The Veil over Unity
(or the physics of Non-locality & Non-duality)
Let’s start with something we think we understand: light. That’s where we left off in our last article about Light, Space and Time.
You know from high school that light behaves like a wave. When you shine light through two narrow slits, you don’t get two bright lines on the screen behind them. Instead, you get an interference pattern. Bright and dark bands, spreading out from where you’d expect just two spots. This happens because light from the two slits interferes with itself, just like water waves do when they pass through two openings in a barrier.
The bright bands appear where the waves from both slits arrive in phase, reinforcing each other. The dark bands appear where they arrive out of phase, canceling each other out. Wave behavior, pure and simple.
Now here’s where it gets interesting. Do the same experiment with electrons. Fire them one by one at two slits. What happens?
You might think: electrons are particles, little balls with charge. They should go through one slit or the other, and you should get two clumps on the screen, one behind each slit. But that’s not what happens.
Fire one electron. It hits the screen. Mark where it landed. Fire another. Mark that spot too. Keep going. Fire thousands of electrons, one at a time, waiting between each one so there’s never more than a single electron in the apparatus at once.
Slowly, gradually, an interference pattern emerges. The same bright and dark bands you get with light. Each individual electron hits at one definite spot, like a particle. But collectively, the pattern they form is exactly what you’d expect from a wave passing through both slits and interfering with itself.
This is deeply weird. Each electron is alone in the apparatus. It can’t be interfering with other electrons. So what’s interfering with what?
You might say, “Well, light does this too.” And you’d be right. But here’s the thing: we understand light as a wave. It makes sense that a wave would create an interference pattern. But electrons? We think of them as particles. How can a single particle create a wave pattern?
The answer gets even stranger when you make the light dim enough. You can set up the double-slit experiment with such weak light that only one photon passes through at a time. And just like electrons, you see them arrive one by one, each hitting at a single spot. But build up enough detections, and the interference pattern appears. You can watch Looking Glass Universe’s video on this topic, and read about the single-photon experiment in this paper.
So light and electrons behave exactly the same way. Each arrives as a localized “chunk” at one spot. But the pattern they collectively form is a wave pattern, requiring interference from both slits.
This is what physicists mean by wave-particle duality. We say quantum objects “travel as waves but exchange energy as particles.” The wave describes where they can go, giving probabilities for different locations. But when they arrive, when they interact with a detector or screen, they do so at one definite spot, transferring a quantized chunk of energy.
Wave-particle duality is real. Quantum objects, whether photons or electrons, exhibit both wave-like propagation (creating interference patterns) and particle-like detection (arriving at definite locations). They “travel as a wave” through space, but “exchange energy as a packet” when measured. Whatever that means.
When Separation Breaks Down
So we have wave-particle duality. Strange, but maybe we can live with it. Electrons and photons are tiny. Maybe the rules are just different down there. Maybe they’re some kind of fuzzy wave-particle hybrid. We can still think of them as individual things, separate from each other, just with weird properties.
But that comfortable picture breaks down completely when we look at entanglement.
Here’s the setup. Create two electrons that have interacted in a special way. Send one to Earth, the other to Mars. They’re now separated by hundreds of millions of kilometers. Now measure a property of the Earth electron, say its spin along some axis. You get a result: up or down.
Immediately, without any delay, the Mars electron’s spin becomes correlated with your measurement. If you measure the Earth electron’s spin along the same axis, you’ll find the Mars electron has the opposite value. Every single time.
You might say: “So what? They decided their spins when they were created. The Earth electron was always going to be spin-up, and the Mars electron was always going to be spin-down. We just didn’t know it yet.”
That was Einstein’s hope. He thought there must be “hidden variables,” properties the electrons carry with them that determine what result you’ll get when you measure. Like a pair of gloves in separate boxes. Open one box, find a left glove, and you instantly know the other box contains a right glove. No mystery. No faster-than-light communication. Just pre-existing properties.
But in 1964, John Bell proved that’s impossible. He showed that if hidden variables existed, measurements at different angles would have to obey certain statistical limits, what we now call Bell inequalities. Then he showed that quantum mechanics predicts violations of these limits. The correlations are too strong to be explained by any pre-existing local properties.
The experiments have been done. Over and over, with increasing precision. The results are clear: Bell inequalities are violated. The electrons don’t have definite spins until you measure them. And when you measure one, the other “knows” instantly, regardless of the distance between them. Watch Veritasium and Mithuna’s video on entanglement to understand this better.
