“The currently established laws of nature are deterministic with a random element from quantum mechanics. This means the future is fixed, except for occasional quantum events that we cannot influence.”[1]

For 2500 years Western philosophers and scientists have told two recurring stories about the material foundations of the universe. The first describes a mechanistic universe governed entirely by deterministic laws of cause and effect. It is the story told by Democritus, given gravitas by Newton, and exemplified by Laplace’s demon. The second story inserts a crucial element of randomness into the mechanism. It is the story of the swerve told by Epicurus and Lucretius. It is the story of the random jumps in the evolution of the quantum wave function. In this story there is a place in the material universe for unpredictability and indeterminacy.

I want to tell a different story

In this alternative story the universe is not a deterministic clock. Nor is it mostly deterministic with occasional swerves or quantum jumps. Instead, the universe is profoundly indeterminate and probabilistic. The vast quantum plane beneath the macroscopic world consists entirely of infinite random interactions. In the aggregate these interactions conform to probabilities and even create the appearance of determinacy. But determinacy in this story is not fundamental. It is an emergent generalization in a probabilistic universe.

The story of indivisible quantum theory

This alternative story is suggested by the recent work of Jacob Barandes on indivisible quantum theory. I won’t claim a deep understanding of the mathematics, but after reading his articles and listening to hours of discussion among Barandes and prominent philosophers of physics,[2] I begin to see why his theory has earned so much attention.

• The theory restates the fundamentals of quantum mechanics using the mathematics of stochastic probability, mathematics that was not available to the founders of quantum theory in the early 20^th century.
• It reproduces the key results of quantum mechanics, relying not on complex, imaginary numbers and abstract Hilbert space, but on general configuration space that maps more directly to classical mechanics and objective physical states.
• The theory does not rely on a deterministic wave function with complex number weightings that transform into real-world probabilities. It does not require state vector reduction or wave function collapse to calculate probabilities.
• Instead, the theory assumes that the quantum world always evolves stochastically with inherently indeterminate random variables. The physical state of the universe unfolds probabilistically, with the probabilities emerging from the initial conditions and evolving stochastically over time.
• The probabilities do not determine the unique behavior of particles, fields, or perhaps even systems. Instead, the inherent randomness of the quantum world conforms only in the aggregate to the evolving probabilities, creating the appearance of determinacy in the macro world.
• Importantly, the theory is non-Markovian and indivisible. The quantum world evolves as an undivided whole based on physical memory of its history, including the initial conditions and subsequent configurations. The configuration of the universe at any given time does not contain all the information necessary to predict its configuration in the next moment, instead requiring additional information from its own history.

Indivisible quantum theory is a radical reconstruction of quantum mechanics. It replaces much of the abstract and complex number mathematics with a straightforward description of dynamically probabilistic evolution. It does not interleave deterministic time evolution with mysteriously random state vector reduction. The theory presents a simpler picture of consistently indeterminate and probabilistic time evolution throughout the history of the universe.

The entrenchment of the clockwork universe

If the theory is correct, physicists and philosophers may have to rewrite or abandon the long-told narrative in which the vast lake of reality is deterministically logical, obedient to the ironclad laws of nature, with steely predictability disturbed only occasionally by rogue quantum waves. Natural scientists have long been committed to that deterministic vision of the universe. Democritus described a world of tiny particles whose motion drives the evolution of the universe. Newton depicted a reliable clock ticking along according to fixed laws of motion. Laplace gave the world his demonic thought experiment, imagining that an omniscient entity with complete knowledge of the physical state of the world could predict the future exactly. The story of the mechanistic universe has been retold again and again until it became the prevailing opinion of almost every Western scientific mind in the nineteenth century.

In the following century the emergence of quantum mechanics challenged that narrative, but did not displace it. Instead, it revived an ancient twist, the random swerve. In Epicurean and Lucretian materialism the motions of tiny particles govern a largely mechanistic world. But the tiny particles occasionally swerve arbitrarily and without cause. The swerve introduces an element of randomness, making the world less predictable and deterministic. Quantum theory gave this story a new scientific legitimacy in the form of random wave function collapse, forcing scientists to incorporate indeterminacy into their fundamental theory of the universe.

