Quantum mechanics is one of the most successful scientific theories ever constructed. Its empirical adequacy is extraordinary, its predictive power unmatched, and its technological consequences—semiconductors, lasers, MRI, atomic clocks—are so deeply woven into contemporary life that the theory has become infrastructural. By any ordinary scientific standard, it is a triumph.
And yet, physicists remain dissatisfied with it.
This dissatisfaction is not a marginal sentiment, nor a crankish minority position. It is voiced by Nobel laureates and graduate students alike, and it recurs with remarkable persistence across generations. Quantum mechanics, we are told, is incomplete, unsatisfactory, conceptually troubling, or in need of interpretation. It works—but something about it is said to fail to tell us what is really going on.
This series begins from a simple observation: that dissatisfaction does not arise from the physics.
It arises from something else entirely.
1. Success Without Satisfaction
There is no serious dispute about the empirical success of quantum mechanics. Competing theories have not outperformed it. No experiment has forced its abandonment. On the contrary, its formal apparatus has survived every empirical challenge placed before it, often with astonishing precision.
What troubles physicists, then, cannot be its predictive failures—because there are none. Nor can it be internal inconsistency in the mathematical formalism—because the formalism is exceptionally robust.
The unease appears only when a different question is asked:
But what does quantum mechanics say about reality?
This question marks a decisive shift. It is the moment at which physics quietly stops, and something else begins.
2. From Formalism to World-Picture
Quantum mechanics, as a physical theory, is a formal system constrained by empirical adequacy. It provides rules for generating probabilities of outcomes under specified experimental conditions. It tells us what to expect when certain procedures are carried out, and it does so with extraordinary reliability.
But nowhere in this description does the theory demand that it provide a picture of reality itself.
The move from formal success to ontological dissatisfaction occurs only when physicists begin to treat the theory as if it ought to answer questions of the following kind:
What entities really exist?
Are there particles, waves, fields, branches, or hidden variables?
Is the world fundamentally deterministic or indeterministic?
Does the universe split, collapse, or evolve unitarily?
These are not questions that can be settled by experiment—not because experiments are difficult or expensive, but because no conceivable experiment distinguishes the competing answers. Interpretations of quantum mechanics differ precisely in ways that make no empirical difference.
At this point, physics has exhausted its authority.
What remains is philosophy.
3. The Unacknowledged Transition
Curiously, this transition is almost never acknowledged as such. Physicists routinely insist that they are just doing physics, even while arguing passionately about the nature of reality, the meaning of existence, or the structure of the universe at its most fundamental level.
This insistence is often accompanied by a professed contempt for philosophy, typically on the grounds that philosophy does not test its claims experimentally. But this objection misses its target entirely.
Philosophy is not an experimental discipline. It does not compete with physics by proposing rival predictions. Its task is different: to make explicit the conceptual commitments that are already in play, whether they are acknowledged or not.
When physicists debate the reality of wavefunctions, the existence of many worlds, or the status of observers, they are not conducting experiments. They are articulating—often implicitly—ontological commitments. The fact that these commitments are untested does not make them optional; it merely makes them invisible.
The irony is sharp: physicists reject philosophy for failing to do what physics does, while unknowingly relying on philosophical assumptions that physics itself cannot test.
4. “Shut Up and Calculate”
The slogan “shut up and calculate” is sometimes offered as a way out of this predicament. If ontological questions are troubling, the suggestion goes, perhaps they should simply be ignored.
But this posture does not eliminate ontology. It merely drives it underground.
Even the decision to treat quantum mechanics as a mere calculating device presupposes a view about what kinds of questions are legitimate, what counts as explanation, and what it means for a theory to be about the world at all. These are not physical commitments; they are philosophical ones.
Refusing to articulate them does not make them disappear. It ensures only that they remain unexamined, inherited, and resistant to critique.
5. The Real Source of the Trouble
The persistent dissatisfaction with quantum mechanics is therefore not a signal that the theory has failed. It is a signal that physicists are uneasy with the ontological expectations they bring to it.
Quantum mechanics does not violate experimental constraints. It violates habits of thought formed under earlier physical theories—habits that smuggle in assumptions about determinism, separability, and observer-independence without acknowledging them as assumptions.
What is experienced as a crisis in quantum foundations is, more accurately, a crisis of unacknowledged philosophy.
Quantum mechanics works. What troubles us is not the theory, but the belief that a physical theory must also deliver a single, unambiguous picture of reality itself.
6. Where This Series Is Going
The posts that follow will examine this situation more closely: how physicists come to make ontological claims without recognising them as such; how the concept of “reality” functions as an unmarked term in foundational debates; and why contempt for philosophy often results in particularly poor metaphysics.
The aim is not to offer yet another interpretation of quantum mechanics. It is to clarify what kind of dissatisfaction is actually at work—and why no amount of new physics will resolve a problem that is not, at bottom, a physical one.
Quantum mechanics does not fail to describe reality.
It exposes our confusion about what we think “reality” must be.
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