The wave-particle duality of photons, as hypothesized by Einstein, was well accepted by the early 1920's. De Broglie's bold hypothesis in 1924, that all matter likewise has a wave-particle duality added further fuel to the fire in the development of Quantum Mechanics. It seared into the minds of physicists the wave-particle duality of Nature. Needless to say, this counter intuitive and bold assertion mystified the World beyond any sensible comprehension by common sense. The question often asked by ordinary people is what is the matter with de Broglie waves? We provide just this answer and demystify this 'matter' in this short paper.
The wave-particle duality of photons, as hypothesized by Einstein, was well accepted by the early 1920's. De Broglie's bold hypothesis in 1924, that all matter likewise has a wave-particle duality added further fuel to the fire in the development of Quantum Mechanics. It seared into the minds of physicists the wave-particle duality of Nature. Needless to say, this counter intuitive and bold assertion mystified the World beyond any sensible comprehension by common sense. The question often asked by ordinary people is what is the matter with de Broglie waves? We provide just this answer and demystify this 'matter' in this short paper.
In 1923 Louis de Broglie introduced the notion of matter waves, the particle-wave duality of matter which is the reciprocal extension of the notion of the particle-wave duality of light. The wave nature of matter is evidently a memory of its origin in light, much as the particle aspect of light suggests its capacity to create matter. Such dualities are part of the connective tissue of the Cosmos and its two principle energy forms, light and matter (free and bound electromagnetic energy). The less massive the particle, the more strongly is its wave nature expressed. The wave nature of the tiny electron is very pronounced, as is famously demonstrated by the interference phenomena of the canonical 2-slit experiment of quantum mechanics. In the extreme case of neutrinos, which apparently have almost no mass, their wave nature completely dominates their particle nature. However, as particles become heavier and more massive, their wave nature becomes rapidly overwhelmed, until for ordinary macroscopic masses to which we are sensible it is completely obscured.
Bohr's response in 1925 to the failure of the Bohr–Kramers–Slater theory was, as we have seen, to regard wave–particle duality as having a formal, rather than realistic, significance; he saw it as a ‘limitation of our usual means of visualization’. That same year, however, wave–particle duality was generalised by Louis-Victor de Broglie to cover the theory of matter. Moreover, the advent of quantum mechanics (i.e. matrix mechanics and wave mechanics), rather than dispelling the duality problem, heightened it. How did Bohr respond to these new developments in the quantum theory? A matter of waves In the autumn of 1923 de Broglie put forward the extremely bold hypothesis that any particle whatever is associated with a wave whose wavelength λ and frequency ν are proportional to the particle's momentum and energy respectively: λ = h / p , v = E / h . De Broglie regarded his hypothesis as the basis of a new mechanics, a wave mechanics related to classical mechanics in the same way as wave optics is related to ray optics. On this view the trajectory of a particle corresponds to the ray of the wave associated with it (i.e. the normal to the equiphase surface of the wave), and the velocity of the particle corresponds to the group velocity of the wave. De Broglie suggested, moreover, that in certain circumstances particles should exhibit diffraction effects: a stream of electrons, for example, which passes through a slit in a screen should undergo diffraction.
Louis de Broglie put forward the idea of wave-particle duality in 1923-24, less than two years before the advent of Quantum Mechanics. This last theory assumes that duality, but in a more abstract and counter-intuitive manner than de Broglie did. In this article the wave behavior of matter is presented in a didactic way following de Broglie´s ideas. This kind of presentation may (hopefully) be helpful to better understand the quantum features in a more intuitive way. It is shown that this wave mechanics, in the framework of the theory of relativity, is compatible with Planck´s quantum and explains as well the particle´s dynamics, provided the uncertainty relations are properly incorporated. The main difficulty with this view lies in its interpreting the wave as a non-local entity
The development of the quantum theory has been on -going for many years.The wave -particle duality has been and is central to debates among physicists, in their endeavor to understand and bring more insight about the quantum theory.In this paper attempts by physicists to clarify the wave -particle duality are discussed.The wave or particle or both state of matter is analyzed, followed by discussion on the criticisms on de Broglie equation.Lastly, the paper concludes that debates on the wave -particle duality will continue since there is no consensus yet among physicists, and that experimental evidence should be given to substantiate claims.
Where did we get that [equation] from? Nowhere. It is not possible to derive it from anything you know. It came out of the mind of Schrödinger. Richard Feynman De Broglie's matter waves The early struggles of physicists towards a quantum theory were mostly concerned with attempts to understand the nature of light. The traditional picture of light as a wave motion had been challenged by Planck and Einstein. They had shown that certain experimental results that were impossible to understand in terms of a wave picture could be easily explained if light was thought of as a stream of particles, now called photons. William Bragg, who, with his son, won the 1915 Nobel Prize for studies of crystal structure using X-rays, summarized this dilemma for physics by exclaiming in despair that he was teaching the corpuscular theory of light on Mondays, Wednesdays and Fridays, and the undulatory theory on Tuesdays, Thursdays and Saturdays! Physicists were still wrestling with these apparently contradictory properties of light when, in 1924, Prince Louis de Broglie (pronounced ‘de Broy’) suggested that all matter, even objects that we usually think of as particles – such as electrons – should also display wavelike behaviour! This revolutionary idea was completely unexpected and, what is more, was included by de Broglie in his Ph. D. thesis. Like most people, physicists are generally reluctant to accept any wild new idea, especially if there is not a shred of evidence to support it.
This chapter examines the wave properties of matter. Early attempts to extend the quantum ideas to the theory of matter had some limited success, but did not progress very far. Another radical idea was required before a satisfactory theory could be developed. As light has both wave and particle properties, perhaps the same is true of 'ordinary' particles such as electrons. This bold suggestion was made by Louis de Broglie in 1923, and within a few years it had been confirmed experimentally. De Broglie's wave hypothesis formed the basis for Schrödinger's equation, which was found capable of predicting the allowed energy levels in atoms and molecules, and must be regarded as one of the most important mathematical equations of modern science. Before discussing these ideas, the chapter begins by considering the classical mechanics of particles, reviewing some simple concepts that form an essential background to the quantum theory of matter.