Quantum entanglement is a link between two or more particles that share a single quantum state, so that measurements on them give correlated results no matter how far apart they are. Each individual result is random, and the pattern only appears when the two sets of results are compared. Those correlations are stronger than any explanation in which each particle simply carries pre-set instructions, which is why physicists treat entanglement as a genuinely non-classical feature of nature.
It matters because entanglement sits at the center of two conversations. In physics it underpins quantum cryptography, quantum computing and the 2022 Nobel Prize. In popular spirituality it is borrowed to explain telepathy, prayer and the idea that everything is connected. Knowing what the experiments have established, and what they have not, is the starting point for the holographic universe topic hub and for reading any claim that uses the word "quantum."
What is quantum entanglement, in plain terms?
Quantum entanglement means two particles are described by one shared state rather than two separate ones, such as a pair of photons created together with linked polarizations. In standard quantum mechanics, neither photon is assigned a definite polarization before measurement. When both are measured along the same direction, the results line up in a fixed way every time, even if the photons are kilometers apart.
The important detail is that each side, on its own, sees nothing unusual: each experimenter records a random string of outcomes, like coin flips. Only when the two lists are compared does the correlation show up.
A pair of gloves in two boxes is the usual comparison: open one box and you know what is in the other. But with gloves the answer was fixed when the boxes were packed. With entangled particles, the strength of the correlations across different measurement angles cannot be reproduced by any pre-packed answer, and that difference is exactly what John Bell found a way to test.
Where did the idea come from? EPR, Schrödinger and "spooky action"
The idea came from a challenge to quantum mechanics, not a celebration of it. In May 1935 Albert Einstein, Boris Podolsky and Nathan Rosen published "Can Quantum-Mechanical Description of Physical Reality Be Considered Complete?" in Physical Review, volume 47, page 777. Their argument, now called EPR, considered two particles that had interacted and separated. If measuring one lets you predict the other's result with certainty, they argued, the distant particle must already possess that property; since quantum mechanics did not assign it in advance, the theory was incomplete.
Niels Bohr replied in the same journal later in 1935, under the same title, arguing that the EPR reasoning misread the role of the measurement context in quantum physics.
Erwin Schrödinger took up the problem the same year. In a letter to Einstein he used the German word Verschränkung, and in a 1935 paper for the Cambridge Philosophical Society he introduced the English term "entanglement," calling it the characteristic trait of quantum mechanics rather than a side issue.
In a later letter to Max Born, dated 3 March 1947, Einstein objected to "spukhafte Fernwirkung," usually translated "spooky action at a distance." In 1951 David Bohm, in his textbook Quantum Theory, recast the EPR argument using particle spin, with simple yes-or-no outcomes.
It is not accurate to say Einstein was simply proven wrong. His insistence that the theory be pressed on exactly this point is what led to Bell's theorem and every experiment that followed.
What did Bell's theorem show?
Bell's theorem showed that the EPR debate could be settled by experiment. John Stewart Bell, a physicist born in Belfast in 1928 who worked at CERN in Geneva, published "On the Einstein Podolsky Rosen Paradox" in the journal Physics (volume 1, page 195) in 1964.
Bell asked what would follow if each particle carried hidden instructions fixed at the source and nothing done at one detector could affect the other (locality). He proved that any such "local hidden-variable" theory must keep the correlations between distant measurements below a mathematical limit, now called a Bell inequality. Quantum mechanics predicts that, for certain measurement angles, entangled particles break that limit.
That turned a philosophical argument into a measurable number. In 1969 John Clauser, Michael Horne, Abner Shimony and Richard Holt published a version suited to real laboratory equipment, known as the CHSH inequality, in Physical Review Letters. Most Bell tests since have used it or a close relative.
How did experiments test entanglement?
The experiments sided with quantum mechanics, and each generation closed another gap. In 1972 Stuart Freedman and John Clauser at the University of California, Berkeley, used calcium atoms that emitted pairs of entangled photons and recorded a clear violation of a Bell inequality.
