According to the principles of quantum mechanics, particles such as electrons can exhibit both wave-like and particle-like properties, regardless of whether they are being observed or perceived. This is known as wave-particle duality.
When a particle is not being observed or measured, its behavior is often described by a wave function, which represents the probability distribution of finding the particle in different states or locations. This wave function can exhibit wave-like characteristics, such as interference and superposition, where the particle can exist in multiple states simultaneously.
However, when a measurement or observation is made, the wave function collapses, and the particle is observed as a localized entity, behaving more like a particle. This collapse occurs due to the interaction between the particle and the measuring apparatus or observer.
It's important to note that the wave function itself is not a physical wave in the traditional sense. It is a mathematical description that encodes the probabilities associated with different outcomes of measurements. The wave-particle duality arises from the intrinsic nature of quantum objects and is not solely dependent on whether they are being perceived or not.
In summary, according to quantum mechanics, particles can exhibit both wave-like and particle-like properties, and the behavior of particles is described by a wave function. The collapse of the wave function occurs upon measurement or observation, resulting in the particle being observed as a localized entity.