In the late 1940s, a young physicist named David Bohm sat at the Lawrence Radiation Laboratory in Berkeley watching electrons move through a plasma, and what he saw unsettled him for the rest of his life. In the ionized gas, the individual electrons did not behave as isolated particles bouncing at random. They moved collectively, organizing themselves, screening out disturbances, behaving — as Bohm later put it — "as if they were alive." The sea of electrons acted like a single coordinated organism whose parts seemed to know what the whole was doing. Bohm could not shake the impression that he had glimpsed something the standard picture of physics, with its discrete particles and their local collisions, was structurally unable to express: an undivided wholeness, prior to the parts, of which the parts were only abstractions. From that perception grew one of the strangest and most influential ideas of the twentieth century — and, eventually, one of the most thoroughly misunderstood.
The misunderstanding has a precise shape. Two completely different ideas now travel under the single banner of "the holographic universe," and the public conversation has welded them into one. The first is a philosophy of mind and cosmos — Bohm's implicate order, fused with the brain research of Karl Pribram and popularized by the journalist Michael Talbot — which holds that the whole is enfolded into every part, the way a hologram stores the entire image in each fragment of the plate. The second is a precise and quantitatively tested result in theoretical physics — the holographic principle of Gerard 't Hooft, Leonard Susskind, and Juan Maldacena — which holds that the information content of a volume of space is bounded by, and can be encoded on, its surrounding surface. The two share a word and a metaphor and almost nothing else. They were proposed by different people, in different decades, to answer different questions, using different methods. Keeping them apart is not pedantry. It is the whole task, because the value and the confusion both live exactly at the seam where they are conflated.
The optical hologram, invented by the Hungarian-British engineer Dennis Gabor in 1948 — work that earned him the 1971 Nobel Prize in Physics once the laser made it practical — has one property that captivates everyone who learns it. An ordinary photograph records light intensity point by point; cut it in half and you lose half the picture. A hologram instead records the interference pattern produced when light scattered off an object meets a coherent reference beam, and that pattern is smeared across the entire plate. Illuminate the developed plate with the reference beam again and the original three-dimensional scene reappears, floating, viewable from different angles.
The astonishing part comes next. Cut a hologram into pieces and each piece still reconstructs the whole scene, only at lower resolution and from a narrower window. The information about every part of the image is distributed across every part of the plate. The whole is in each fragment. This single fact is the seed of everything on the mystical side of the story, and it is the image David Bohm reached for when he tried to name what he had seen in the plasma.
Bohm had earned the right to distrust the standard picture the hard way. A protégé of Robert Oppenheimer, he wrote a textbook on quantum theory in 1951 so lucid that Einstein told him it was the clearest account he had read — and then, in person, persuaded Bohm that the orthodox Copenhagen interpretation could not be the final word. That same year Bohm was subpoenaed by the House Un-American Activities Committee, refused to inform on colleagues, was indicted, acquitted, and effectively exiled from American physics; he spent the rest of his career in Brazil, Israel, and Britain. The isolation gave him room to pursue the heresy he had been nursing. In 1952 he published his "hidden variables" or pilot-wave interpretation, reviving an idea of Louis de Broglie's and proving — against the prevailing dogma that von Neumann had supposedly ruled it out — that quantum mechanics could be given a deterministic, realist account in which particles always have definite positions, guided by what he called a "quantum potential." That potential was nonlocal: it linked distant particles instantaneously, knitting the universe into a single connected system. Wholeness, for Bohm, was not a mood. It fell out of his equations.
The nonlocality was not a quirk of Bohm's particular interpretation, either. In 1964 the physicist John Bell, explicitly inspired by Bohm's hidden-variable model, proved a theorem showing that no theory built on local, separable parts could reproduce all the predictions of quantum mechanics — that any theory matching the experiments must contain instantaneous correlations between distant events. When Alain Aspect's experiments in the early 1980s, and a wave of ever-tighter "loophole-free" tests culminating in the work that won the 2022 Nobel Prize, confirmed those correlations, they confirmed that the world really is nonlocally connected in just the way Bohm's wholeness required. This is the legitimate scientific kernel of the implicate order: entanglement is real, the universe does not decompose cleanly into independent pieces, and the intuition Bohm took from the plasma has empirical teeth. Everything Talbot later built on top of it is a separate question.
