The behavior of quantum particles is indeed quite different from the classical objects we encounter in our everyday lives. The phenomenon you are referring to is known as quantum fluctuations, where particles can seemingly appear and disappear in a seemingly random manner.
Quantum fluctuations are a consequence of Heisenberg's uncertainty principle, which states that certain pairs of physical properties, such as position and momentum, cannot be precisely known simultaneously. This principle leads to inherent uncertainties in the behavior of quantum particles. According to quantum mechanics, particles can momentarily borrow energy from the vacuum of space, resulting in the creation and annihilation of particle-antiparticle pairs.
However, it's important to note that these fluctuations are not due to the particles simply moving too fast for us to detect. Quantum fluctuations occur even in situations where the particles are not moving at all. These fluctuations are an inherent feature of quantum mechanics and have been experimentally observed in various contexts.
Furthermore, the effects of quantum fluctuations are not limited to the subatomic realm. They have tangible consequences on macroscopic scales as well. For instance, the Casimir effect, where two uncharged metal plates are drawn together by quantum fluctuations, is a well-known macroscopic manifestation of quantum behavior.
In summary, the phenomenon of quantum fluctuations is a genuine characteristic of the quantum world and cannot be solely attributed to particles moving too fast for detection. It is an inherent consequence of the probabilistic nature of quantum mechanics and has been experimentally confirmed in various contexts.