%0 Journal Article %T About the Nature of De Broglie Wave %A Isaak Man¡¯kin %J Open Access Library Journal %V 9 %N 4 %P 1-4 %@ 2333-9721 %D 2022 %I Open Access Library %R 10.4236/oalib.1108655 %X In this article, it is shown that if a particle is at rest and has some harmonic oscillation, then a traveling particle with a constant speed corresponds to a De Broglie Wave. In 1924, De Broglie proposed that particles of matter exhibit wave like behavior, the expression for which became fundamental in the creation of wave mechanics (quantum mechanics). The main equation for this is the Schrödinger equation, which in the case of free motion of a particle becomes the expression for the De Broglie wave. This hypothesis is supported by many early experiments on the diffraction of electrons, and later the development of modern physics. However until now, the origin of this hypothesis remains unclear. We show that the expression for the De Broglie wavelength can be obtained from a more general well-known concept, that any particle at rest has a corresponding harmonic oscillation that transforms into a wave of a moving particle with the help of relativistic change of coordinates (the Lorentz transformations). In this way, a De Broglie wave can be explained as a spacetime wave. %K De Broglie Wave %K Lorentz Transformation %K Quantum Mechanics %U http://www.oalib.com/paper/6772625