Laasya Daasari

Determinism vs. Probability: An Argument Between Physics and Philosophy

Started June 2, 2023

Abstract or project description

Is the universe deterministic or probabilistic? What can different interpretations of Bell’s theorem say about whether our classical and quantum realities are ruled by deterministic or probabilistic laws?

From Greek philosophers all the way to present day physicists, the “nature of the universe” debate has morphed from a philosophical discussion to a scientific one, highlighting the clear differences between quantum and classical mechanics. The recent developments of quantum mechanics have expanded our philosophical understanding of how the universe works. However, aspects of quantum physics itself, such as the collapsing of a wave function or what qualifies as a measurement are still being questioned due to our incomplete understanding of them, leading physicists to theorize quantum interpretations that predict what may be going on behind the scenes. Bell’s theorem helps answer these uncertainties in quantum mechanics by ruling out local hidden variable theories, which in turn definitively shows that the universe cannot be governed by classical mechanics, because classical mechanics is a local hidden variable theory. By recognizing the universe behaves quantum mechanically, this paper concludes that the answer to this debate leans towards being probabilistic rather than deterministic. This conclusion is derived from the conflicting concepts of locality versus quantum mechanics and is supported by most quantum interpretations. Quantum mechanics does not allow for a local description of the universe. Overall, clearly understanding the processes and rules followed at the quantum level will lead to a better awareness of how our universe as a whole truly functions, especially on a quantum scale.