Is reality fundamentally made of information?
April 2, 2026
We have always taken for granted that information flows out from reality, without ever questioning this axiom. But in recent decades, our discoveries of the world has pushed us to question the truthfulness of this heiarchy. What if reality is fundamentally made of information ?
In our everyday life, we assume reality is made of “stuff”. Things that we can interact with. But what if reality is not made of “stuff” at all, but rather of information?
Information, as first glance seems secondary: a book contains information, but the book is paper and ink. But what if that hierarchy is backward ? what if information is the primary substance, and what we call “matter” is just a particular pattern of information ?
But let slow down a second. Before going any further, we need to know and define what we are even talking about. Three words demand clarity: reality, fundamentally, and information.
What do we mean by “reality” ?
In everyday language, reality refers to the sum of all things that exist independently of our perception or thoughts. It is the world as it is, regardless of how we interpret it.
That is a good definition, yet we need to be more precise.
A useful distinction comes form ontology (the study of being and existence):
- Everyday Reality : tables, tree, the support that you are reading the blog on. This is the world of middle-sized objects. Things that you can see, hear and interact with in a familiar way.
- Scientific Reality : Here we are talking atomes, electrons, space-time curvature …
- Fundamental Reality : This is the deepest level of reality, where the basic building blocks of existence are found. It is the level at which the laws of physics operate, and where information might be considered the most fundamental aspect of reality.
When we ask Is reality fundamentally made of information ? we are asking about that third level. Not whether my phone is information (it’s clear that it’s not only information, it has also mass, heat charge …), but whether, at the bedrock level, before anything else emerges, the stuff of reality is informational in nature.
What do we mean by “Fundamentally” ?
This is the trickiest part. Something is fundamental if it doest NOT depend on anything else for its existence. It is the ground floor of reality.
For example, one can say that atomes are the fundamental building blocks of everyday reality. However, atomes are made of protons neutrons and electrons, which are in turn made of quarks. So the question arises: what is the most fundamental level of reality? are quarks fundamental ?
Fundamentally also implies primacy in explanation. If you could explain everything else in terms of X, but you cannot explain X in terms of anything else, then X is fundamental. So the question becomes: can we explain matter, energy, space, and time in terms of information? And if we try to explain information in terms of matter, does that fail?
What do we mean by “information” ?
For Claude Shannon, he defined information as redcution of uncertainty. More precisely: The information content of a message is measured by how suprising it is. A coin flip that comes up heads gives you 1 bit of information because it could have gone either way. The sun rising tomorrow gives you almost 0 bits because you already knew it would happen.
This is what we call statistical information. In the other hand, there is also semantic information. The sentence “Brian is in the kitchen” contains information about the world. This is closer to what we mean in daily life. But it’s harder to formalize. Kitchen contains no semantic information on its own. Only when a mind interprets it, it start to “exist”.
Then for our third layer, there is physical information : Laundauer’s principle shows that information has physical reality. Erasing a bit generates heat. (see in the appendix for more details). Thus information is not just abstract; it’s deeply tied to entropy.
Finally, the last but not the least : Qauntum information: A qubit can be in a superposition of 0 and 1. It contains more possibilities than a classical bit. The quantum state of a particle is, arguably, a form of information about measurement outcomes.
To summarize. When we ask if reality is fundamentally made of information. We usually mean Shannon information or Quantum information (The mathematical, measurable physical kind). Not the meaning in a human brain. A single electron doesn’t know any “facts.” But its state can be described by a handful of bits.
Now we went from : Is reality fundamentally made of information ? to :
Are the ultimate, irreducible constituents of physical reality, the things that do not depend on any other things, constituted solely by discrete, quantifiable units of (perhaps quantum) information, such that what we call matter, energy, space, and time are emergent patterns of that information?
That’s a mouthful. But now that the question is sharp, we can stop philosophizing and ask the only question a physicist really cares about: does nature actually behave as if this were true? Let’s follow the clues.
From philosophy to physics
Here is the thing. Physicists don’t get to decide what reality is made of by arguing about definitions. We look at how the world behaves, and we let the equations tell us what matters. And over the last century, something strange happened: every time we pushed physics to its limits, information kept showing up where we least expected it, not as a metaphor, but sitting right there inside the equations.
Let me walk you through four clues. None of them is a proof. Together, they are hard to ignore.
