The concept of wave-particle duality in quantum mechanics can be complex to understand. In quantum theory, particles are described by wave functions, which are mathematical functions that represent the probability distribution of finding the particle in different states. The wave function undergoes a process called collapse or reduction when the particle is observed or measured, leading to the particle being observed in a definite state.
However, it's important to note that the wave function collapse is not limited to conscious observation. Any interaction with the environment, such as a particle interacting with other particles or being detected by an instrument, can cause the collapse of the wave function.
In the context of everyday macroscopic objects, such as the particles that make up our existence, their wave functions effectively collapse due to the numerous interactions they have with their surroundings. The environment constantly interacts with these particles, causing their wave functions to collapse and behave more like classical particles rather than extended wave-like entities.
The process of wave function collapse is still an area of active research and interpretation within quantum mechanics. Various interpretations, such as the Copenhagen interpretation or the many-worlds interpretation, provide different explanations for the collapse process. However, regardless of the interpretation, it is generally agreed upon that macroscopic objects and the particles that constitute them behave classically due to their strong interactions with the environment, which effectively "observe" them and cause the collapse of their wave functions.
In summary, macroscopic objects, including the particles that make up our existence, exhibit classical behavior because they interact strongly with their environment, causing their wave functions to collapse and behave as particles rather than extended wave-like entities.