The concept of quantum tunneling, where a particle can penetrate through a potential barrier despite lacking the classical energy to overcome it, is indeed a fascinating aspect of quantum mechanics. While it is true that quantum tunneling has been experimentally observed and verified for particles such as electrons and atoms, the question of whether macroscopic objects like tennis balls can tunnel is a topic of theoretical speculation rather than an established phenomenon.
When physicists discuss the possibility of quantum tunneling for macroscopic objects, such as tennis balls, they typically do so within the framework of thought experiments and theoretical models. These discussions explore the boundaries and implications of quantum mechanics and often involve extrapolating from the well-established principles governing the behavior of microscopic particles.
In quantum mechanics, the probabilities associated with various outcomes are derived from the mathematical formalism of quantum theory, which involves solving the Schrödinger equation or employing other equivalent mathematical formulations. The probabilities are not solely derived from statistical distributions of observations; instead, they arise from the wave nature of quantum particles and the principles of superposition and interference.
Regarding the claim of non-zero probability for quantum tunneling of macroscopic objects, it is important to note that such discussions often involve hypothetical scenarios where the macroscopic object is treated as a quantum system. In these scenarios, the wave function of the object would be considered and the potential barriers it encounters could be theoretically analyzed. However, it is crucial to distinguish between theoretical discussions and experimental observations. To date, there has been no experimental evidence demonstrating quantum tunneling of macroscopic objects like tennis balls.
In summary, the consideration of non-zero probabilities for quantum tunneling of macroscopic objects, while intriguing, is primarily a topic of theoretical exploration and speculation. Theoretical models and thought experiments can be employed to investigate the boundaries and implications of quantum mechanics, even though such phenomena have not been directly observed in experiments involving macroscopic objects.