Quantum physics is that branch of physics that describes the behavior of energy at the atomic and subatomic levels. Newton’s Three Laws may provide a more-or-less accurate description of nature as we perceive it on Earth, but they cannot explain Mercury’s orbit around the sun. It fell to Einstein’s Theory of Relativity to provide this explanation.
However, there were gaps in Einstein’s theories as well. The Theory of General Relativity explains the relationship between energy and matter, but it cannot explain the fact that the universe appears to be expanding at an accelerated rate. Quantum physics provides an explanations for this phenomenon.
It may seem counterintuitive, but according to quantum mechanics, everything in the universe has a dual nature in that it is simultaneously both a particle and a wave. Additionally, it is impossible to predict any outcome with certainty; you can only predict the probability of a particular outcome. Finally, all energy is bundled into discrete packets. These three descriptions, when expressed mathematically, are the cornerstones of quantum theory.
Einstein was one of the first scientists to introduce the dual nature of particles and “discreteness” into physics in 1905 when he offered an explanation for the photoelectric effect. Beams of light, Einstein theorized, were not just waves with a set frequency but an actual stream of light particles, which Einstein referred to as “quanta.” Today, we use the term “photons” to describe discrete packets of light. Einstein’s work with photons eventually led to the development of lasers. Without lasers, there would be no photoelectric eyes, and medical science would have not had access to a piece of lifesaving equipment.
Why Is Quantum Mechanics Important?
Quantum physics has provided the theoretical framework for many of the technological innovations that have transformed contemporary life. Transistors and semiconductors would not have been developed without quantum theory, and without transistors, there would be no personal computers and no smart phones.
Another invention that would not be possible without quantum physics is the atomic clock. The Global Positioning System (GPS) technology you rely upon to keep from getting lost depends upon atomic clocks that are synchronized throughout a network of satellites.