Matter wave
![Propagation of de Broglie waves in 1d – real part of the complex amplitude is blue, imaginary part is green. The probability (shown as the color opacity) of finding the particle at a given point x is spread out like a waveform; there is no definite position of the particle. As the amplitude increases above zero the curvature decreases, so the amplitude decreases again, and vice versa. The result is an alternating amplitude: a wave. Top: plane wave. Bottom: wave packet.](/Images/godic/202501/08/Propagation_of_a_de_broglie_wave.svg0319.png")
![Demonstration of a matter wave in diffraction of electrons](/Images/godic/202501/08/Wave-particle_duality0319.gif")
All matter can exhibit wave-like behavior. For example, a beam of electrons can be diffracted just like a beam of light or a water wave. Matter waves are a central part of the theory of quantum mechanics, being an example of wave–particle duality. The concept that matter behaves like a wave is also referred to as the de Broglie hypothesis (/dəˈbrɔɪ/) due to having been proposed by Louis de Broglie in 1924. Matter waves are often referred to as de Broglie waves.