A remaining worry was that fixed detector settings might let some unknown signal coordinate the two sides. Alain Aspect and colleagues at the Institut d'Optique in Orsay, France, addressed this in experiments published in 1981 and 1982. In the best-known run, the measurement settings were switched while the photons were already in flight, too fast for any signal at light speed to pass between the stations. The violation remained.
Anton Zeilinger's group in Innsbruck and later Vienna refined these tests and turned entanglement into a tool. In 1997 the Innsbruck team, in a Nature paper first-authored by Dik Bouwmeester, demonstrated quantum teleportation: the quantum state of one photon was transferred to another photon at a distance, using entanglement plus an ordinary classical signal. In 1998 the group added entanglement swapping, entangling two photons that had never met.
In 2015 three teams reported "loophole-free" Bell tests that closed the main gaps at once. At Delft University of Technology, Ronald Hanson's group entangled electron spins in two diamonds 1.3 km apart. A Vienna team and a team at the National Institute of Standards and Technology (NIST) in Boulder, Colorado, did the same with photons, using highly efficient detectors and random setting choices made while the photons travelled.
Entanglement has also been taken into space. In 2017 a Chinese team led by Juan Yin and Jian-Wei Pan used the Micius satellite to send entangled photons to two ground stations 1,203 km apart and still measured a Bell violation.
Why did the 2022 Nobel Prize go to Aspect, Clauser and Zeilinger?
On 4 October 2022 the Royal Swedish Academy of Sciences awarded the Nobel Prize in Physics in equal shares to Alain Aspect, John F. Clauser and Anton Zeilinger "for experiments with entangled photons, establishing the violation of Bell inequalities and pioneering quantum information science."
The citation has two halves: their experiments, from Berkeley in the 1970s through Orsay to Innsbruck and Vienna, established that nature violates Bell inequalities, and that work became the basis of a new engineering field. The prize was not for teleporting objects or people, nor for faster-than-light signaling. It was for showing, with increasing rigor, that entangled correlations cannot be explained by local hidden instructions.
What can quantum entanglement not do?
Quantum entanglement cannot be used to send a message, faster than light or otherwise. Because each local outcome is random, the person at one end cannot choose what the person at the other end will see. The no-communication theorem in quantum information theory makes this precise: nothing done to one half of an entangled pair changes the statistics observed at the other half on its own. The correlation exists, but it can only be read by comparing records, and that comparison travels by ordinary means.
This is why entanglement does not conflict with Einstein's relativity, and why popular descriptions of one particle reaching out to alter its partner are misleading. A more careful statement is that the outcomes are correlated in a way no local, pre-set mechanism can explain. How to describe what is "really" happening is a matter for interpretations of quantum mechanics, which disagree.
Quantum teleportation fits the same rule. It transfers a quantum state, not matter, destroying the original, and the receiver cannot complete it until a classical message, limited by the speed of light, arrives.
Entanglement is also fragile. When entangled particles interact with their surroundings, the entanglement spreads into the environment and is effectively lost, a process called decoherence. That is why laboratory entanglement depends on carefully isolated systems such as single photons, trapped ions, superconducting circuits near absolute zero or defects in diamond.
What is entanglement used for today?
Entanglement is used today in three main areas. Quantum key distribution shares encryption keys in a way that reveals any eavesdropper. Quantum computers rely on entanglement among qubits for calculations ordinary computers cannot efficiently simulate. Quantum networks, built on teleportation and entanglement swapping, aim to link such devices over long distances.
On the theoretical frontier, entanglement has become a candidate building block of space and time. In 2013 Juan Maldacena and Leonard Susskind proposed "ER=EPR," the conjecture that entangled particles (EPR pairs) are connected by Einstein-Rosen bridges, the wormholes described in a separate 1935 paper by Einstein and Rosen. It is a research hypothesis, not an established result, and it ties into the holographic principle, where, in some theoretical models, the geometry of a region of space is encoded in the entanglement of quantum information on its boundary.
