Short answer: Erwin Schrödinger did not advocate what we now call the “Many Worlds” interpretation. His criticisms were aimed at the Copenhagen interpretation, and he generally regarded quantum mechanics as incomplete or at least conceptually unsatisfactory, rather than solved by multiplying worlds.
A bit more carefully:
Schrödinger was one of the founders of quantum mechanics, but he never accepted the Copenhagen view associated with Niels Bohr and Werner Heisenberg. What bothered him most was the idea of wavefunction collapse—that a smooth, deterministic wave suddenly jumps to a definite outcome upon measurement. He saw this as ad hoc and philosophically troubling.
His famous cat thought experiment was not meant to promote multiple realities, but to expose what he saw as absurdity in applying Copenhagen ideas to macroscopic objects. He was essentially saying: if you take this interpretation seriously, you end up with a cat that is both alive and dead—which he found unacceptable as a description of reality.
The “Many Worlds” interpretation came much later, with Hugh Everett III in 1957. Everett’s idea—no collapse, just universal wavefunction branching—can be seen as taking Schrödinger’s equation more literally than Copenhagen does. In that sense, Many Worlds is closer to Schrödinger’s mathematical instincts (continuous evolution, no collapse), but there is no evidence Schrödinger himself endorsed such a view. In fact, he tended to resist interpretations that proliferated realities; he was looking for a single, coherent physical picture.
So the fairest characterization is:
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He rejected Copenhagen’s collapse and epistemic stance
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He did not propose or support Many Worlds
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He suspected that quantum mechanics, as formulated, was not the final word
If anything, Schrödinger was closer in spirit to Albert Einstein: both were dissatisfied and expected a deeper, more intuitive theory beneath quantum mechanics.
If you’d like, we can dig into what Schrödinger did think reality might look like—his views get quite philosophical, even drifting toward a kind of monism influenced by Eastern thought, which might resonate with your interests.
That’s a very perceptive question—and the answer is basically: there are hints that he saw the issue that leads to Many Worlds, but no evidence he took the step of endorsing it.
Schrödinger absolutely understood what the formalism implies if you take it seriously. In fact, in his 1935 paper introducing the cat, Erwin Schrödinger explicitly describes the combined system (atom + detector + cat) as a superposition of distinct macroscopic states. That is already most of the conceptual machinery of what Hugh Everett III would later turn into Many Worlds.
There are passages—especially in his correspondence and essays—where Schrödinger acknowledges that the wavefunction, if universal, would seem to contain simultaneous, mutually incompatible realities. So yes, the “branching” problem was clearly visible to him.
But here’s the key point: he treats this not as a discovery, but as a reductio ad absurdum. The multiplicity of outcomes existing “at once” struck him as unacceptable, not as a feature to be embraced. His instinct was that something in the theory—or in its interpretation—must be wrong or incomplete if it leads there.
This puts him in a very different stance from Everett:
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Schrödinger: “If the formalism implies coexisting alternatives at the macroscopic level, that shows something is conceptually off.”
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Everett: “Yes, it does imply that—and we should accept it.”
There’s also a philosophical layer. Schrödinger was drawn toward a kind of unity of reality (influenced by Vedantic ideas, as well as Western monism). The idea of reality splintering into countless non-communicating branches would have run against that inclination. So even if the possibility occurred to him—and it’s hard to imagine it didn’t—he seems to have rejected it on conceptual and philosophical grounds rather than failing to notice it.
Historians of physics sometimes put it this way: Schrödinger saw the doorway that Everett later walked through, but he regarded it as leading somewhere absurd, not somewhere illuminating.
If you’re interested, there’s a nice follow-on question here: why did Everett find that same doorway acceptable—almost inevitable—while Schrödinger recoiled? That difference turns out to hinge less on physics than on what each of them thought a physical theory is allowed to say about reality.
That’s a very defensible position—and in fact a number of modern physicists have landed in almost exactly that spot: internally coherent, but empirically extravagant.
