I. Five Percent
According to the standard cosmological ΛCDM model (Lambda Cold Dark Matter — a model describing the composition and evolution of the Universe), confirmed by data from the ESA Planck mission, visible matter — the atoms that make up stars, planets, bodies, books, instruments, and everything humans have ever measured — accounts for roughly 5% of the mass-energy of the Universe. The remaining 95% is split between dark matter (around 27%) and dark energy (around 68%). Neither dark matter nor dark energy absorbs, emits, or reflects light; neither interacts with the electromagnetic field. Both are detected solely through their gravitational effects — through how they shape the motion and form of visible objects.
It's worth pausing on that number. Not ten percent. Not fifty. Five. All of science, all of technology, the entire accumulated human toolkit of inquiry — from the microscope to the collider — works on a thin film of reality, behind which stands something we know exactly one thing about: it exists. We've given it names — "dark matter," "dark energy" — as if naming the unknown makes it known.
A name without understanding behind it remains a pointer to a blank space on our map of the world.
II. Two Mysteries, One Structure
In the history of science there are two questions joined by something deeper than difficulty. They're built the same way: we observe the consequences but have no access to the cause.
The first — dark matter. We see stars at the edges of spiral galaxies rotating faster than the mass of visible matter allows. We see gravitational lensing — the bending of light from distant galaxies under the pull of gravity — distorting images as if a mass that "isn't there" sits between source and observer. We see galactic clusters behaving as if six-sevenths of their mass is invisible. The effect is undeniable; the cause remains unknown.
Dark matter forms the gravitational scaffolding along which the entire large-scale structure of the Universe is organized — the so-called cosmic web: a gigantic network of filaments and nodes where galaxies and their clusters accumulate. Without dark matter, galaxies would not have gathered into clusters, and clusters would not have strung themselves into filaments. Dark matter plays the role of the invisible architect of the entire visible Universe.
The second question — consciousness. We observe its consequences everywhere: behavior, speech, creativity, reflection, subjective experience. But when we look for consciousness inside the brain, we find neurons, synapses, electrochemical signals — and no single place where consciousness "lives." We see correlates — neural activity accompanying conscious experience — but the cause of that experience eludes us. The neuroscientists Christof Koch and Giulio Tononi, in developing Integrated Information Theory (IIT), have essentially acknowledged: consciousness itself remains what the philosopher David Chalmers named in 1995 the hard problem — why the work of neurons is accompanied by subjective experience at all, by the feeling of "what it is like" to be, still has no explanation.
Both mysteries are built the same way: an invisible substrate governs the behavior of a visible system. In one case — the behavior of galaxies. In the other — the behavior of organisms.
Perhaps this is coincidence. But a coincidence of this magnitude deserves close attention.
III. A Pattern That Does Not Stay Silent
In 2020, the astrophysicist Franco Vazza of the University of Bologna and the neurosurgeon Alberto Feletti of the University of Verona published in Frontiers in Physics a quantitative comparison between two of the most complex known systems: the neuronal network of the human brain and the cosmic web.
The results were unexpected. If you look at how matter density is distributed in the cerebellar neuronal network at scales from 1 micrometer to 0.1 millimeter and compare it with the distribution of matter in the cosmic web at scales from 5 million to 500 million light-years, both distributions obey the same mathematical law. The scale difference between the two systems is 27 orders of magnitude (a one followed by twenty-seven zeros). And yet the pattern is one.
Vazza and Feletti also compared the network characteristics of both systems: how many connections on average run through each node, how strongly nodes tend to cluster together, whether the network develops "central hubs" that accumulate disproportionately many connections. In the authors' own words, the results showed an "unexpected level of agreement." The brain contains about 69 billion neurons; the observable Universe — about 100 billion galaxies. In the brain, neurons account for about 30% of the mass, with the rest made up of support cells (glia) and the intercellular medium. In the Universe, visible matter accounts for about 5%, with the rest made up of dark matter and dark energy. In both cases, the visible component, the smaller fraction by mass, is organized into complex filamentary structures linked by nodes.