In Wholeness and the Implicate Order (1980), Bohm generalized that insight into a cosmology. The universe we perceive — the explicate order of separate objects laid out side by side in space and time — is, he argued, the unfolding of a deeper implicate order in which everything is enfolded into everything else. His favorite demonstration was a glycerine apparatus: a drop of ink stirred into highly viscous fluid by a slowly rotating cylinder disperses until it vanishes from sight, then reassembles into a droplet when the rotation is reversed. The ink was never gone. It was enfolded, distributed through the medium, its order hidden rather than destroyed, and the visible droplet was a momentary explication of it. Reality, Bohm proposed, is a holomovement — an unbroken flowing whole continuously enfolding and unfolding, of which particles, fields, and even spacetime itself are relatively stable surface features, like recurrent eddies in a river that has no separate parts.
The holographic image was, for Bohm, more than an analogy. A photograph maps each point of an object to a corresponding point on the film — a one-to-one, explicate correspondence. A hologram does the opposite: each region of the object affects the entire plate, and each region of the plate carries the whole object, an enfolded, implicate correspondence. He took this as a hint about the deep structure of matter, and his later collaborator Basil Hiley worked to give it mathematical body in The Undivided Universe (1993). Bohm extended the enfolding to time as well, which makes him a natural correspondent of the question of The Nature of Time: in the implicate order, past and future are not laid out along a line but enfolded together in a timeless ground, and the river of moments we experience is only the order in which the whole reads itself out. In his last work he pushed even further, toward "soma-significance" and the suggestion that meaning, mind, and matter are aspects of one undivided process — an idea he developed across decades of recorded dialogue with the Indian teacher Jiddu Krishnamurti, who convinced him that thought itself fragments a reality that is not actually divided.
Karl Pribram supplied the second pillar, and he supplied it from neuroscience rather than physics. A distinguished Stanford neurosurgeon and neuroscientist, Pribram had spent decades on the problem of memory — specifically Karl Lashley's stubborn finding, accumulated across thirty years of lesion experiments, that a memory is not stored in any single location and survives the removal of large and arbitrary portions of cortex. Where, then, does the memory live? In the 1960s Pribram, struck by Bohm's work and by the mathematics of holography, proposed that the brain stores information the way a hologram does: not in discrete cells but in distributed interference patterns spread across populations of neurons, so that any sufficient fragment of the tissue can still reconstruct the whole. Perception, in his holonomic brain theory, is a kind of Fourier transform — the brain decomposing sensory input into a frequency domain and reconstructing the experienced world from it. The proposal drew real empirical support: the receptive fields of neurons in the visual cortex are well described by "Gabor functions," the very wavelets Gabor had used for holography, and the brain's resilience to localized damage is genuine. Bohm had given the cosmos a holographic structure; Pribram gave the mind one.
Michael Talbot fused the two pillars into a single sweeping edifice. A journalist and author with a long-standing interest in the paranormal, Talbot published The Holographic Universe in 1991 — the book that fixed the phrase in popular imagination. His thesis was elegant and total: a holographic brain reading a holographic universe, mind and matter alike enfoldings of one undivided order, separateness an illusion of the explicate surface. From this scaffold he hung an enormous range of claims — telepathy and clairvoyance, near-death and out-of-body experiences, lucid dreaming, synchronicity, psychokinesis, even miraculous healing and stigmata — arguing that all become intelligible once you accept that each part of reality contains the whole and that Consciousness participates directly in the enfolded order. Talbot died of leukemia the next year, at thirty-eight, and never wrote the sequel he had planned. The book, however, sold steadily for decades and became the canonical statement of the "holographic paradigm," a phrase that had been circulating among consciousness researchers since the 1970s and that now signaled, for a wide audience, that science had discovered the mystics were right.
