The idea that our universe is the inside a black hole It sounds like science fiction, but it's been around in theoretical physics for decades and has resurfaced with force after observations by the James Webb Space Telescope. What if our reality is the offspring of another, older cosmos, a sort of cosmic onion with layers that are born inside giant black holes?
In parallel, New measurements have found a puzzling patternIn images of the early universe, many galaxies appear to spin mostly in the same direction. Such a bias challenges a pillar of the standard cosmological model and opens up two explanatory avenues: either the universe was born rotating (perhaps because it emerged inside a rotating black hole), or we are seeing a selection effect due to the brightness and motion of our own galaxy. Here, we calmly and data-drivenly unravel the rationale behind this intriguing hypothesis.
From the Big Bang to the 'seed of the universe' hypothesis
About 13.800 million years ago, Space-time expanded abruptly in what we call the Big BangMany physicists argue that it makes no sense to speak of a before, because time, as we understand it, begins at that very instant. Still, other researchers have explored whether a previous stage could have existed, describing the origin as the materialization of a cosmic seed: a finite, tiny, and extremely dense package of matter and energy capable of triggering the creation of all the particles and structures we observe today.
This seed would be unimaginably small, billions of times smaller than any particle detected in the laboratory, and yet real enough to illuminate galaxies, stars, and planets. The comparison to a plant seed is not accidental: an essential nucleus enveloped in a kind of protective covering that preserves its contents until the moment of germination.
What happens inside a black hole
Nature offers a scenario that fits surprisingly well with that image: the inside of a black hole. When a very massive star collapses on itselfGravity compresses matter to brutally high temperatures (on the order of tens of billions of degrees) and smashes atoms and electrons. If the crushed nucleus exceeds a critical mass threshold, there is no known force that can stop its fall: a black hole is born.
The border that delimits the inside from the outside is known as the event horizon: From there, not even light can escapeThere are different scales of black holes. Stellar-mass ones, with between a few and a few tens of solar masses, are distributed throughout the Milky Way. At the other extreme are the supermassive, which accumulate from hundreds of thousands to billions of suns and settle in the centers of most galaxies, including ours.
In between, the community has searched for years for the elusive intermediate-mass black holes (about 100 to more than 10.000 suns). In 2019, a merger detected by LIGO (GW190521) yielded the strongest candidate to date, with a remnant of 142 solar massesThese observational pieces map a cosmic zoo whose extreme physics we are still learning to read.
From singularity to 'big boat': Poplawski's proposal
If one extends Einstein's equations into the interior of a black hole, a singularity appears: a point of size zero and infinite densityPhysicists aren't keen on infinities, because they often indicate that a theory has reached its limits. Therefore, some have proposed that, instead of a singularity, a real, compact, and finite seed forms within it, with a formidable but limited density.
Physicist Nikodem Poplawski of the University of New Haven has argued that The rotation of black holes completely changes the scriptIn his view, black holes spin very fast (close to the speed of light), and this spin leaves a mark space-time torsion. Falling matter is not compressed indefinitely: it becomes compact and twisted, like a fully compressed springWhen the compression can no longer increase, the system rebounds and generates a new space-time within itself: a big bounce, a Big Bang from within.
In that reading, a black hole acts as a one-way door between two universesThe analogy of two trees sharing a root illustrates this well: there is a deep connection between the two trunks (universes), but each grows with its own identity. Thus, our cosmos could have been gestated inside a black hole of an older parent universe. And even today, despite accelerated expansion, we could continue living within the horizon of that primordial black hole, because the horizon is a geometric boundary that can encompass a growing internal space-time.
The James Webb's clues: a puzzling galactic rotation
The recent observational push has come from James Webb. An analysis of 263 very distant galaxies, obtained within the JADES (Advanced Deep Extragalactic Survey) program, found that about 60% appeared to spin clockwise, compared to 40% counterclockwise. The difference is so clear that, in the words of the researchers, It is obvious even without technical training when inspecting images.
Another team, in the ADES (Advanced Deep Extragalactic Survey) program, published an even more striking result on February 9, 2025: in their sample, More than two-thirds of the galaxies analyzed showed the same direction of rotationBoth findings strain a premise of the standard cosmological model (ΛCDM), which assumes that the universe is homogeneous and isotropic on a large scale, that is, that there should be no preferred direction.
These works, disseminated in forums such as Monthly Notices of the Royal Astronomical Society and commented on in specialized media, They put the idea of ​​a rotating universe back on the table.If the cosmos has a preferred axis, it may have inherited it from a progenitor black hole. Researchers like Lior Shamir of Kansas State University have voiced this possibility in articles and interviews with media outlets such as Space.com and Newsweek.
Two explanations in the running: rotating cosmos or brightness bias
The first hypothesis states that the universe was born with a spinThis notion is closely related to the so-called black hole cosmology (or Schwarzschild cosmology), originally proposed in the 70s by Raj Kumar Pathria and later refined. In such a scheme, a universe emerging from within a rotating black hole could retain a preferred axis; This fossil axis would influence the dynamics of matter and, by extension, in the statistical rotation of galaxies.
The second explanation appeals to observation in motion: our system is not still. The Earth orbits the center of the Milky Way, and this shift introduces a subtle Doppler effect. Galaxies whose spin, as seen from here, opposes galactic motion might appear slightly brighter, so would be overrepresented in the sample when we look too far ahead. If this bias has been underestimated, it would be time to recalibrate some fundamental metrics.
