Updated: Oct 8
Author: Srijanita Maurya
Quantum mechanics is one of the most difficult and fascinating branch of physics. It is a field of physics concerned with the atomic and subatomic behavior of matter and energy. Quantum physics concepts have revolutionized our knowledge of the cosmos, but they also call into question our intuition about how the world works.
The wave-particle duality is a fundamental concept of quantum physics. Matter and energy can behave in both wave-like and particle-like ways, according to this concept. Thomas Young discovered the wave nature of light in 1801, when he conducted an experiment to illustrate the interference of light waves. A beam of light was sent through a tiny slit in the experiment and then projected onto a screen. If light were just a particle, it would create a bright spot on the screen just behind the slit. The light, on the other hand, created a pattern of bright and dark patches, indicating that it was acting like a wave. This experiment offered the first proof that light had wave-like qualities. According to quantum physics, light actually has dual nature. Light is neither particle nor wave, but acts like both.
The wave-particle duality does not just apply to light. In reality, it holds true for all matter and energy. Electrons, which are particles, can, for example, display wave-like behavior. Clinton Davisson and Lester Germer discovered this in 1927 while conducting an experiment in which an electron beam was diffracted by a crystal. In this experiment, the electrons generated a diffraction pattern comparable to the pattern produced by light. This demonstrated that electron exhibit wave-like qualities. This concept is essential to understanding the behavior of matter and energy at the atomic and subatomic levels, and it is crucial to the study of quantum mechanics.
Superposition is another important concept in quantum physics. A quantum system can exist in several states at the same time, according to this concept. Erwin Schrödinger initially proposed this idea in 1926, in his famous thought experiment known as Schrödinger's cat. A cat is placed in a confined cage with a vial of toxic gas in this thought experiment. The vial is linked to a Geiger counter, which measures radioactive atom disintegration. If the atom decays, the toxic gas is released, killing the cat. However, until it is noticed, the atom persists in both a decayed and undecayed state, according to the principle of superposition. As a result, until the box is opened and the atom is detected, the cat is both alive and dead. This thought experiment emphasizes quantum physics' perplexing and paradoxical nature. It calls into question our notion of reality by implying that particles might exist in numerous states simultaneously until they are detected.
The superposition principle is also important in the development of quantum computers. A bit in conventional computing can only exist in one of two states: 0 or 1. In quantum computing, however, a qubit may exist in several states at the same time. As a result, quantum computers can compute significantly faster than conventional computers.
Entanglement is one of the most important concepts in quantum physics. Entanglement is essential in quantum communication and quantum computation. Using entangled particles, information may be safely conveyed via quantum communication. When two particles are entangled, the state of one particle is determined by the state of the other particle, regardless of the distance between them. Albert Einstein, Boris Podolsky, and Nathan Rosen discovered this concept in their famous EPR (Einstein-Podolsky-Rosen) conundrum in 1935. Two entangled particles are created and then separated by a vast distance in the thought experiment. When one particle's state is measured, the state of the other particle is instantaneously known, regardless of their distance. This phenomenon is known as "spooky action at a distance," and it calls into question our notion of causality and locality.
Despite the difficulties that quantum mechanics presents, it offers a wide range of practical applications. It is utilized in the creation of modern electronics like transistors and integrated circuits, for example. It is also used in medical imaging, such as MRI, and in the discovery of novel materials, such as superconductors.
To summarize, quantum mechanics is one of the most difficult and fascinating theory in the area of physics. It calls into question our assumptions about how the world operates and our perceptions of reality. It does, however, offer a wide range of practical applications that have transformed our knowledge of the world and have the potential to alter our technology and civilization. Despite its difficulties, quantum mechanics remains an important field of study for physicists and scientists working in a range of domains.
Books and websites for reference
1. "Principles of Quantum Mechanics" by R. Shankar
2. "Introduction to Quantum Mechanics" by David Griffiths
3. "Quantum Mechanics: Concepts and Applications" by Nouredine Zettili
4. "Quantum Mechanics: A Modern Development" by Leslie E. Ballentine
5. "Quantum Mechanics: The Theoretical Minimum" by Leonard Susskind and Art Friedman
6. Phys.org: https://phys.org/physics-news/quantum-physics/
8. MIT OpenCourseWare: https://ocw.mit.edu/courses/physics/8-04-quantum-physics-i-spring-2013/
9. Stanford Encyclopedia of Philosophy: https://plato.stanford.edu/entries/qt-issues/