Max Planck Formulates Quantum Theory

Max Planck, German theoretical physicist who discovered quantum theory.
German theoretical physicist Max Planck (1858 - 1947), who formulated the quantum theory and was awarded the Nobel prize for Physics in 1918. (Photo by Hulton Archive/Getty Images)

In 1900, German theoretical physicist Max Planck revolutionized the field of physics by discovering that energy does not flow evenly but is instead released in discrete packets. Planck created an equation to predict this phenomenon, and his discovery ended the primacy of what many people now call "classical physics" in favor of the study of quantum physics.

The Problem

Despite feeling that all was already known in the field of physics, there was still one problem that had plagued physicists for decades: They could not understand the surprising results they continued to get from heating surfaces that absorb all frequencies of light that hit them, otherwise known as black bodies.

Try as they might, scientists could not explain the results using classical physics.

The Solution

Max Planck was born in Kiel, Germany, on April 23, 1858, and was considering becoming a professional pianist before a teacher turned his attention to science. Planck went on to receive degrees from the University of Berlin and the University of Munich.

After spending four years as an associate professor of theoretical physics at Kiel University, Planck moved to the University of Berlin, where he became a full professor in 1892.

Planck's passion was thermodynamics. While researching black-body radiation, he too kept running into the same problem as other scientists. Classical physics could not explain the results he was finding.

In 1900, 42-year-old Planck discovered an equation that explained the results of these tests: E=Nhf, with E=energy, N=integer, h=constant, f=frequency. In determining this equation, Planck came up with the constant (h), which is now known as "Planck's constant."

The amazing part of Planck's discovery was that energy, which appears to be emitted in wavelengths, is actually discharged in small packets he called "quanta".

This new theory of energy revolutionized physics and opened the way for Albert Einstein's theory of relativity.

Life After Discovery

At first, the magnitude of Planck's discovery was not fully understood.

It wasn't until Einstein and others used quantum theory for even further advancements in physics that the revolutionary nature of his discovery was realized.

By 1918, the scientific community was well aware of the importance of Planck's work and awarded him the Nobel Prize in Physics.

He continued to conduct research and contribute further to the advancement of physics, but nothing compared to his 1900 findings.

Tragedy in His Personal Life

While he achieved much in his professional life, Planck's personal life was marked by tragedy. His first wife died in 1909, his oldest son, Karl, during World War I. Twin girls, Margarete and Emma, both later died in childbirth. And his youngest son, Erwin, was implicated in the failed July Plot to kill Hitler and was hanged.

In 1911, Planck did remarry and had one son, Hermann.

Planck decided to remain in Germany during World War II. Using his clout, the physicist tried to stand up for Jewish scientists, but with little success. In protest, Planck resigned as president of the Kaiser Wilhelm Institute in 1937.

In 1944, a bomb dropped during an Allied air raid hit his house, destroying many of his possessions, including all his scientific notebooks. 

Max Planck died on October 4, 1947, at the age of 89.

mla apa chicago
Your Citation
Rosenberg, Jennifer. "Max Planck Formulates Quantum Theory." ThoughtCo, Mar. 8, 2018, Rosenberg, Jennifer. (2018, March 8). Max Planck Formulates Quantum Theory. Retrieved from Rosenberg, Jennifer. "Max Planck Formulates Quantum Theory." ThoughtCo. (accessed March 21, 2018).