A caveat is warranted here, one the authors themselves raise. Structural similarity between self-organizing systems at different scales is a well-known property of complex systems. River deltas, vascular networks, lightning, fungal mycelium — all form similar filamentary patterns, and none of that implies the Nile Delta is conscious. Power-law distributions and fractal structures emerge wherever certain classes of dynamical processes are at work. The similarity between the brain and the Universe might simply point to shared principles of self-organization.
Fair criticism — with a limit. Vazza and Feletti emphasize: the resemblance between the brain and the cosmic web turns out to be closer than the resemblance between either of these systems and other filamentary structures — clouds, branching networks, random fractal surfaces. Brain and Universe show a specific parameter match that goes beyond the trivial similarity between any two fractals. The question of why these two systems are so alike remains open.
IV. The Invisible Framework
To appreciate the parallel between dark matter and consciousness, one has to specify what dark matter actually does on the cosmological scale — its role is far from passive.
Dark matter functions as the scaffolding of the entire visible Universe. After the Big Bang, it was dark matter that began forming the first gravitational "wells" — regions of heightened density that pulled in ordinary matter. Along those wells, ordinary matter gradually collected into gas clouds, stars, and galaxies. Without dark matter, the gravity of visible matter alone would not have been enough to produce the complex hierarchical structure we observe. The invisible component set the shape; the visible one filled it in.
Carry that model over to the problem of consciousness, and a parallel becomes hard to miss. Consciousness, which we cannot see, measure, or localize, nonetheless determines the behavior of visible systems — organisms. Neural activity, which we can observe, serves as the analog of visible matter: real and measurable, yet perhaps not exhausting what lies behind observable behavior. Something else shapes the framework, something we cannot yet see.
A structural analogy is not yet proof. But analogies of this kind occasionally turn out to be prophetic: Maxwell noticed a similarity between electromagnetism and hydrodynamics — and wrote down the equations that described light. An analogy proves nothing by itself, but when it appears at the intersection of the two largest unknowns in science, it deserves investigation.
V. What If They Are the Same Thing?
Assume for a moment that the analogy points to something deeper. What if dark matter and consciousness are two manifestations of the same unknown?
The idea looks audacious but rests on several independent lines of thought.
The first — panpsychism in its modern, far-from-mystical form. The philosophers Galen Strawson and Philip Goff, together with the neuroscientist Christof Koch, propose that the capacity for experience (sometimes called proto-consciousness) may be a fundamental property of matter — as basic as mass or electric charge. The electron, in this view, does not "think." Rather, some "inner aspect" — a minimal form of what we experience at a higher level as consciousness — is present everywhere, and our conscious experience represents its complex, highly integrated form.
The second — the aforementioned Integrated Information Theory (IIT) of Tononi. It holds that consciousness is a property of systems with a high degree of integrated information, measured by the number Φ (phi): the more interconnected and mutually dependent a system's parts are, the higher Φ, and the more "conscious" the system. Apply that logic to the cosmic web — and the Vazza-Feletti study shows its network parameters are comparable to those of a neural network — and an uncomfortable question arises: does the Universe as a whole possess a non-zero Φ? IIT formally permits the possibility, though computing Φ for a system of cosmological scale is currently beyond us.
The third — neutral monism, the philosophical position developed by Bertrand Russell and the astrophysicist Arthur Eddington. The core claim: physics describes only the structural properties of matter — how things relate to each other, how they interact, what laws they obey. But what things are in themselves — their "intrinsic nature" — physics does not describe. Russell suggested that this intrinsic nature might be something like experience. On that view, dark matter becomes matter whose intrinsic nature is as inaccessible to us as the intrinsic nature of consciousness.
VI. The Framework and the Agents
In the essay "Consciousness as a Network," a metaphor was proposed: humans are agents of a single consciousness, much as AI agents are individual activations of a single language model. If dark matter and consciousness are indeed connected, the metaphor gains an additional layer.
Dark matter forms the cosmic framework — the invisible net along which the visible Universe is organized. Grant the framework an inner aspect, proto-consciousness, and it performs the same function that the base model performs in the AI metaphor: a single substrate from which individual agents are activated.
