Quantum mechanics can only provide the probability of finding moving particles at the atomic level. The Schrodinger equation provides the information of a wavefunction, which gives only the quantitative prediction of probability of finding a moving particle at a particular location. Quantum mechanics appears as a strange theory, it can provide a powerful tool to explain many observed phenomena at the atomic level. Modeling of quantum mechanics using the Schrodinger equation is only one of the choices. Quantum mechanics can only provide information about moving particles in a statistical sense. For the case of “light waves,” defines the wavelength of a photon of light. This is also known as the quantum theory of light. In quantum mechanics, the wave function in the Schrodinger equation is associated with the likelihood of finding the particle at a particular time and at a particular place.
Quantum mechanics can only provide the probability of finding moving particles at the atomic level. The Schrodinger equation provides the information of a wavefunction, which gives only the quantitative prediction of probability of finding a moving particle at a particular location. Quantum mechanics appears as a strange theory, it can provide a powerful tool to explain many observed phenomena at the atomic level. Modeling of quantum mechanics using the Schrodinger equation is only one of the choices. Quantum mechanics can only provide information about moving particles in a statistical sense. For the case of “light waves,” defines the wavelength of a photon of light. This is also known as the quantum theory of light. In quantum mechanics, the wave function in the Schrodinger equation is associated with the likelihood of finding the particle at a particular time and at a particular place.
Quantum mechanics is a theory to explain and predict the behavior of particles such as electrons, protons, neutrons, atomic nuclei, atoms, and molecules, as well as the photon–the particle associated with electromagnetic radiation or light. From quantum theory we obtain the laws of chemistry as well as explanations for the properties of materials, such as crystals, semiconductors, superconductors, and superfluids. Applications of quantum behavior give us transistors, computer chips, lasers, and masers. The relatively new field of molecular biology, which leads to our better understanding of biological structures and life processes, derives from quantum considerations. Thus, quantum behavior encompasses a large fraction of modern science and technology. Quantum theory was developed during the first half of the twentieth century through the efforts of many scientists. In 1926, E. Schrödinger interjected wave mechanics into the array of ideas, equations, explanations, and theories that were prevalent at the time to explain the growing accumulation of observations of quantum phenomena. His theory introduced the wave function and the differential wave equation that it obeys. Schrödinger's wave mechanics is now the backbone of our current conceptional understanding and our mathematical procedures for the study of quantum phenomena. Our presentation of the basic principles of quantum mechanics is contained in the first three chapters. Chapter 1 begins with a treatment of plane waves and wave packets, which serves as background material for the subsequent discussion of the wave function for a free particle.
As its name suggests, Schrodinger’s equation is the brain child of Schrodinger and was first disclosed in 1926 in a paper entitled An Undulatory Theory of the Mechanics of Atoms and Molecules . Schrodinger begins by considering the dynamics of a particle moving through a force field. The Schrodinger’s equation is arrived at in an alternative heuristic path modeled after Haken. The Schrodinger’s equation is a wave equation that incorporates classical particle concepts, and classical wave function concepts, in its derivation. In other words, a heuristic approach to Schrodinger’s equation utilizes Max Planck’s quantum energy, classical kinetic energy of a free particle, and the classical “wave functions of ordinary wave optics.” Schrodinger’s equation is capable of explaining all atomic phenomena except those involving magnetism and relativity.
Till 1925 the idea of what the quantum theory would be was unknown. During 1925 three different but equivalent versions of quantum theory were proposed – Schrödinger-proposed wave mechanics; Heisenberg-developed matrix mechanics and Dirac-introduced operator theory. Considering the de Broglie’s matter waves Erwin Schrödinger, an Austrian physicist, argued that if a particle like an electron behaves as a wave then the equation of wave motion could be successfully applied to it. He postulated a function varying in both space and time in a wave-like manner (hence called wave function and denoted it as ψ). This function is generally complex and assumed to contain information about a system. Schrödinger set up a linear and time-dependent wave-like equation, called Schrödinger wave equation, to describe the wave aspect of a particle taking account of de Broglie’s relation for wavelength. Physically, |ψ(X, t)|2, where ψ(X, t) is the solution of the Schrödinger equation, is interpreted as position probability density. That is, |ψ(X, t)|2 is the probability density of observing a particle at position X at time t. ψ does not give exact outcomes of observations but helps us to know all possible events and their probabilities . Further, the probability interpretation allows us to find the average or expected result of a set of measurements on a quantum system.
The laws of quantum mechanics differ significantly from the laws of classical mechanics. The mathematical apparatus of quantum mechanics is based on the amazing Schrödinger equation. This is a specific partial differential equation with respect to a complex-valued function called the wave function. This characteristic allows, in particular, estimating the probability of finding a quantum mechanical particle in a given volume. We establish the Schrödinger equation for a free particle and for a particle moving in an external field. Then the problem of passing a potential barrier is investigated. It is shown that, in contrast to the classical case, even a relatively slow quantum mechanical particle is capable of overcoming a sufficiently high potential barrier. The Appendix considers the concept of a normalized wave function and analyzes the movement of a particle in a potential well with infinite walls.
The connection between the Schrödinger equation and Einstein's diffusion theory based on the Brownian motion of independent particles is well known. However, in contrast to diffusion theory, quantum mechanics theory has suffered controversial interpretations due to the counterintuitive concept of wavefunction. Here, while we confirm there is no difference in the mathematical form of these two equations, we derive the imaginary version of displacement. Using the diffusion theory of particles in a medium, as simple as it is, we describe that quantum mechanics is just an elegant and subtle equation to describe the probability of all the trajectories that a particle can take to propagate in time by a predictive wavefunction. Therefore, information on the position of particles through time in quantum theory is embedded in the wavefunction, which predicts the evolution of an ensemble of individual Brownian particles.
The solution (wave function) of Schrodinger’s equation is used to describe the motion of a quantum. Max Born treated the square of the absolute value of the wave function as the probability of a quantum appearing at any given point. With this statistical interpretation of a wave function, the physical meaning of the whole quantum theory becomes clearer and more understandable. The development of wave function is based on the De Broglie’s postulate: there is a matter wave related to an object. If wave functions can be explained with the statistical interpretation, then matter waves could simi-larly be explained with statiscal interpretation. This assump-tion is confirmed by deriving the Heisenburg uncertainty rela-tion through mutilplying the matter wavelength of an object Concepts of Physics, Vol. III (2006) 1 with the light wavelength of measuring medium. This new approach may offer another view to look at the reality of M. Born’s statistical interpretation of the wave function solution of Schrodinger’s equation.