The other holographic universe begins not with wholeness but with a paradox about black holes, and it has nothing to do with mysticism. In 1972, a graduate student named Jacob Bekenstein, working under John Wheeler at Princeton, worried over what happens to entropy — the thermodynamic measure of disorder, and equivalently of hidden information — when you drop a hot object into a black hole. If the object simply vanishes behind the event horizon, the entropy of the outside universe decreases, which would violate the second law of thermodynamics, the most secure law in physics. Wheeler put the problem to Bekenstein as a provocation: a cup of hot tea poured into a black hole seems to erase its disorder from the books. Bekenstein's radical answer, published in 1973, was that the black hole itself must carry entropy, and that this entropy is proportional not to the black hole's volume but to the area of its event horizon — so that anything falling in increases the horizon's area, and the second law is saved in a generalized form.
Stephen Hawking initially objected. Entropy implies temperature, temperature implies radiation, and a black hole was by definition supposed to be perfectly black, emitting nothing. Then in 1974, applying quantum field theory to the curved spacetime just outside the horizon, Hawking found to his own surprise that black holes do radiate — that pairs of virtual particles near the horizon can be split, one falling in and one escaping, so that the hole glows with a faint thermal spectrum and very slowly evaporates. The calculation converted Bekenstein's bookkeeping trick into hard physics and fixed the constant exactly: a black hole's entropy is one quarter of its horizon area, measured in Planck units, with each unit of area roughly the size of a Planck length squared. The Bekenstein-Hawking entropy is one of the few results in physics that joins gravity, quantum mechanics, and thermodynamics in a single formula, and it has survived every theoretical test for half a century.
The crack through which the holographic principle came is the word area. Entropy counts the number of distinguishable quantum states — the bits of information — needed to fully specify a system. For ordinary objects that count scales with volume: double the box, double the storage. But Bekenstein's result implies that the maximum information that can be packed into any region of space, before it collapses under its own weight into a black hole, scales not with the region's volume but with the area of its boundary. This is the Bekenstein bound, and its implication is vertiginous: a sphere of space can hold no more information than can be written on its surface, at the absurd density of roughly one bit per four Planck areas — about 10^69 bits per square meter. Everything that can possibly be happening inside this room is captured, without loss, by a description living on the room's walls. The interior is, informationally, redundant.
Gerard 't Hooft, the Dutch Nobel laureate, drew the audacious general conclusion in a 1993 paper, "Dimensional Reduction in Quantum Gravity": the complete physics of any volume can be encoded on its lower-dimensional boundary. Leonard Susskind sharpened it and gave it its name in his 1995 paper "The World as a Hologram," casting it in the language of string theory. The three-dimensional world might be a kind of hologram, its full content written on a two-dimensional surface, not as a poetic flourish but as a literal count of degrees of freedom.
For four years this was a beautiful conjecture without a concrete model — a principle in search of a worked example. Then in 1997, Juan Maldacena, then at Harvard, produced what became the most cited paper in the history of theoretical physics. His AdS/CFT correspondence exhibited an exact mathematical equivalence — a duality — between a theory of gravity living in a five-dimensional "anti-de Sitter" spacetime and an ordinary quantum field theory, with no gravity at all, living on that spacetime's four-dimensional boundary. Every physical question in the gravitational "bulk" has a precise translation into a question in the boundary theory, and vice versa; the two descriptions are not approximations of each other but the very same physics written in two languages. A black hole forming and evaporating in the bulk corresponds to a hot plasma thermalizing and cooling on the boundary. The principle had become a calculational instrument.
The instrument works. Physicists now routinely attack problems they cannot solve directly in a strongly interacting quantum system by translating them, through the dictionary, into tractable problems about curved spacetime and black holes one dimension up — and back again. The technique has been applied to the quark-gluon plasma produced in heavy-ion colliders, to exotic states in condensed-matter physics, and to the deep structure of quantum entanglement. AdS/CFT is the reason the holographic principle is taken seriously rather than treated as numerology: it is the one place where "the bulk is encoded on the boundary" stops being a slogan and becomes a theorem with a dictionary attached. And it is precisely this result — depth and gravity reconstructed from information on a surface — that makes the holographic universe the strongest physics-adjacent foothold for the The Simulation Hypothesis. If the apparent three-dimensional world is genuinely reconstructed from data living on a boundary, then reality is, in a literal and quantitative sense, encoded and unpacked, the way a rendered scene is unpacked from the numbers in a memory buffer.
