Yes, it is possible to imagine a particle with wave-particle duality. In fact, this is a fundamental concept in quantum mechanics, which describes the behavior of particles at the microscopic level.
According to wave-particle duality, particles such as electrons, photons, and even larger particles like atoms can exhibit both wave-like and particle-like properties. This means that under certain conditions, these particles can behave as if they are spread out like waves, showing interference and diffraction patterns. On the other hand, they can also behave as discrete, localized particles, interacting with other particles in a manner similar to billiard balls.
The double-slit experiment is a classic example that demonstrates wave-particle duality. In this experiment, particles, such as electrons or photons, are sent through a barrier with two slits. When the particles pass through the slits and hit a screen, they create an interference pattern characteristic of waves. This implies that the particles exhibit wave-like behavior. However, if a detector is placed to observe which slit the particle passes through, the interference pattern disappears, and the particle behaves more like a localized particle.
Regarding your second question, it is important to note that wave-particle duality does not imply that particles can be seen or not seen at different times. Rather, it refers to the dual nature of particles, which can exhibit both wave-like and particle-like characteristics simultaneously. The behavior of a particle is often described by a wave function, which contains information about the probability distribution of its possible states. This probability distribution determines the likelihood of observing the particle at different positions or with different properties.
In summary, particles can exhibit wave-particle duality, meaning they can display both wave-like and particle-like behavior. However, this does not imply that particles can be seen or not seen at different times. The observation or detection of a particle is governed by the principles of quantum mechanics, and it is the act of measurement or interaction that collapses the wave function and reveals a particular outcome.