According to quantum mechanics, particles at the microscopic level, such as electrons, protons, and atoms, can exhibit wave-like behavior. This wave-particle duality means that particles can exhibit both particle-like characteristics, such as localized position and momentum, as well as wave-like characteristics, such as interference and diffraction.
The behavior of macroscopic objects, on the other hand, is described by classical mechanics, where particles are treated purely as particles with well-defined positions and velocities. This classical description is typically applicable to everyday objects due to their large mass and interactions with the environment.
However, it's important to note that the wave-like behavior of particles becomes increasingly negligible as the mass and size of the objects increase. The quantum effects that are prominent at the microscopic level become practically imperceptible at macroscopic scales. This is known as the principle of correspondence, which states that classical mechanics is a valid approximation of quantum mechanics in the macroscopic limit.
In practical terms, macroscopic objects such as tables, chairs, and people can be considered stationary in our everyday experience. Their positions and velocities can be measured and predicted with a high degree of accuracy using classical mechanics. The wave-like behavior associated with microscopic particles becomes statistically averaged out at larger scales, leading to classical behavior.
So, while particles at the microscopic level can exhibit wave-like behavior, the wave-like nature becomes less relevant and negligible as we move to macroscopic objects, allowing us to treat them as classical particles with well-defined positions and velocities.