The behavior of electrons and other particles at the quantum level is described by wave-particle duality, which means that they can exhibit characteristics of both particles and waves. In the double-slit experiment, for example, electrons can behave as waves and exhibit an interference pattern when passing through two slits. However, when we observe or measure the electrons, their wave-like behavior collapses, and they behave more like particles, displaying a definite position.
This collapse of the wave function, often referred to as wave function collapse or quantum collapse, occurs due to the interaction between the electron and the measuring apparatus. When we observe or measure the electron, we typically use photons (particles of light) to detect its position or other properties. This interaction with photons affects the electron's state and causes the wave function to "collapse" into a specific position or value.
The exact mechanisms behind wave function collapse are still the subject of debate and interpretation in quantum mechanics. One interpretation is the Copenhagen interpretation, which suggests that the act of measurement or observation inherently disturbs the system and forces it into a particular state. Another interpretation is the many-worlds interpretation, which proposes that all possible outcomes of a quantum event exist simultaneously in different branches of reality, and measurement simply selects one of those outcomes, causing the observer to perceive a definite result.
It is important to note that the act of observation or measurement doesn't necessarily require a conscious observer. Any interaction that gathers information about the particle's properties, such as photons bouncing off it, can cause the collapse of the wave function.
In summary, the act of observing or measuring an electron disrupts its wave-like behavior and collapses its wave function, causing it to behave more like a particle with a definite position. The precise reasons for this collapse are still a topic of scientific inquiry and various interpretations exist within the field of quantum mechanics.