This isn’t communication. You can’t send information this way. The person on Mars sees random results until they compare notes with you. But the correlations are real and instantaneous. Stronger than anything local hidden variables could produce.
Here’s another way to see that reality is non-local. It’s called the Aharonov-Bohm effect, and I think it’s even more striking.
Take an infinitely long coil of wire and run a current through it. A magnetic field will be generated inside it, with none present outside. Sealed off from the outside world.
Now split an electron beam and send it around this wire, through the region where there’s no field. What happens? If fields are what affect particles, and the field is zero where the electron travels, nothing should happen. The electron should behave exactly as if the coil wasn’t there.
But that’s not what you observe. The electron’s path is affected. It accumulates a phase shift. Not because it’s passing through a magnetic field (it isn’t), but because of something called the magnetic vector potential that exists in the space around the coiled column.
You could say the potential is “more real” than the field. But there’s a deeper way to understand this. The electron doesn’t take a single path. It explores every possible path simultaneously. All of them contribute to the final result. The electron is non-locally spread out over all possible trajectories at once.
This is what Richard Feynman’s path integral formulation of quantum mechanics tells us. The electron doesn’t go “here” or “there.” It goes everywhere it could possibly go, all at once. The different paths interfere with each other, just like in the double-slit experiment. And the magnetic potential affects the phase of each path, changing the interference pattern even though no path passes through a region with a magnetic field.
You can see a beautiful explanation of this in Veritasium’s recent video on the Aharonov-Bohm effect, which goes into detail about the advanced experiments done to rule out leaking magnetific fields by generating magnetic fields inside a torus.
Both of these experiments, Bell’s and Aharonov-Bohm’s, are telling us the same thing. The picture of reality as made of separate, localized particles, each with definite properties, existing in definite places, is wrong. At the fundamental level, quantum objects are non-local. They can’t be thought of as separate “things” with independent existence.
When two electrons are entangled, they’re not two separate particles that happen to have correlated properties. They’re a single quantum state, a unified whole. Measuring one “here” and finding a result tells you about what you’ll find “there” not because information traveled between them, but because there’s only one quantum state spanning both locations.
The electron going around the coil isn’t a localized particle following one path. It’s a quantum field exploring all paths simultaneously and instantaneously. The interference between these paths is what determines where the electron ends up.
Reality at the quantum level is non-local, hence non-dual. What we think of as “separate particles” is a misleading picture. The fundamental description is a unitary quantum field, with correlations and interference patterns that span across space. The universe, at its deepest level, is one.
How the One Becomes Many
So if reality is fundamentally non-dual and non-local, why does the world appear so definitively dual and local? Why do I see separate objects in definite places? Why does my chair stay over there, and not quantum tunnel through the floor? How does the unified quantum field give rise to the classical world of distinct, separate things?
The answer lies in a process called decoherence.
Let me show you with a puzzle that bothered physicists in the early days of quantum mechanics. It’s called Mott’s problem, and it beautifully illustrates how duality emerges from non-duality.
When a radioactive atom decays, it spits out an alpha particle (a helium nucleus). According to quantum mechanics, this alpha particle emerges as a spherical wave, spreading out equally in all directions from the nucleus. It has no definite direction of travel. It’s equally likely to go left, right, up, down, or anywhere in between.
Now place this radioactive source inside a cloud chamber, a device filled with supersaturated vapor. When a charged particle passes through, it ionizes atoms along its path, and tiny droplets condense around these ions, making the particle’s track visible.
Here’s the puzzle: if the alpha particle is a spherical wave with no definite direction, why do we see a single, perfectly straight track in the cloud chamber? Shouldn’t the wave randomly ionize atoms throughout the entire chamber, creating a fuzzy cloud rather than a line?
This bothered Einstein and other physicists deeply. In 1929, Nevill Mott solved it, and his solution is considered the first example of decoherence theory.
The key insight: you can’t think about just the alpha particle alone. You have to consider the alpha particle plus all the atoms in the cloud chamber as one unified quantum system.
When Mott did the calculation, he found something remarkable. Yes, the alpha particle starts as a spherical wave. But as soon as it ionizes the first atom, the quantum state of the entire system (particle plus that atom) becomes entangled. This entanglement makes it overwhelmingly more probable that the next ionization will happen nearby, along a straight line from the first one.
Each successive ionization reinforces this pattern. Not because the alpha particle is “really” traveling in a straight line, but because the entanglement between the particle and the environment (the cloud chamber atoms) causes the different possible directions to decohere. They stop interfering with each other.
The spherical wave doesn’t collapse into one direction. It evolves into a superposition of many different straight-line possibilities, but these possibilities no longer interfere.
