Basics of Quantum Physics

Quantum physics is the branch of science, that deals with the behavior and characteristics of matter (in the subatomic level) and energy. It is also referred to as quantum mechanics. Quantum physics is applicable to explain the fundamental nature of the universe, regarding matter and energy, for example, the nature of the particles of atom - electrons, protons and neutrons. With the development of quantum theory, queries like stability of electron orbits and black body radiation could be explained scientifically. Let's discuss in brief about the basics of quantum theory.

Basics of Quantum Physics

Max Planck, a German physicist, presented the quantum theory in 1900. Though, Max Planck presented the theory; modern quantum theory was developed, due to the contribution of many renowned scientists in the first few decades of the 20th century. In the quantum theory, proposed by Max Planck, he discovered that like matter, energy occurred in individual units and are quantifiable. He ascertained that all forms of matter emit or absorb energy in units, called quanta. Prior to this theory, it was assumed that energy existed only in the form of electromagnetic waves.

In 1905, Albert Einstein stated that not only energy, but radiation too, is quantifiable. He came to the conclusion that the energy of light depends on its frequency (E=hf, where 'E' is energy, 'h' is Planck's constant and 'f' is frequency). Louis de Broglie (French physicist), in 1924, proposed the 'principle of wave-particle duality', which stated that matter and energy are similar and there is no profound difference, in terms of their composition and behavior. According to him, both matter and energy can behave, either as waves or particles, depending upon the condition.

Erwin Schrödinger, an Austrian physicist, discovered the wave equation and contributed to the development of quantum mechanics. In 1927, Werner Heisenberg (German mathematical physicist), proposed the 'uncertainty principle'. As per this theory, it is impossible to measure the precise values of momentum and position of a subatomic particle.

This way, the modern quantum theory was developed in the early 20th century. As we have already seen, quantum physics mainly deals with waves and the subatomic particles (electrons, protons and neutrons) of matter. This is the reason, quantum theory is also referred to as quantum wave mechanics. Following are the major points that are covered in the modern quantum theory:

• Energy is discontinuous and exists in small packets, called quanta
• The subatomic particles behave as particles, as well as waves
• The subatomic particles move in a random manner
• The physical properties of the subatomic particles, like the momentum and position cannot be determined at a time. If one value is known precisely, the measurement of the other value is less accurate

Quantum theory has been one of the most important theories till date. In fact, it has opened a new dimension in physics. There is no doubt, that the theoretical basis of modern physics is centered in the two most important phenomena, namely, the theory of relativity (by Einstein) and quantum theory. Future experimentation on biological science, such as the structure of protein and other biomolecules is possible only because of quantum theory.