That recalibration would not be minor. It would affect the way we infer cosmic distances. from brightness and could alleviate other open tensions in cosmology, such as discrepancies in the expansion rate of the universe (the famous Hubble tension) or the discovery of galaxies so developed at such early ages that they seem to defy standard chronology. Correcting the expected brightness, if necessary, could move the needle on several fronts.
Cosmic Russian Dolls: Black Holes as Matrices of Universes
If we accept the scenario of Poplawski and company, black holes would not be stellar tombs but, in a certain sense, cosmic birthersWhat our intuition interprets as the end of matter would be the beginning of another space-time. That is why the idea has been described as a Russian doll set: Each black hole would contain a complete universe inside it, and in turn in that universe more black holes would be born with the potential to engender other cosmoses.
In this view, the so-called singularities are reinterpreted as transition bridges Between a collapsing cosmos and one emerging. Proposals based on torsion gravity or quantum bounces circumvent infinity and offer a physical mechanism for this great bounce. As Poplawski summarized in interviews with the media, black holes do not annihilate matter: they recycle it into a new beginning.
The philosophical implications are intense. Inside a black hole, space and time do not behave as they do outside. of the horizon; our past and future would be concepts relative to the internal framework. And the structure of the whole would be hierarchical: a possibly infinite network of universes connected by these gravitational births. All this without repealing the standard model, but complementing it where it falters: the origin of time, the initial singularity, dark matter or the long-sought connection between general relativity and quantum mechanics.
Black holes, from the cosmic laboratory to the historical photograph
The observational deployment of the last decade has been spectacular. In 2015, LIGO detected for the first time gravitational waves: wrinkles in the fabric of space-time predicted by Einstein a century earlier. Event GW150914 showed two spiraling black holes eventually merging. Since then, catalogs have multiplied with dozens of additional detections.
In 2019, another symbolic milestone was reached: the Event Horizon Telescope (EHT). published the first image of a black hole, the colossus M87*, with more than six billion solar masses and some 55 million light-years away. The dark silhouette surrounded by a hot ring of orbiting matter became an icon of our scientific age.
The radiation we see around these objects comes from the gas that surrounds them: The enormous forces near the horizon heat matter to millions of degrees, emitting everything from radio waves to X-rays and gamma rays. Some of this gas is ejected in the form of relativistic jets that can extend hundreds of thousands of light-years and shape the evolution of their host galaxies.
For their part, the Hubble, Chandra, Swift, NuSTAR and NICER space telescopes, among other instruments, They continue to monitor black holes and their environments in multiple wavelengths to delve deeper into their role in the architecture of the universe. This entire technical arsenal, in tandem with the James Webb Astrophysics, is opening a window to the remote eras when the first galaxies were forged.
Are we in? Evidence, limits, and what's left to know
The million dollar question is inevitable: Do we live inside a black hole? For now, the honest answer is that we have no conclusive evidence. Observations of the direction of spin suggest an intriguing pattern, but the authors themselves insist that larger samples, independent methodologies, and exquisite controls for bias and selection are needed. The asymmetry may point to a cosmic axis or reflect instrumental and kinematic effects.
In parallel, the theory must refine its predictions. The equations of general relativity in extreme regimes They remain a slippery slope, and extensions with twisting or quantum bounces will have to be filtered through observation. If black hole cosmology is part of the answer, it should leave measurable traces in the background radiation, in the distribution of large structures, or in the statistics of galactic rotations that we can falsify with future data.
It is also worth remembering that Black hole cosmology is not intended to replace the Standard Model, but rather to fill in the gaps. The LCDM framework has demonstrated outstanding predictive power, and any competing or complementary theory must replicate its successes while better explaining its weaknesses. For now, the idea of ​​a universe born inside a black hole serves as a fertile working hypothesis, motivating more precise observations and calculations.
Key dates and pieces of the puzzle
To put everything into context, it's helpful to keep a few milestones in mind. In 2014, informative explanations were already circulating. which described how a rotating black hole could form the seed of a new universe and how, under certain conditions, our cosmos would be the offspring of another. Then, in 2020, comprehensive reviews of the physics of black holes and their types were published, with an emphasis on LIGO discoveries and the EHT image of M87*.
In 2025, the teams working with the James Webb They brought the controversy over preferential spin in samples of distant galaxies (JADES and ADES) to the table, with percentages ranging from 60/40 to more than two-thirds in the same direction. Publications in the Monthly Notices of the Royal Astronomical Society and notes from Kansas State University consolidated the debate, amplified by media outlets such as Space.com, Newsweek, and Interesting Engineering.
The dialogue between theory and observation, as is usual in science, will mark the coming yearsIf the spin asymmetry holds up under scrutiny and isn't explained solely by brightness or selection biases, we'll have a strong clue in favor of a universe that somehow resembles the spin of its progenitor. If not, we'll have fine-tuned our tools and calibrations, which is no small feat in a field where every tiny correction changes the cosmic map.
The beauty of this hypothesis is how it forces us to look deeper.Perhaps black holes aren't the end of the road, but cosmic cradles. Perhaps our universe has a mother, and she, in turn, is gestating offspring in the cores of her black holes. And although we can't quite lift the curtain yet, the findings of the James Webb, Gravitational waves and images of the event horizon are leaving us with breadcrumbs that point to a cosmos that is stranger, bolder, and more interconnected than we suspected.