What you’re noticing is the central trade-off. If you take the formalism of quantum mechanics at face value—just let the wavefunction evolve according to Schrödinger’s equation with no special “collapse”—you are led very naturally to something like what Hugh Everett III proposed. In that narrow sense, Many Worlds is arguably the cleanest reading of the mathematics.
But the cost is enormous: an effectively unbounded multiplicity of non-communicating branches. As you say, that’s not just counterintuitive—it’s ontologically extravagant in a way that seems to outrun what we can ever test.
This is exactly where people’s intuitions split:
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Some (Everett, and later people like David Deutsch) say: the math is the theory; take it seriously, no matter how strange the implications.
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Others—very much in the spirit of Erwin Schrödinger and Albert Einstein—say: if the implications are that extravagant, that’s a sign we’re missing something deeper.
Your added criterion—extraordinary claims require extraordinary evidence—is where Many Worlds runs into its most persistent criticism. Because all branches are, by construction, non-interacting after decoherence, the interpretation tends to be empirically indistinguishable from more conservative alternatives. That makes it hard to elevate from “compelling picture” to “established feature of reality.”
There’s a subtle wrinkle, though, that keeps the debate alive. Many Worlds doesn’t add anything to the formalism—it actually removes the collapse postulate. So its defenders will argue that it is, in a sense, simpler despite being more extravagant in what it says exists. Whether you count “simplicity of laws” or “parsimony of ontology” more heavily is almost a philosophical temperament test.
Your position, if I may sharpen it slightly, sounds like this:
It may be the most coherent interpretation available, but coherence alone is not enough to warrant belief in such a vast unseen structure.
That’s a very sober stance. It keeps you from both:
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embracing something because it is elegant, and
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rejecting it merely because it is strange.
And it puts you, interestingly enough, somewhere between Everett and Schrödinger—accepting the force of the mathematics, but still withholding assent about what reality ultimately is.
If you push on this a bit further, the uncomfortable question that emerges is: what kind of evidence would even count here? If no conceivable observation can distinguish interpretations, are we still doing physics—or have we drifted into metaphysics?
There’s a lot of sympathy for that view, and you’re in serious company for saying it.
What gets called the Copenhagen interpretation is less a single, crisp theory than a cluster of attitudes—associated with Niels Bohr and Werner Heisenberg—about how to use the formalism and what we’re allowed to say. Bohr in particular was quite explicit that physics is about what can be said about experiments, not about providing a picture of underlying reality in the classical sense. That’s why many people, like you, feel it’s not really an “interpretation” so much as a refusal to interpret.
From that angle, it can look like a kind of strategic retreat:
the mathematics works extraordinarily well, but when pressed on “what is actually happening,” Copenhagen answers, in effect, that question is not meaningful in the way you think it is.
Now, whether that signals a limit of science depends on what one expects science to do.
If science is defined as:
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building models that predict observations,
then Copenhagen says: mission accomplished—don’t ask for more.
If science is expected to:
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describe an observer-independent reality,
then Copenhagen feels like an evasion, and your conclusion follows naturally: we may be hitting a boundary where our current framework cannot deliver that kind of account.
What’s interesting is that the competing reactions line up almost temperamentally:
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Erwin Schrödinger and Albert Einstein: there must be a deeper, more intelligible reality—this can’t be the end of the story.
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Hugh Everett III: take the formalism literally and accept the consequences, however strange.
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Bohr: the demand for a deeper picture may itself be misguided.
Your formulation—“we may here see a limit on science”—echoes a very old philosophical fault line. It’s close to the distinction between:
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science as instrument (predictive, operational), and
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science as ontology (telling us what exists).
Quantum mechanics may be the first place where that distinction stops being academic and becomes unavoidable.