Clue 1 — Wheeler’s wager: “It from Bit”
The physicist John Archibald Wheeler, the same man who coined the term “black hole”, spent the last part of his career on a slogan: “It from Bit.”
His claim, in his own words, was that every particle, every field of force, even spacetime itself, derives its existence from answers to yes-or-no questions, binary choices, bits. The “it”, the physical thing, comes from the “bit”, the information.
Why would a serious physicist believe something so radical? Because of quantum mechanics. In the quantum world, a particle does not have a definite position or spin until you ask, until you measure. Before the measurement, all you have is a set of probabilities: a description of what answers you might get. Reality, at that level, looks less like a collection of tiny billiard balls and more like a collection of potential answers to questions. Wheeler took that seriously and asked: what if the questions and answers are the whole story?
It was a wager, not a theorem. But it reframed the game.
Clue 2 — The thermodynamic clue: erasing a bit costs heat
Here is where information stops being an abstraction and starts having a temperature.
In 1961, Rolf Landauer proved something remarkable: erasing one bit of information has an unavoidable physical cost. To wipe a single bit, you must dump at least k T ln 2 of energy into the environment as heat, where T is the temperature and k is Boltzmann’s constant (more on this in the appendix).
Read that again. A logical operation, deleting information, forces a physical consequence, waste heat. Information is not floating in some abstract realm separate from physics. It is welded to thermodynamics, to entropy, to energy. In 2012 this was measured directly in the lab. It is real.
This is the first crack in the old hierarchy. We used to say: matter is primary, information is just something we write about matter. But if rearranging information necessarily heats up the universe, then information is not a passive description sitting on top of reality. It is participating in the physics.
Clue 3 — Black holes and the surface that shouldn’t be there
Now the strangest clue of all.
Ask a physicist: how much information can you cram into a region of space, say a sphere the size of a basketball? Naively, you’d think the answer scales with the volume, more room inside, more stuff you can fit. That’s the common-sense answer.
It’s wrong.
When you study black holes, the objects with the most extreme gravity in the universe, you find that the maximum information a region can hold scales with its surface area, not its volume. This is the Bekenstein–Hawking result: a black hole’s entropy, which is a measure of the hidden information swallowed inside it, is proportional to the area of its horizon, counted in tiny squares each about one Planck length on a side.
Think about how bizarre that is. Everything that ever fell into the black hole, all its matter, all its history, has its information budget set by the area of the boundary, as if the inside were just a projection of the surface.
Clue 4 — The holographic principle: reality as a projection
Clue 3 led Gerard ‘t Hooft and Leonard Susskind to a stunning conjecture: the holographic principle. If the information content of any region is fixed by its boundary area, then perhaps a three-dimensional chunk of reality can be fully encoded on its two-dimensional surface, the way a flat hologram stores a 3D image.
Taken seriously, this suggests the volume, the “inside”, the space we think we live in, might be derived information, reconstructed from data living on a lower-dimensional boundary. Space itself would not be fundamental. It would be a readout.
This is no longer just philosophy. In string theory there is a concrete, mathematically precise example (called the AdS/CFT correspondence) where a universe with gravity is exactly equivalent to a quantum system without gravity living on its boundary. Two descriptions, same physics. And the dictionary that translates between them is written in the language of quantum information and entanglement.
The quantum turn: from “It from Bit” to “It from Qubit”
Wheeler said bit. But we now suspect he was one letter short.
A classical bit is a definite 0 or 1. A qubit, the quantum version, can be a blend of both at once, and, crucially, qubits can be entangled: two of them can share a joint state so tightly correlated that neither has a state of its own. This is a genuinely new kind of information with no classical analogue.
And here is the punchline of modern research. When physicists ask how spacetime might emerge from information, the glue keeping it together seems to be entanglement. Work by Mark Van Raamsdonk and others suggests that if you take two regions of space and remove the entanglement between their underlying quantum bits, the geometry connecting them literally comes apart, the spacetime pulls into two disconnected pieces. Space is stitched together out of quantum correlations.
So the modern slogan is no longer “It from Bit” but “It from Qubit.” The suspicion is that spacetime and gravity are not fundamental furniture of the universe, but emergent patterns woven from a more basic fabric of entangled quantum information. That is exactly the refined question we asked, showing up as a research program.
But wait: information about what?
Now, if I only told you the clues above, I’d be a bad guide. Because there is a serious objection, and honest physics means facing it.