From the beginning, however, many scientists and philosophers only reluctantly accepted the central role of probability and randomness. Some saw quantum collapse as awkward and ugly, something to eliminate in the next great theory of the universe. Starting with Einstein’s declaration that “God does not play dice,” one hundred years of physics have seen repeated efforts to explain away the indeterminate component of quantum theory.

The standard Copenhagen interpretation of quantum mechanics never fully affirmed the physical reality of wave function collapse. It accepts the practical need for the Born Rule and quantum reduction as an epistemological tool, not as a description of nature.

David Bohm’s pilot wave theory does not accept quantum collapse at all. Instead, it provides a missing variable that makes quantum reduction unnecessary. The theory posits the existence of pilot waves that guide particles along continuous, deterministic paths. The wave function never collapses and there is no quantum jump, only a continually evolving quantum state as defined by the Schrödinger equation.

Hugh Everett’s “many-worlds” theory goes further. Rather than accept indeterminacy as a permanent characteristic of the universe, the theory imagines an infinite number of alternate worlds, all of which are deterministic. Our world only appears indeterminate because we cannot see the other worlds in which all the possibilities play out in a completely deterministic manner.

Even among theorists who accept quantum collapse as a physical thing, random indeterminacy is often viewed as an Epicurean swerve, an occasional random event that periodically disrupts the otherwise deterministic evolution of the universe.

After a century of quantum mechanics, it may be fair to say that many scientists still support a deterministic narrative close to the vision of Democritus and Newton, with only minor exceptions for quantum indeterminacy. Bohmian and Everettian theorists tell a story in which the universe is entirely deterministic, with quantum mechanics having only the appearance, not the reality, of indeterminacy. 

Can physics accept a thoroughly probabilistic universe?

Indivisible quantum theory, however, has ramifications that thoroughly undermine these often-told narratives.

Instead of a largely deterministic world with an occasional random event, it describes a ubiquitously indeterminate world that conforms to expected outcomes only due to probabilities playing out over an infinitely large number of random interactions.

Instead of a debate about the physical reality of the wave function, there is no need for a wave function at all. The wave function is an optional calculation tool that provides a convenient proxy for predicting the behavior of an indeterminate quantum world.

Because the wave function is not intrinsically necessary, indivisible quantum theory has no need to explain away wave function collapse. The universe does not need a pilot wave or any missing variable to guide particles along continuous, deterministic paths. Nor does it need a universal wave function that never collapses but splits into many worlds, each following its own deterministic trajectory.

To the contrary, if indivisible quantum theory is correct, the universe has no continuous, deterministic path. There is only the appearance of determinism. The continuous and deterministic evolution of the wave function is not a model of physical reality, but instead represents an emergent generalization describing the aggregate results of an ocean of indeterminate interaction.

None of this will be easy for physicists and philosophers to accept. But if the theory is correct, this may be our new best description of the physical universe.

The future is not fixed

Perhaps the most important philosophical implication of the new theory is the obvious inference that the future is not fixed at all. The evolution of the universe is probabilistic, and the probabilities play out in the aggregate. They do not govern unique quantum interactions, and perhaps not unique interactions of any entity or system susceptible to chance.

The probabilities themselves also are not fixed. The initial conditions of the universe may set probabilities that become the “laws” of nature as we perceive them, and the influence of initial probabilities may be overwhelming, but the universe evolves stochastically and indivisibly, so the probabilities have the potential to change based on the subsequent history of the universe.

So not only is the future not fixed at the micro scale, the probabilities playing out at the macro scale also are not completely static. The universe is probabilistic at both the smallest and the largest scales.

In a stochastic universe even the smallest quantum entity or subsystem has the potential to do something unexpected which might influence the probabilistic trajectory of the universe. The influence of a single action may be almost entirely insignificant. But if the path of the universe is set probabilistically by all those tiny interactions taken together, then this is a universe in which every entity and subsystem may matter.

That is a universe that matters to me. 

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[1] Hossenfelder (2022), p. 125.

[2] See video discussions with Tim Maudlin, David Albert, and Sean Carroll in Erhardt (2026, February 15), Erhardt (2026, June 29), and Carroll (2025, July 28).