The minority theory that our whole cosmos might be the inside of a black hole — and the fresh data reviving it
In February 2025, a paper appeared in the Monthly Notices of the Royal Astronomical Society reporting a small oddity with outsized implications. Lior Shamir, a computer scientist at Kansas State University, had run an automated analysis on 263 galaxies imaged by the James Webb Space Telescope’s Advanced Deep Extragalactic Survey. JWST’s JADES survey analyzed 263 galaxies from the early universe and revealed a significant asymmetry: roughly 66% spin clockwise, while only about 33% rotate counterclockwise. The exact split, as viewed from Earth, was 158 turning one way and 105 the other.
That should not happen. A load-bearing assumption of modern cosmology is that the universe looks statistically the same in every direction. Because a core tenet of cosmology is that at sufficiently large intergalactic scales the universe’s properties should be essentially the same in all directions, we’d expect a roughly even split between clockwise- and counterclockwise-spinning galaxies anywhere we look. A lopsided sky implies something with a direction to it — a preferred axis, a built-in spin. And one of the theories that would happily accommodate a spinning cosmos is among the strangest ideas in serious physics: that everything we can see is sealed inside a black hole.
An old idea with a new hearing
Black hole cosmology is not a late-night invention. It has a paper trail going back more than half a century. Black hole cosmology was introduced by theoretical physicist Raj Kumar Pathria in a 1972 study published in the journal Nature. A mathematician named I. J. Good arrived at a similar notion independently the same year. Their entry point was a number that refuses to feel like a coincidence. What Pathria realized is that the radius of the observable universe is about the same as the Schwarzschild radius of the universe’s mass — something you’d typically only expect from a black hole. In plainer terms: if you weighed everything in the observable cosmos and asked how large a black hole that much mass would carve out, you’d get something close to the size of the observable cosmos itself.
Whether that near-match means anything is exactly the sort of question that divides physicists. It may be a deep clue; it may be a numerical accident dressed up as destiny. The relation between the Schwarzschild radius of the observable universe and the Hubble radius is noteworthy in these models but is often attributed to a mathematical coincidence or connected to the holographic principle. The honest reading is that nobody has proven the match is telling us anything at all.
For decades the idea drifted at the field’s margins. Then a handful of physicists began building actual machinery underneath it. The idea has been around for half a century, but it wasn’t taken very seriously at first; however, a series of recent studies has brought newfound attention to this mind-bending model of the cosmos. The reason a fringe notion is getting a second hearing has less to do with fashion than with frustration. The reigning framework, sometimes called the standard model of cosmology, is spectacularly successful and quietly full of holes. It works only if you accept three things nobody has directly observed: a burst of faster-than-light expansion called inflation, an invisible substance called dark matter, and a mysterious pressure called dark energy driving the cosmos apart. The black hole models promise to retire at least some of that inventory.
A bounce instead of a bang
The obvious objection to living inside a black hole is that black holes are supposed to crush everything into an infinitely dense point. If our universe were the interior of one, we’d be a speck inside a singularity, not a spacious cosmos throwing off starlight for fourteen billion years. The modern versions of the theory get around this by proposing that the crush never finishes.
The physicist who has pushed this hardest is Nikodem Popławski of the University of New Haven. His mechanism relies on a wrinkle in Einstein’s gravity called torsion — a twisting of spacetime generated by the intrinsic spin of elementary particles, formalized in what’s known as Einstein–Cartan gravity. In this theory, gravitational repulsion at supranuclear densities prevents the formation of singularities in black holes, so that the interior of every black hole becomes a new universe that expands from a nonsingular bounce. Popławski has argued the picture solves more than one puzzle at once. Torsion, he writes, provides a theoretical foundation for a scenario in which the interior of every black hole becomes a new universe, and it also appears as a remedy to several major problems of current theory of gravity and cosmology. To explain it to non-specialists he has resorted to a bottle demonstration — a “tornado in a tube,” where the upper bottle is a black hole, the linked necks are a wormhole, and the lower bottle is a fresh universe expanding on the far side.