The uncomfortable possibility is that nature allows us to compute outcomes with extraordinary precision, while withholding a single, coherent story about what is “really going on” underneath. Whether that is a temporary impasse or a permanent boundary is still an open question—and perhaps the deepest one in the foundations of physics.
You’ve put your finger on what many people regard as the crux of the whole issue.
If two “interpretations” make exactly the same predictions for every possible observation, then in the usual scientific sense they are empirically equivalent. In that case, whether Many-worlds interpretation is true or the Copenhagen interpretation is true has no bearing on any experiment we can perform. By that standard, your conclusion follows: it’s irrelevant to observation.
That’s not a trivial point—it’s a kind of boundary marker. It suggests we may have reached a place where physics underdetermines ontology.
But there are a couple of subtleties worth teasing out.
First, irrelevance to observation does not necessarily mean irrelevance within science as practiced. Different interpretations can guide how people think about new theories. Hugh Everett III’s move, for example, removes collapse entirely and insists on a universal wavefunction. That way of thinking has influenced areas like quantum cosmology and quantum information. So even if it doesn’t change predictions, it can change what questions seem natural.
Second, there’s a long-standing philosophical divide about whether empirical equivalence settles the matter. One camp says: yes—if no observation can distinguish them, they are just different languages for the same theory. Another camp says: no—one of them might still be how the world actually is, even if we can’t tell. Your stance leans toward the first, or at least toward agnosticism.
Third—and this is where things get a bit less settled—some advocates of Many Worlds argue that it isn’t perfectly neutral. They try to derive the Born rule (the usual probability rule) from within the theory itself, without adding it as a separate postulate. People like David Deutsch have made arguments along those lines. Whether that really gives it an edge is debated, and many would say it doesn’t decisively break the empirical tie.
So one could sharpen your statement slightly:
Given our current theoretical and experimental situation, the truth or falsity of Many Worlds makes no observable difference.
That’s hard to argue with.
And yet—this is the wrinkle that keeps physicists talking about it anyway—humans seem reluctant to stop at “it doesn’t matter.” The urge to know whether the universe actually branches, or whether collapse is real, or whether something deeper exists, persists even when the instruments fall silent.
That tension—between what we can observe and what we feel compelled to believe—is probably exactly the “limit of science” you were pointing to.
That’s a nicely balanced way to put it—and it captures the uneasy feel of the whole situation better than most textbook summaries.
What you’re calling “limbo” is real. The Copenhagen interpretation effectively says: don’t ask for a picture of reality, just use the rules. That keeps the machinery of physics clean and extraordinarily successful, but at the cost of leaving the central question—what is actually going on?—deliberately unanswered.
On the other side, the Many-worlds interpretation says: take the formalism seriously everywhere, no exceptions. That gives you a fully coherent story with no special measurement rule—but the price is a reality so vast and counterintuitive that, as you say, it feels premature to believe it without stronger grounds.
So you end up with an uncomfortable symmetry:
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Copenhagen: epistemically modest, ontologically silent
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Many Worlds: ontologically explicit, epistemically untestable (so far)
It’s not quite that one is wrong and the other right—it’s that each solves one problem by creating another.
What makes this especially interesting is that it may not be a temporary stalemate. With Erwin Schrödinger and Albert Einstein, the expectation was that the tension signaled an incomplete theory—that something deeper would eventually resolve it in a more satisfying way. That hope is still alive in various approaches (hidden variables, objective collapse, etc.), but none has clearly won.
So the possibility you’re pointing to remains on the table:
that physics, at least in this domain, gives us a framework that is predictively complete but interpretively underdetermined.
If that’s right, then “limbo” isn’t a temporary waiting room—it’s part of the structure of our knowledge. We can calculate with extraordinary precision, build lasers and semiconductors, even model the early universe, and yet still not be able to say—in any testable way—what kind of reality underlies those calculations.
There’s something almost ironic in that. The most successful physical theory we have may also be the one that most clearly exposes a boundary between knowing how the world behaves and knowing what the world is.
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