughs
Kohn began his academic career at Carnegie Institute of Technology (now Carnegie Mellon University), turning decisively toward condensed matter physics. The 1950s were a formative period: quantum mechanics was established, but the electronic structure and transport of real materials remained a notoriously difficult frontier. Kohn thrived in this environment, showing a talent for identifying deep, general principles with practical computational consequences. Partnering with J. M. Luttinger, he formulated the Luttinger-Kohn representation in band theory, which clarified how to describe electrons in semiconductors near band edges. With Norman Rostoker, he developed a powerful scattering approach to electronic structure, linked to the earlier insights of Jan Korringa; the Korringa-Kohn-Rostoker (KKR) method became a cornerstone for computing band structures and understanding alloys. He identified the Kohn anomaly in phonon dispersion, illuminating subtle signatures of electron-phonon coupling in metals, and articulated what became known as the Kohn theorem, constraining the cyclotron resonance of interacting electron systems. These contributions, both conceptual and methodological, helped transform solid-state physics from an art of approximations into a systematic, predictive science.

From Many-Body Complexity to Density Functional Theory
Kohn's most celebrated work addressed the central challenge of many-electron systems: the exponentially hard task of solving the Schrödinger equation for interacting electrons in real materials. Collaborating with Pierre Hohenberg, he proved the Hohenberg-Kohn theorems, establishing that the ground-state electron density uniquely determines all properties of an interacting electronic system and that a variational principle exists in terms of this density. This result did more than shift variables; it reoriented the problem toward the electron density as a fundamental variable, opening a path for practical approximations. Soon after, with Lu Jeu Sham, Kohn devised the Kohn-Sham scheme, an ingenious construction that replaces the intractable interacting system with a fictitious noninteracting one producing the same ground-state density. The Kohn-Sham equations, coupled with carefully designed exchange-correlation functionals, yielded a versatile framework that could be implemented on then-emerging computers. Over subsequent decades, this density functional theory (DFT) made it possible to calculate structures, energetics, vibrations, and responses of molecules and solids with unprecedented reliability. The broad impact of these ideas spanned physics, chemistry, and materials science, and in recognition of this transformative reach Kohn received the 1998 Nobel Prize in Chemistry, sharing the honor with John A. Pople, whose quantum-chemical methods complemented DFT in the computational revolution of the late twentieth century.

Institution Building and Mentorship
In the 1960s Kohn joined the University of California, San Diego, where he helped build a major center in condensed matter theory during a period when the campus also attracted distinguished figures such as Maria Goeppert Mayer. The intellectual climate of La Jolla was ideal for the cross-pollination of ideas that DFT exemplified, and Kohn's collaborations with Hohenberg and Sham took shape within this vibrant environment. Later, Kohn moved to the University of California, Santa Barbara, where he became the founding director of the Institute for Theoretical Physics. That institute, conceived as a hub where theorists from around the world could gather for extended programs, nurtured fields from condensed matter to particle physics and cosmology. Kohn's leadership emphasized openness, depth, and community, values he had learned from mentors like Schwinger and from peers whose work he admired, including practitioners in both physics and chemistry who were pushing computation to new realms.

Engagement Beyond the Laboratory
Kohn never saw science as isolated from society. Marked by early exile and loss, he was keenly aware of the ethical dimensions of knowledge and the obligations of scientists in public life. In later years he advocated for renewable energy and the responsible stewardship of the planet, urging colleagues and students to apply rigorous thinking to climate and resource challenges. With writer and historian John Perlin, he helped bring to broader audiences the science and history of solar energy, connecting fundamental physics to urgent practical needs. He wrote and spoke widely about the role of education in fostering both creativity and conscience, often crediting the teachers and colleagues who had sustained him from internment through the heights of scientific recognition.

Legacy and Influence
Walter Kohn's legacy lives in the daily work of researchers who use DFT and its descendants to design catalysts, understand biomolecules, predict novel materials, and interpret spectroscopies. The Hohenberg-Kohn theorems and Kohn-Sham equations underpin software used across academia and industry, while the Luttinger-Kohn model, the KKR method, the Kohn anomaly, and the Kohn theorem remain staples of modern condensed matter theory. Equally enduring is the example he set as a builder of institutions and communities, and as a scientist whose life bridged continents and disciplines. Born in Vienna in 1923, he endured the ruptures of the twentieth century and reshaped a central domain of physics and chemistry. He died in 2016, having left a body of work that continues to define how we connect quantum mechanics with the tangible properties of matter, and a human story that continues to inspire those who see in science both a search for truth and a commitment to the common good.

Our collection contains 11 quotes who is written by Walter, under the main topics: Ethics & Morality - Learning - Military & Soldier - Peace - Science.