Question

I know that it is certainly possible for the universe to be stochastic at one level, but deterministic at a higher level. For example, I have read that while quantum mechanics is a stochastic theory, at the scale of molecules and higher, the stochasticity "washes out", and the phenomenon becomes deterministic. But what about the reverse?

Answer 1

In quantum mechanics, behavior at the microscopic level is probabilistic, but becomes deterministic at larger scales. This can be explained by the concept of wave-particle duality, where particles exhibit both wave-like and particle-like behavior. An example of this is the double-slit experiment.

Step-by-step explanation:

In quantum mechanics, the behavior of particles at the microscopic level is described probabilistically, making it a stochastic theory. However, at larger scales, such as molecules and higher, the stochasticity is said to 'wash out' and the phenomenon becomes deterministic.

To understand this, we can consider the concept of wave-particle duality. At the quantum level, particles exhibit both wave-like and particle-like behavior. This duality means that the behavior of particles can be described by both deterministic classical mechanics and probabilistic quantum mechanics.

An example of this is the double-slit experiment, where individual particles, such as electrons, exhibit wave-like behavior when passing through two slits. However, when many particles are involved, their collective behavior can be accurately described by the deterministic laws of classical mechanics.