In this picture, the brain stands as a node where the invisible substrate reaches an especially high degree of integration. Just as dark-matter gravitational wells collect ordinary matter into galaxies, the neural network of the brain "collects" diffuse proto-consciousness and focuses it into individual subjective experience. Neurons, in such a model, serve as focal points for a diffuse substrate that already exists.
In cosmology, regions where dark matter is especially dense have a specific name — dark matter halo. Every galaxy is surrounded by such a halo — an invisible sphere whose mass far exceeds that of the visible galaxy and which determines the galaxy's rotation, form, and evolution.
What if the brain is a kind of "consciousness halo"? A region where the invisible substrate thickens to the point that subjective experience emerges — one of the densest points in the Universe, but far from the only one.
VII. What We Don't Know (and Why It Matters)
Honesty about the limits of what's been said is essential.
We don't know what dark matter is. The ΛCDM model describes its gravitational effects successfully, but the nature of the particles (if particles are what we're dealing with) remains unknown. The main candidates — WIMPs (weakly interacting massive particles), axions, sterile neutrinos, and primordial black holes — none have been directly detected in any experiment. Alternative approaches exist, such as MOND (Modified Newtonian Dynamics), which explains some observations without dark matter but runs into serious difficulties at cosmological scales. In 2024, Professor Rajendra Gupta of the University of Ottawa published work proposing a model of the Universe with no dark matter at all, though the work remains marginal.
We don't know what consciousness is. There is no consensus theory. IIT, Global Workspace Theory, higher-order theories, predictive coding — competing hypotheses, none confirmed by a decisive experiment.
We know even less whether dark matter and consciousness are connected. A structural analogy between two phenomena is not yet a causal link. The hypothesis that dark matter may possess an inner aspect — proto-consciousness — remains a speculation that currently cannot be tested experimentally.
Here's what we do know: both mysteries concern the invisible governing the visible. Both steadfastly resist reduction to known physical mechanisms.
And both point to the same blank spot in our picture of reality.
VIII. Naming the Unknown
There's an ironic symmetry in how we treat what we don't understand. We call invisible mass "dark matter" — as if the adjective "dark" explained anything. We call the source of subjective experience "consciousness" — as if the noun replaced understanding. Both terms perform the same function: they mark the boundary of knowledge, creating the illusion that to name is to understand.
The fact that we do not see 95% of the Universe — a reminder of the radical limits on our access to reality. We are agents with a narrow context window, trying to describe a system ninety-five percent of which lies beyond our perception. And the only thing available to us from those invisible ninety-five percent — effects: gravitational and subjective.
Perhaps one day physics and the science of consciousness will converge at a single point and discover they were studying the same mystery from different sides all along. Perhaps they will remain parallel unknowns. But either way, the simple fact that 95% of reality is invisible, and the one thing we know for certain is that we are conscious, does not permit dismissing the possibility of a connection between the two mysteries.
We stand on five percent and look into the abyss. The abyss, perhaps, looks back.
Bibliography
- Chalmers, D.J. (1995). Facing Up to the Problem of Consciousness. Journal of Consciousness Studies, 2(3), 200–219.
- Goff, P. (2019). Galileo's Error: Foundations for a New Science of Consciousness. Pantheon Books.
- Gupta, R.P. (2024). Testing CCC+TL Cosmology with Observed Baryon Acoustic Oscillation Features. The Astrophysical Journal, 964(1), 55.
- Koch, C. (2012). Consciousness: Confessions of a Romantic Reductionist. MIT Press.
- Planck Collaboration (2018). Planck 2018 Results. VI. Cosmological Parameters. Astronomy & Astrophysics, 641, A6.
- Russell, B. (1927). The Analysis of Matter. Kegan Paul.
- Strawson, G. (2006). Realistic Monism: Why Physicalism Entails Panpsychism. Journal of Consciousness Studies, 13(10–11), 3–31.
- Tononi, G. (2004). An Information Integration Theory of Consciousness. BMC Neuroscience, 5, 42.
- Vazza, F. & Feletti, A. (2020). The Quantitative Comparison Between the Neuronal Network and the Cosmic Web. Frontiers in Physics, 8, 525731.