The holographic principle was not discovered in calm. It was forged in a thirty-year argument over what happens to information that falls into a black hole — a fight Susskind later recounted, with relish, in The Black Hole War (2008). Hawking's own 1974 calculation implied that an evaporating black hole turns into featureless thermal radiation and then disappears, carrying away every distinction between the things that fell in. A library and a bomb of the same mass would leave identical ash. In 1981 Hawking declared, on exactly this basis, that black holes destroy information outright. To most physicists this was intolerable, because the destruction of information violates the bedrock rule of quantum mechanics — unitarity — that the present state of any system always determines, and is determined by, its past, with nothing ever truly lost. If black holes broke that rule, the consistency of physics itself was at stake.
Susskind and 't Hooft refused to accept the loss. The holographic principle was, in significant part, their weapon. If everything that falls into a black hole is also recorded on its horizon — on the two-dimensional surface — then the information is never destroyed; it is encoded on the boundary and gradually leaks back out in the subtle quantum correlations of the escaping Hawking radiation. To reconcile this with the experience of someone falling in, who notices nothing special at the horizon, Susskind proposed black hole complementarity: an infalling observer sees herself cross the horizon intact, while a distant observer sees her information thermalized and spread across the surface, and — because no single observer can ever stand in both frames to compare notes — there is no contradiction, only two complementary descriptions of one reality. The idea was elegant, disturbing, and nearly broken again in 2012, when Joseph Polchinski and three colleagues argued that full consistency might demand a "firewall" of lethal high-energy radiation at the horizon, contradicting Einstein's principle that crossing a horizon should be uneventful. The firewall paradox reopened the war in a new key and remains only partly resolved.
What ultimately turned the field was the marriage of holography to entanglement. In 2006 Shinsei Ryu and Tadashi Takayanagi proved, within AdS/CFT, that the entanglement entropy of a region of the boundary theory is measured by the area of a minimal surface reaching into the bulk — meaning that the geometry of space in the interior is, somehow, constructed out of the pattern of quantum entanglement among the bits on the edge. Cut the entanglement and the spacetime falls apart; weave it and the smooth depth and curvature appear. This is the "it from qubit" program, and its boldest slogan, due to Maldacena and Susskind, is ER = EPR: that the wormholes of general relativity and the entangled pairs of quantum mechanics are the same phenomenon seen two ways. Hawking, who had bet a baseball encyclopedia against information loss and held the losing side for decades, conceded publicly in 2004.
The program has since reached far enough to leave the chalkboard. In 2010 Erik Verlinde proposed that gravity itself is not a fundamental force at all but an entropic one — a statistical tendency that emerges from changes in the information stored on holographic screens, in the same way that the elasticity of a stretched polymer emerges from the statistics of its tangled molecules rather than from any fundamental restoring force. The idea is contested, but it is a direct child of the holographic principle, and it reframes Newton's law of gravity as a consequence of information on surfaces. In 2019 the first image of a black hole's shadow, from the Event Horizon Telescope, gave the horizons that anchor the whole story a literal photograph. And in 2022 a team using Google's Sycamore quantum processor simulated the dynamics of a "traversable wormhole" — not an actual hole in spacetime but the boundary-theory description that, through the holographic dictionary, corresponds to one — a vivid demonstration that the bulk-boundary correspondence is concrete enough to run, in miniature, on a real machine. The holographic universe of the physicists is, at bottom, the claim that spacetime geometry is the readout of entangled quantum information — a claim won in hard argument, written in equations, tested in dualities, and entirely, conspicuously silent about anything mystical.
