Max Planck's Quantum Theory

Max Planck is widely recognized as the founder of quantum physics. This German scientist was one of the most influential physicists of the 20th century, known mostly for his creation of quantum theory. Whereas Einstein's Theory of Relativity would later examine the properties of the largest matter in the universe, Planck's quantum theory focused on the nature of the tiniest subatomic particles. In 1918 he was awarded the Nobel Prize in Physics for his achievements. Planck ushered in a new era of thinking that took physics to the next level.

Old Theories

Physicists struggled to understand the interactions between matter and radiation leading up to Max Planck's discovery. Classical theories did not hold up to new observations of radiation and electromagnetics. The nature of light proved to be particularly complex. Some scientists incorrectly considered light to be a continuous wave of electromagnetic energy flowing like an unbroken stream of water. Planck's observations would bring some clarity to the issue.

Planck's Theory

Max Planck presented his quantum theory in 1900, revolutionizing modern physics. He demonstrated that light and radiation are not emitted continuously in a constant amount from all matter. Planck suggested that light and radiation are emitted and absorbed in distinct amounts by different subatomic particles in all matter. These findings were based on his careful observation of blackbody radiation. The radiation frequencies of matter were shown to depend on energy atoms known as photons. Planck had discovered a mathematical formula supporting the idea that energy is always emitted or absorbed in discrete units referred to as quanta. Therefore, light is produced and absorbed in different quanta depending on the atomic structure of matter.

Implications

Planck's quantum theory changed the face of physics, contradicting traditional concepts about the properties of radiation, energy and light. He came up with the revolutionary idea that atomic structure determined the internal properties of matter as well as the nature of the energy and light emitted by matter.

Impact on Later Theories

Quantum theory had an impact on many of the physicists that followed Planck's lead in the 20th century. Albert Einstein used the theory in 1905 to develop his concept of the photoelectric effect of energy. Other scientists continued to study the role of the atom in relation to radiation and light. Niels Bohr, another physicist, later relied on Planck's assertion that atoms have discrete energy values when he developed his atom model and successfully analyzed the spectrum of the hydrogen atom.

The Big Picture

Our current understanding of molecules and atoms is largely due to the foundation laid by Planck and his contemporaries. Quantum physics has been used to develop new energy sources, construct devastating bombs and hypothesize about the birth of the universe. Much remains unknown, but quantum theory will certainly continue to play a role as scientists push to learn more about the world in which we live.

References

• Space and Motion
• The Big View