A separate and more recent line of work reaches a similar destination by a different road. In 2025, a team led by Enrique Gaztañaga at the University of Portsmouth’s Institute of Cosmology and Gravitation published a model in Physical Review D that invokes ordinary quantum mechanics rather than exotic torsion. Their halting mechanism is the Pauli exclusion principle — the rule that two identical particles can’t occupy the same quantum state. Inside a black hole, Gaztañaga argues, the exclusion principle still applies; it prevents matter from collapsing to a point, slows the collapse, halts it at high density, and causes a bounce, avoiding the singularity altogether. On the other side of that bounce, the math produces something familiar. What emerges after the bounce is a universe very similar to ours, and the bounce naturally produces a phase of acceleration.
Gaztañaga frames the whole exercise as a matter of parsimony rather than mysticism. His calculations suggest the Big Bang was not the start of everything, but rather the outcome of a gravitational crunch or collapse that formed a very massive black hole, followed by a bounce inside it. Crucially, he insists the model doesn’t smuggle in new physics to do it. While bouncing scenarios have been proposed before, this model stands out by relying solely on known laws of physics; it avoids introducing speculative particles or forces and describes a purely gravitational collapse occurring within a black hole. And unlike a metaphysical flourish, it comes with a to-do list. The theory makes several predictions astronomers can test; for example, it predicts the universe is slightly curved — positively curved like a sphere — not exactly flat. Gaztañaga has also suggested the model should leave debris behind: relic objects such as primordial black holes or neutron stars formed before the bounce, whose discovery in the early universe would count as evidence in its favor.
This is the part worth holding onto. These are not vibes. They are claims with attached ways to be wrong, which is what separates a research program from a story.
The problem with the spinning sky
Which brings us back to Shamir’s galaxies, and to why they arrived at such a convenient moment. A universe that inherited a rotation would carry a faint fingerprint of that spin all the way down to the twirl of individual galaxies — and a spinning universe is precisely what you’d expect if the whole thing were nested inside a rotating black hole, since black holes generally spin. Shamir focuses mainly on the hypothesis that the universe is inside a gigantic black hole; because black holes naturally rotate, this could give a little spin to the entire cosmos, ultimately cascading down to tweak the twirls of individual galaxies.
Popławski, who had nothing to do with the JWST analysis, welcomed it warmly. A preferred axis in our universe, inherited from the axis of rotation of its parent black hole, might have influenced the rotation dynamics of galaxies, he told Space.com, adding that the discovery would support the theory of black holes creating new universes and that he’d be extremely excited if the findings are confirmed.
Note the conditional. It is doing enormous work, and Shamir himself is the one who put it there. His paper does not declare that we live inside a black hole. It lays out two possibilities and declines to choose. There are two primary possible explanations, Shamir has said: one is that the universe was born rotating, which agrees with theories such as black hole cosmology that the entire universe is the interior of a black hole. The other explanation is far more deflating, and it has nothing to do with the birth of the cosmos. It has to do with us.
We are not standing still. The Earth orbits the center of the Milky Way at roughly 220 kilometers per second, and that motion should, through the Doppler effect, make galaxies rotating against our own galaxy’s spin appear slightly brighter than those rotating with it. Brighter galaxies are easier to see, and easier-to-see galaxies get counted more often. Because of the Doppler shift effect, light coming from galaxies rotating opposite to the Earth’s rotation is generally brighter, which could be another explanation for why such galaxies are overrepresented in the telescope observations. On this reading the lopsided sky is not a property of the universe but a property of our vantage point — a selection effect masquerading as cosmic destiny.