Now place the two universes side by side and the trouble becomes unmissable. Talbot's The Holographic Universe appeared in 1991 — four years before Susskind named the holographic principle and six before Maldacena wrote down the correspondence. Talbot was writing about Bohm and Pribram, about enfolded wholeness and holographic memory, reaching toward psi, mystical unity, and the participation of mind in reality. He was not writing about black-hole entropy, which physicists were still arguing over, and he could not have cited AdS/CFT, which did not yet exist. The two ideas were never in contact at their origin. Yet because both can be glossed in the same six words — "the universe is a hologram" — the popular mind folds them seamlessly into one. A viewer encounters Susskind on a documentary saying the world may be a hologram, half-remembers Talbot's claim that every part contains the whole, recalls something vague about observation creating reality, and assembles a single doctrine: physics has now proven that the universe is an illusion generated by consciousness, and that all things are one.
The channel for this fusion was already worn smooth. Fritjof Capra's The Tao of Physics (1975) and Gary Zukav's The Dancing Wu Li Masters (1979) had trained a generation to read quantum formalism as scientific confirmation of Eastern mysticism, and the holographic metaphor slotted neatly into that established groove. Bohm's own late dialogues with Krishnamurti, his sympathy for the perennial philosophy, and Pribram's open willingness to discuss the paranormal lent the synthesis a patina of insider authority — these were, after all, a serious quantum theorist and a distinguished neuroscientist, not cranks. By the 2000s the fused doctrine had its own media ecosystem: the film What the Bleep Do We Know!? (2004), the wellness empire of Deepak Chopra, a steady stream of documentaries intoning that "scientists now believe the universe is a hologram," and an endless supply of online explainers that quote Susskind in one sentence and Talbot in the next. "Holographic universe" had become a brand, detached from either body of work that produced it, carrying a single uplifting message: matter is not solid, separation is illusion, mind is fundamental, and physics agrees.
The fusion is seductive because each side supplies precisely what the other lacks. Bohm and Talbot offer meaning, wholeness, and a central role for mind — but no equations, no predictions, and no testable consequences. 't Hooft, Susskind, and Maldacena offer rigor, mathematics, dualities, and Nobel-grade credibility — but say nothing whatever about consciousness, mysticism, or cosmic oneness. Splice the two and you obtain a doctrine that feels at once spiritually profound and scientifically certified, which is exactly why it spreads so freely. The deepest irony is biographical. Bohm, whose realist pilot-wave interpretation was for decades dismissed and marginalized by the same mainstream that built the holographic principle, has been retroactively annexed to a result that has nothing to do with his hidden variables and that his exilers' successors authored — while those physicists, for their part, would not recognize the implicate order, soma-significance, or holonomic memory as any part of the structure they discovered.
So the strongest counter is not that either idea is false. It is that they are different claims, established by different means, and they must be judged separately rather than allowed to borrow each other's authority. Take the physics first, on its own terms. The holographic principle is a precise statement about the information capacity of regions of space, together with a conjectured-then-demonstrated duality between gravitational and non-gravitational descriptions of the same system. It says that the number of degrees of freedom available in any volume is bounded by the area of its boundary, and that certain gravitational theories have exact boundary duals. That is an extraordinary claim about information and gravity. It is not a claim about illusion or about mind.
What the holographic principle does not say is the whole content of the clarification. It does not say the universe is an illusion: in AdS/CFT both descriptions, bulk and boundary, are equally real and equally physical, two faithful accounts of one system rather than a real thing and its fake shadow. It does not say that observation or consciousness creates reality: the boundary theory evolves under its own dynamics whether or not any observer exists, and there is no term anywhere in the formalism for a mind, an intention, or an act of awareness. It does not say "we are all one" in any sense a mystic would recognize; the "oneness" of holography is the technical statement that bulk and boundary carry the same information, not a dissolution of persons into cosmic unity. And the "2D surface" is not a projection screen and the "hologram" is not a deception — nothing is being fooled and no one is being shown a false world.
