Quantum Mechanics and the Nature of Reality: Is the Universe Deterministic or Random?

Quantum mechanics is the branch of physics that deals with the behaviour of matter and energy on the atomic and subatomic level. With the popularity of thought experiments such as the Schrodinger’s Cat (which relates to quantum superposition), and the introduction of devices that exhibit quantum phenomena in a way that benefits humans, such as quantum computers, being associated with this branch of physics, many people seek to learn more about the compelling and ever-changing nature of quantum mechanics. One of the most interesting aspects of quantum mechanics, that will be discussed in this article, is the concept of uncertainty. This concept suggests that certain properties of subatomic particles cannot be measured with absolute precision. This has led to much debate about the nature of reality and whether the universe is deterministic or random.

Determinism is the ideology that every event has a cause and that the future is determined by the past. This implies that everything that happens is predetermined and the Universe is simply a huge clockwork, with all movements and interactions of matter and energy following predictable and precise paths.

In contrast, randomness suggests that events occur without a cause or pattern; that the universe full of chance occurrences. In essence this randomness is the ideology that the Universe is controlled by unpredictable probabilities.

How does this relate to quantum mechanics, one may ask? Well, in quantum mechanics, Heisenberg’s Uncertainty Principle states that it is impossible to know the precise position and momentum of a subatomic particle at the same time; you can know one value but it is impossible to know the exact value of the other. The product of the uncertainties of these two properties of the subatomic particle will never be 0, and in fact, according to mathematical derivation, must be greater than the reduced Planck’s constant divided by 2. As one would imagine, this principle proposes that the behaviour of these particles appears to be inherently probabilistic, considering that it is impossible to measure the properties of these subatomic particles with absolute precision. Hence, some physicists believe that the universe may be fundamentally random, with no underlying deterministic laws governing the behaviour of matter and energy in the Universe.

However, other physicists argue that this is a bold claim to make, and there are likely other hidden variables (or unknown factors) that we are yet to find, and so this supposed randomness is simply the result of our minimal progression in the field of quantum mechanics. This view is known as the hidden variable theory, and while it is a minority view amongst physics, it is definitely credible, considering that quantum mechanics was only found in the early 1900s, and so there may be many things we are yet to discover in this field, that will help to reveal a deterministic nature about the Universe.

Overall, the question of whether the Universe is deterministic or random remains a subject of intense debate among physicists and philosophers, with no determinate answer being established. However, the existence of this very debate, and our inability to come to a conclusion regarding the ideas of determinism and randomness, demonstrate humanity’s lack of understanding regarding the nature of the Universe and the fundamental laws that govern it.

By Ved Nair