You raise an important point. In science, the term "spontaneous" does not imply that an event has no cause whatsoever. Rather, it suggests that the event occurs without any apparent external influence or triggering mechanism that we currently understand or can identify.
Atomic decay, for instance, refers to the process in which an unstable atomic nucleus spontaneously transforms into a more stable configuration by emitting radiation or particles. While the precise timing and occurrence of individual atomic decays may be unpredictable, the process itself is governed by probabilistic laws and is subject to underlying physical principles.
Quantum mechanics provides a framework for understanding atomic decay. According to quantum theory, certain unstable atomic configurations have a nonzero probability of transitioning to lower energy states, and this transition occurs randomly and without any discernible cause in the classical sense. Quantum mechanics describes this randomness through concepts like wave function collapse, quantum fluctuations, and inherent probabilities associated with various outcomes.
It's crucial to emphasize that the term "spontaneous" does not imply the absence of a cause but rather reflects our current understanding and knowledge limitations. It is always possible that, with further advancements in science and technology, we may gain deeper insights into the underlying causes and mechanisms behind seemingly spontaneous events.
So, while we may not have discovered all the causes behind atomic decay or other spontaneous processes, labeling them as spontaneous is a way to acknowledge our present understanding and recognize that they occur without any evident or known external influences.