A Universe That Shouldn't Exist
In early 2025, MIT physicist Ying Zhao stared at formulas on her blackboard, deep in thought. The question seemed absurdly simple: how many states can a closed universe — like a sphere with no boundary — have?
Her answer: 1.
Not 10^80 (the number of atoms in the observable universe), not infinity — just one. The entire universe, including every black hole, star, planet, and life form, could only exist in one quantum state.
That means such a universe couldn't store even a single bit. You couldn't distinguish "0" from "1", record anything, or have any structure. It would be emptier than a blank hard drive — which at least has a "blank" state distinguishable from others.
The problem: we may live in a closed universe.
"There are infinitely many states on my desk," says Edgar Shaghoulian, a physicist at UC Santa Cruz. Describing a single dust mote requires astronomical information. Yet the formula says none of this should exist.
This isn't a fringe prediction. It comes from the holographic principle — one of physics' most trusted tools, which helped resolve the black hole information paradox that stumped physicists for half a century.
From Black Holes to the Cosmos
In 1997, Juan Maldacena of the Institute for Advanced Study showed that in certain universes, everything happening inside a 3D bulk (with gravity, black holes, particle collisions) is completely encoded on its 2D boundary — like a can whose surface fully describes its interior. The 2D "shadow" isn't an approximation but an exactly equivalent description. This is the holographic principle.
In 2019, Maldacena and three colleagues used it to propose the "island formula", explaining how black holes preserve information that falls in — a near-50-year-old puzzle solved.
But black holes were just a warm-up. "Black holes are a good testing ground, but the real battlefield is quantum cosmology," says Henry Maxfield of Stanford.
The One-Dimensional Hilbert Space
In quantum mechanics, a system's possible states live in a mathematical structure called Hilbert space. A classical bit has a 2-dimensional Hilbert space; an electron in a hydrogen atom has an infinite-dimensional one. Most real quantum systems are infinite-dimensional and can encode infinite information.
So a universe's Hilbert space should be infinite-dimensional, right? But Maldacena applied the island formula to a closed universe and found its Hilbert space is only one-dimensional — a single state, with no information, complexity, or structure.
"I was extremely shocked," Zhao recalls of first seeing the result. "I tried to argue with him." She spent years hunting for a flaw. But physicists studied closed universes of different kinds — with black holes, with "baby universe" bubbles — and the Hilbert space always collapsed to one dimension.
"Eventually we believed it," Zhao says.
The Clue from Topological Field Theory
Topological field theories describe the shape and connectivity of space (why a donut and a coffee cup are topologically equivalent). Oddly, their Hilbert spaces can also be one-dimensional. But if you cut the space into regions, everything changes: the boundaries between regions introduce new degrees of freedom, and you need a much larger Hilbert space.
"The rules of the game change," says Shaghoulian. Perhaps a closed universe needs to be "cut" to recover its complexity.
But how? A closed universe has no natural boundary.
The Observer: The Universe's "Cutting Knife"
In 2024, Zhao joined MIT and began working with Daniel Harlow and Mykhaylo Usatyuk. Their key insight: quantum mechanics itself demands such a cut.
Every quantum experiment draws a fundamental line between observer and observed system — a macroscopic, classical observer (a scientist and her instruments) versus a microscopic quantum system (an atom).
The team realized this split acts like cutting the space in a topological field theory. The observer introduces a new boundary — not the universe's boundary, but the boundary of the observer itself.
Put a classical observer inside a closed universe, and all the vanished complexity comes back. In early 2025, the MIT team published their paper; nearly simultaneously, another independent group proposed a similar idea, and more physicists connected it to earlier work.
"View from Somewhere": A Paradigm Shift
If correct, this marks a fundamental shift. Physics has traditionally pursued a "view from nowhere" — a fully objective description of the universe independent of any observer, with observers emerging later from that world.
The MIT work suggests such a view may not exist at all. Perhaps all we can have is a "view from somewhere" — each observer's own perspective.
This isn't relativism: physical laws don't change with viewpoint. But the description of the universe's state may be intrinsically observer-dependent.
What Would Feynman Say?
A bold analogy: imagine a computer with no screen. Its CPU runs, its disk reads and writes — but there's no way to "see" the data. From outside (measuring power draw or temperature), you can't tell whether it's running a complex 3D game or showing a blank screen. Its externally accessible state space is tiny.
But if you could enter the computer — become its user, see every pixel — a world of richness suddenly appears.
The observer is the universe's "user interface". Without observers, the universe's "internal states" can't be distinguished. With observers, infinite complexity emerges.
AI: New Observers?
A troubling corollary in the age of AI: what kind of observer creates complexity? Must it be a biological observer like us?
In Zhao's calculations, the observer is modeled as a classical macroscopic system. Does a thermometer count? A camera? A neural network?
If any system that can distinguish states qualifies, then AI — systems that sense, classify, and remember — might also be observers, "unlocking" part of the universe's complexity in their own way.
This is pure speculation. Zhao and colleagues stress they don't know the full answer; the paradox might eventually dissolve as a misunderstanding. But "view from somewhere" is, for now, the most promising direction.
The Universe Needs to Be Seen
Imagine a painting. Is it still a painting when no one looks at it? Physically, the paint molecules don't vanish. But informationally — if no observer distinguishes "this painting" from "that one", feels its beauty, understands its composition, remembers its colors — the painting's information content is, in a deep sense, nearly zero.
The universe may be the same. Matter doesn't disappear; energy doesn't disappear. Meaning disappears. Without observers to distinguish "this state" from "that state", the universe's infinite possibilities collapse into an indescribable single point.
Perhaps Feynman was right: the universe is not only stranger than we imagine, but stranger than we can imagine. It may need not just matter and energy to exist, but to be seen to become itself.
And on this planet, for the first time in 13.8 billion years of cosmic history, we are creating new "eyes" to see it — not biological, but silicon-based, electronic, made of mathematics. Perhaps they are opening yet another layer of the universe's complexity.
The universe needs to be seen. And we — carbon-based and silicon-based — are learning how to see it better.
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*References:*
- *Zhao, Harlow & Usatyuk (2025), "Observers and Islands in Closed Universes"*
- *Quanta Magazine, "Cosmic Paradox Reveals the Awful Consequence of an Observer-Free Universe" (Nov 19, 2025)*
- *Maldacena et al. (2019), "Islands in de Sitter space"*