You can explore this in detail in this excellent video by Action Lab on Mott’s problem and decoherence.
This is how the classical world emerges from quantum mechanics. Large objects are constantly bombarded by photons, air molecules, and countless other particles. Each interaction entangles the object with its environment. This entanglement washes out the quantum interference effects that would reveal the object’s wave nature. What remains looks classical. Definite. Localized.
Your chair doesn’t quantum tunnel through the floor not because it’s “too big” for quantum mechanics, but because it’s constantly decohering due to interactions with the environment. The different possible positions it could tunnel to stop interfering with each other almost immediately.
Decoherence explains why things clump into stable, non-interfering chunks. Why we see definite outcomes rather than fuzzy superpositions. It’s the bridge between the non-dual quantum world and the dual classical world we experience.
But here’s what decoherence doesn’t explain: why this particular outcome?
In the cloud chamber, decoherence explains why we see a straight track rather than a fuzzy cloud. But it doesn’t tell us why the track goes in this direction rather than that one. The spherical wave contained all possible directions. Decoherence separates these possibilities into non-interfering branches. But which branch do we experience?
That’s where the Born rule comes in. The Born rule says the probability of observing a particular outcome is given by the square of the wave function’s amplitude. Where the wave is strong, you’re more likely to see that outcome. Where it’s weak, you’re less likely.
But the Born rule only gives probabilities. It doesn’t tell us which specific outcome will occur. That appears to be fundamentally random. Not random because we lack information (Bell’s theorem ruled out hidden variables, remember). But random in a deeper sense.
The universe doesn’t “decide” which outcome will happen until it happens. The selection of one particular track direction out of all possible directions is not determined by anything. It just happens. Probabilistically.
This is the deepest mystery. We can describe with perfect precision how the non-dual quantum field evolves. We can calculate exactly how it decoheres into separate, non-interfering branches when it interacts with an environment. We can predict the probabilities for different outcomes with stunning accuracy.
But why one particular outcome manifests out of the many possibilities, we cannot say. That transition, from the superposition of all possibilities to the actuality of one, remains fundamentally mysterious.
Decoherence explains how the unified quantum field appears as separate, classical objects through interaction with the environment. But the selection of which particular outcome we observe, from among all the quantum possibilities, follows only probabilistic rules (Born’s rule). Why this randomness exists, why one specific outcome manifests rather than another, is not explained by the theory. This is the bridge between non-duality and duality, and it remains deeply mysterious.
The Veil of Maya
If you’ve studied Advaitic philosophies like Vedanta or Trika, what I’ve just described might sound strangely familiar. The ultimate reality is seen as Brahman or Shiva. The Vast. The Infinite. A-dvaita literally translates to Not-two. So this vast universe is not really separable, as we see when we go down to the smallest “particles”.
What we perceive as the world of separate objects, distinct identities, individual locations, all of this is Maya. Not illusion exactly, but a kind of appearance, a superimposition on the non-dual ground of being.
In Advaita, the question “why does the One appear as many?” is considered ultimately unanswerable. It’s the nature of Maya to veil the non-dual reality and project the appearance of multiplicity. How this happens, why it happens, cannot be fully explained. It’s the inexplicable power of Brahman to appear as the world.
In quantum mechanics, the question “why does measurement select one particular outcome from the superposition?” is also unanswerable. It’s the nature of quantum measurement, described by the Born rule, to produce definite results from indefinite possibilities. The randomness is fundamental, not a placeholder for hidden ignorance. Why the probabilities “collapse” the way they do remains a mystery.
Trika sees the underlying reality of Shiva as vibrating with Shakti (energy). Just like the particles we perceive as separate are wave-like vibrations of the underlying field, a chunk of minimum viable quanta of energy.
🪷 All is Unfolding 🪷
The multiplicity, the separation, the definite positions of distinct objects, all arise within the underlying One. How they arise, why one possibility manifests rather than another, why this thought appears now, why that electron hit this spot instead of that one, these questions may have answers but they are veiled from us.
But we can face the veil. Not by explaining it away, but by recognizing its nature as that non duality. By not binding our self-identification to the mere particles that make up our body and mind. By aligning ourselves with the universe’s flow. Because ultimately, You are That.
Here’s a verse from Japji Sahib to close this up:
हुकमी हुकम चलाइ राहु ।
नानक विगसै वेपरवाहु ।।
Hukami Hukam Chalaye Rahu,
Nanak Vigasai Veparvahu
The willer is willing,
(Nanak says) blossoming, without care.