The encoding is a structural fact about how information and gravity relate, derived from black-hole thermodynamics and string theory, with no observer and no illusion anywhere in the derivation. The word "hologram" was borrowed for the technical sense in which one piece of a region's description suffices to reconstruct more than you would expect — not for any of the connotations of unreality the popular phrase has since acquired.
The physics also carries an honest limitation that the popular version omits. The only spacetime in which the holographic correspondence has been exactly established is anti-de Sitter space, which is negatively curved and has a boundary at infinity, like the inside of a saddle that wraps around on itself. Our actual universe is, as far as we can measure, expanding and slightly positively curved — a de Sitter-like space with no such convenient boundary — and constructing a fully worked holographic description of a universe like ours remains an unsolved and actively contested problem. So even the strong claim "reality is holographic" is, at the frontier, a hope guided by a theorem proven in a different geometry, not a settled fact about the world we inhabit. The principle is profound and may well generalize; it has not yet been shown to.
It is worth noting that, unlike the mystical paradigm, the physics version has at least been put to an experimental test — and the test is instructive precisely because of what it did and did not target. The physicist Craig Hogan reasoned that if space is fundamentally made of a finite number of holographic bits, there should be a residual jitter — "holographic noise" — in the position of objects at the smallest scales, a faint blurring inherited from the limited information available to specify where anything is. Beginning around 2014, Fermilab built the Holometer, a pair of forty-meter laser interferometers, expressly to look for that noise. It found none at the predicted level, ruling out Hogan's specific model. The result is often misreported as having "tested whether the universe is a hologram"; it did no such thing. It tested one narrow, concrete proposal about how holographic granularity might manifest. The broader holographic principle survives untouched, because it never predicted Hogan's noise in the first place — a useful reminder of how much careful work separates a falsifiable physical hypothesis from the unfalsifiable slogan it is mistaken for.
Now the paradigm, also at full strength. Bohm's implicate order is serious philosophy of physics, motivated by real and unresolved puzzles — quantum nonlocality, the measurement problem, the manifest wholeness revealed by entanglement — and Bohm was a first-rate physicist whose pilot-wave theory remains a live, empirically equivalent interpretation of quantum mechanics that working physicists still develop. The implicate order is a defensible and in some ways beautiful picture of reality as a single undivided process. But it is interpretive metaphysics, not a derived consequence of any experiment, and it issues no distinct prediction that could distinguish it from rival pictures. Pribram's holonomic theory is a genuine model in cognitive neuroscience, partly vindicated — the brain really does use distributed, frequency-domain-like coding — and partly superseded by later work. Talbot's leap from these foundations to telepathy, miraculous healing, and a consciousness-generated cosmos is extrapolation that neither Bohm's physics nor Pribram's neuroscience licenses, however eloquently it is made.
Held side by side, then, the two holographic universes ask to be respected for what each actually is. The implicate-order vision is philosophy reaching toward physics — and it may even rhyme with where entanglement-based gravity is heading, which is part of why it refuses to die. The holographic principle is hard physics reaching toward a new picture of spacetime — and it is silent on mind, illusion, and oneness by construction, not by oversight. This is the same boundary that runs through every "quantum" appropriation of the deep sciences, and the temptation to read Idealism straight off the equations is strongest exactly where the equations are least understood by the reader. The honest position keeps both universes in view at once and refuses to let the single word they happen to share do the arguing for either.
What survives the separation turns out to be more interesting than the conflation it replaces. Two entirely independent intellectual traditions, starting from incompatible places — one from electrons that moved as if alive, the other from the entropy of black holes — arrived, by routes that never crossed, at the same arresting suspicion: that the solid three-dimensional world of separate things may be the surface readout of a deeper order in which information, not matter, is fundamental, and in which the whole is in some manner present in every part. That convergence might be pure coincidence, two metaphors colliding by accident of vocabulary. Or it might be a genuine clue about the architecture of reality, glimpsed twice from opposite directions. Either way it is worth far more held distinct — physics as physics, philosophy as philosophy — than melted into a single slogan that neither the mystics who inspired one half nor the physicists who proved the other would ever agree to sign.