The objection is deceptively simple: information is always information about something. A bit tells you the answer to a question, but a question presupposes a thing you’re asking about. Shannon’s information measures the reduction of uncertainty, but uncertainty about what? If reality is nothing but information, the critics ask, then it’s information about information about information… all the way down, with nothing underneath to anchor it. A description of a description, with no thing being described.
This is the strongest arrow in the skeptic’s quiver, and it’s a good one. Some philosophers call the “it from bit” picture a category mistake: confusing our best description of reality (which is of course made of information, because all descriptions are) with reality itself.
There are two honest responses:
- The deflationary reply: maybe the objection is right, and information is just an extraordinarily powerful language for physics, not its substance. That it keeps showing up would then say more about how we do science than about what the world is made of.
- The structural reply (relational information): maybe the objection dissolves once you drop the assumption that there must be “stuff underneath”. Perhaps reality is pure relations, correlations between measurement outcomes, with no independent objects standing at the ends of those relations. In this view the electron isn’t a thing that has information; the electron is a bundle of relational information, and asking “information about what?” is like asking what the number 7 is made of. This is close to the spirit of Carlo Rovelli’s relational quantum mechanics and to structural realism in philosophy of physics.
I won’t pretend to settle this for you. Nobody has.
So, is reality fundamentally made of information?
Here is my honest verdict as of today.
We do not know. This is an open question, not a solved one, and anyone who tells you otherwise is selling something.
But the balance of the clues has shifted in a way that would have shocked a physicist a century ago. Information is no longer a bookkeeping device we sprinkle on top of “real stuff.” It has a heat cost (Landauer). It obeys strict bounds tied to geometry (Bekenstein). It appears to determine how much reality can fit in a region (holography). And it may be the very thread out of which space is sewn (entanglement and “It from Qubit”).
None of that proves reality is made of information. What it shows is that the old hierarchy, matter first, information second, is no longer obviously correct. At the frontier, matter and information look less like two different things and more like two views of one thing. The question the article started with, which sounded almost like mysticism, has quietly become one of the most concrete research programs in theoretical physics.
Maybe reality isn’t made of stuff. Maybe it isn’t made of information either. Maybe “made of” is the wrong question, a leftover habit from a world of tables and chairs that the universe never promised to respect.
But if I had to bet, I’d bet with Wheeler. And I’d add one letter.
It from Qubit.
Appendix — Landauer’s principle in one page
The claim. Erasing one bit of information in a system at temperature T dissipates at least
E_min = k · T · ln(2)
of energy as heat into the environment. Here k ≈ 1.38 × 10⁻²³ J/K is Boltzmann’s constant. At room temperature this is a tiny number (about 3 × 10⁻²¹ joules), but it is not zero, and it is unavoidable.
Why is there a minimum? The key insight is the difference between reversible and irreversible operations.
- Some logical operations are reversible: from the output you can reconstruct the input. In principle these cost no energy.
- Erasure is irreversible. “Set this bit to 0” maps two possible starting states (0 and 1) onto one ending state (0). Information about where you started is destroyed.
The second law of thermodynamics forbids you from simply making entropy disappear. When you erase the bit, the logical entropy you removed from the memory (ln 2 per bit, in the right units) cannot vanish, it must be pushed out into the environment as thermal entropy, which means heat. That heat is k T ln 2.
Maxwell’s demon, finally exorcised. For a century, physicists were haunted by “Maxwell’s demon”, a hypothetical creature that sorts fast and slow molecules to seemingly violate the second law using only information. Landauer’s principle is the resolution: the demon has to store the information it gathers, and eventually it must erase its memory to keep working. That erasure dumps exactly enough heat to save the second law. Information processing has a thermodynamic price, and the books always balance.
Why it matters for this article. Landauer’s principle is the cleanest demonstration that information is not a ghost. Manipulating bits, purely “abstract” logical acts, has hard physical consequences measured in joules and kelvins. It is the bridge that lets us take seriously the idea that information belongs in the foundations of physics, and not merely in our notebooks about it.
Further reading, if this lit a fire in you: J. A. Wheeler, “Information, Physics, Quantum: The Search for Links” (1989); R. Landauer, “Irreversibility and Heat Generation in the Computing Process” (1961); J. Bekenstein, “Information in the Holographic Universe” (Scientific American, 2003); and for the modern spacetime-from-entanglement story, M. Van Raamsdonk, “Building up spacetime with quantum entanglement” (2010).