Max Planck

In a career that lasted seven decades, Max Planck achieved an enduring legacy with groundbreaking discoveries involving the relationship between heat and energy, but he is most remembered as the founder of the "quantum theory."

PlanckJust as Albert Einstein forever changed the perception of relationship between space and time with his “theory of relativity,” Planck did the same for knowledge of atomic and subatomic processes.

A gifted musician, the German-born Planck showed early promise in the piano, organ and cello, even composing songs and operas, but he ultimately decided that his critical thinking skills were best suited for theoretical physics. At the University of Munich, Planck quickly grasped complex subject matter, earning his doctorate at the young age of 21. He soon took a teaching position at the University of Berlin, and lectured on all branches of theoretical physics.

Focusing on thermodynamics (the study of heat and energy), Planck was especially interested in the nature of radiation from hot materials. He developed a theory that comprehensively characterized the experimental evidence, but some of it was contrary to the popular scientific belief of the time. He asserted that energy flows were not steady, but rather moved as distinct bursts he termed “quanta”. Among other things, this helped explain why the same piece of iron could glow red on one side and white on the other — evidence, he said, of differing levels of quanta activity.

Planck found that although quanta activity (energy) varied it was still equivalent to radiation levels multiplied by a universal constant: “Planck’s constant,” as it was. These findings came to be known as quantum theory, which provides a theoretical foundation for the relationship and tendencies of matter and energy on atomic and subatomic levels. Planck won the 1918 Nobel Prize in recognition of his groundbreaking work.

During the years following his most celebrated discovery, Planck would continue his research in optics, thermodynamics and physical chemistry. In addition, it was partly through his promotional efforts that the special theory of relativity put forth by Einstein was able to make its way into the scientific mainstream.

Planck’s discoveries have gained in stature as new generations of scientists have verified his findings and used them to advance their own research. Planck seemed to forecast such a turn of events when he once observed, “A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents die, and a new generation grows up that is familiar with it.”