In quantum mechanics, the phenomenon of quantum tunneling allows particles to pass through energy barriers that would be classically forbidden. This behavior arises from the wave-like nature of particles and their associated wavefunctions.
Quantum tunneling is a probabilistic phenomenon, meaning that there is a non-zero probability for a particle to tunnel through a barrier. This probability is related to the wavefunction of the particle and the characteristics of the barrier. In quantum mechanics, any object, including macroscopic objects like a tennis ball, can be described by a wavefunction.
However, when it comes to macroscopic objects, the effects of quantum tunneling become highly unlikely and practically negligible. This is due to a phenomenon called decoherence, where macroscopic objects interact with their environment and rapidly lose their quantum properties, becoming effectively classical. The interactions with the environment cause the wavefunction to collapse into a definite state, leading to classical behavior that follows deterministic laws.
In order to observe quantum tunneling for macroscopic objects like a tennis ball, one would need to create and maintain a highly isolated and controlled environment that minimizes any interactions and disturbances from the surroundings. This is an extremely challenging task and not currently achievable on macroscopic scales.
Therefore, while quantum tunneling is a fundamental phenomenon in quantum mechanics, the probability of observing macroscopic objects, such as a tennis ball, tunneling through significant barriers is so incredibly low that it is practically considered impossible under normal conditions due to decoherence effects.