The expected size of that brightness nudge is tiny; analyses put it near six thousandths of a magnitude at the Milky Way’s rotation speed. Whether so small an effect can generate so large an imbalance is genuinely unsettled, and the broader literature on galaxy-spin asymmetry has been contradictory for years, with some studies finding a signal and others finding nothing. The most sober voices in the field are urging patience rather than revelation. Writing in Scientific American, cosmologists warned that sweeping claims about the entire universe demand the highest bar of evidence, and that while cosmologists are always ready for a new and exciting revelation, we have to be extremely careful about jumping to conclusions before there’s enough evidence. The result sits at roughly 3.4 standard deviations of significance — interesting, not decisive, and a long way from the threshold physicists demand before rewriting textbooks.
One universe among many
Suppose, for a moment, that the strong version turns out to be right — that collapse, not creation from nothing, is where universes come from. The philosophical aftershock is larger than the physics.
If every black hole can bounce into a new expanding region, then black holes are not cosmic dead ends but cosmic seeds, and our universe is one leaf on a branching tree with no obvious trunk. That picture has been formalized before. In 1992 the physicist Lee Smolin proposed what he called cosmological natural selection, importing Darwin wholesale into cosmology. According to this natural selection of universes theory, black holes give birth to new universes by producing the equivalent of a Big Bang, with slightly different physical properties; this introduces variation, while the differential success in self-reproduction of universes via their black holes provides the equivalent of natural selection, leading to a Darwinian evolution of universes whose properties are fine-tuned for black hole generation. The elegance of it is that it offers a reason the constants of nature seem so improbably suited to complexity: universes good at making black holes make more offspring, and a universe good at making black holes turns out to be a universe good at making stars, chemistry, and eventually us.
Smolin’s proposal has the great virtue of being falsifiable and the great inconvenience of possibly being false. The Tufts cosmologist Alexander Vilenkin argued that black hole production could actually be boosted by tuning the constants away from their observed values, which would sink the central claim. The rate of black hole formation can be increased by increasing the value of the cosmological constant, which falsifies Smolin’s conjecture that the values of all constants of nature are adjusted to maximize black hole production. That the argument can even be conducted on those terms is the point: this is science being science, not a mystical intuition immune to disproof.
Here is where the idea earns a comparison to something astronauts describe. In 1987 the writer Frank White gave a name to the jolt of perspective people report when they see the planet from orbit. It’s called the overview effect, a term coined by White in 1987, and it refers to a shift in perspective that occurs when humans view Earth in the context of its cosmic backdrop — driving home how perfectly suited the planet is for our habitation and how unforgiving the great beyond appears. The Apollo 14 astronaut Edgar Mitchell described it as an instant global consciousness, a sudden and involuntary sense that the borders on our maps are inventions. What White found again and again was that knowing a thing and experiencing it are not the same. Astronauts told him they knew intellectually before they left that there weren’t any little dotted lines — but there is a difference between knowing intellectually and experiencing it.
Black hole cosmology, if it holds, offers the same move performed on a vastly larger stage. The overview effect shrinks nations to a rounding error. This would shrink the entire universe to one object among a lineage — not the whole of existence but a single bounce inside something bigger, with its own black holes quietly seeding descendants we will never observe. It is the overview effect turned inside out and pointed at everything at once.
The temptation now is to say that this is what we are: a daughter cosmos, one generation deep in an endless family of collapse and rebound. That is the seductive version, and it is not yet earned. What the current work actually establishes is narrower and, in its way, more impressive. A cluster of physicists has shown that our universe can be modeled as the inside of a black hole without breaking known physics, that such models can dispense with some of cosmology’s least-explained ingredients, and that they generate predictions — slight positive curvature, relic objects, a preferred axis — that telescopes can go looking for. The galaxy-spin anomaly may prove to be that axis, or it may dissolve into a Doppler artifact of our own motion through the Milky Way once more data arrives. Either outcome would be a result. The case for a universe born in collapse is not that it has been demonstrated, but that it has finally become the kind of claim the sky itself can settle.