How the word "quantum" gets misused
The word "quantum" is often borrowed for claims physics does not make. The physicist Murray Gell-Mann, in his 1994 book The Quark and the Jaguar, called this kind of borrowing "quantum flapdoodle."
Statements that entanglement links human minds, carries intention or prayer, lets DNA connect with the universe, or proves that everything is one are spiritual or metaphorical readings. They may be meaningful as philosophy or practice, but no experiment has shown them. Bell tests use particles isolated with great care; brains are warm, wet and constantly interacting with their environment, the conditions under which decoherence destroys entanglement fastest.
A related confusion concerns the "observer," which in quantum mechanics means any physical interaction that records a result, with or without anyone watching. The double-slit experiment explainer covers why that does not by itself show that consciousness creates reality.
Billy Carson's reading
Billy Carson uses entanglement as a model for questions physics leaves open. In his short clip "Quantum Entanglement and Prayer," embedded with this article, and in his 2019 podcast episode The Power of DNA and How to Quantum Entangle with the Universal Consciousness, he asks whether minds might be connected non-locally the way particles are, and whether prayer and intention could work through that kind of connection to a universal consciousness. That is his spiritual reading of the physics. The experiments above concern photons, electrons and atoms; they neither test nor support it.
His earlier explainer on the site, The Intriguing Phenomenon of Quantum Entanglement Unraveled, keeps one line of the physics clear: it states that "entanglement does not enable the transmission of useful information, adhering to the limitations of relativity." That is the same boundary the no-communication theorem draws.
Carson also uses "entangled" as an everyday metaphor. In his talk You Can't Manifest When You're Entangled in Someone Else's Karma, being entangled means leaking attention and energy into gossip, emotional triggers and other people's drama. He describes "every thought, every conversation, and every scroll" as "an energetical transaction" and recommends an energy audit of where a day's attention goes. There the word is an image for focus and boundaries, not a statement about particle physics. The related question of whether reality is fundamentally informational is explored in Simulation Theory Explained.
Watch, read and go deeper
Billy's clip on entanglement and prayer is embedded with this article, and his full conversation on DNA and universal consciousness is on the 4biddenknowledge Podcast. Every related article and video is gathered on the holographic universe topic hub.
Frequently asked questions
Can quantum entanglement be used to communicate faster than light?
No. Each measurement result at one end is random, so neither side can control what the other sees, and the correlation only appears when the two records are compared through an ordinary channel. The no-communication theorem shows that entanglement alone cannot carry a message at any speed.
Did the 2022 Nobel Prize prove Einstein wrong?
Not in a simple sense. The laureates showed that nature violates Bell inequalities, ruling out the local hidden-variable picture Einstein preferred. But Einstein's 1935 challenge with Podolsky and Rosen is what led Bell to devise the test.
What is Bell's theorem in simple terms?
Bell's theorem, published by John Stewart Bell in 1964, says that if particles carried pre-set answers and nothing travelled between distant detectors, their correlations could never exceed a certain limit. Quantum mechanics predicts that entangled particles exceed it, and experiments since 1972 have confirmed that they do.
Is quantum teleportation the same as teleporting matter?
No. Quantum teleportation transfers the quantum state of one particle onto another particle already at the destination, and the original state is destroyed. It requires a classical signal, so it cannot work faster than light, and no matter travels between the two locations.
Does entanglement prove that human minds are connected?
No experiment has shown entanglement between human minds, and the warm, noisy brain is where entanglement is hardest to maintain. Ideas that it explains telepathy, prayer or manifestation are spiritual readings, not results of physics.
Sources and further reading
- A. Einstein, B. Podolsky and N. Rosen, "Can Quantum-Mechanical Description of Physical Reality Be Considered Complete?" Physical Review 47 (1935), and Niels Bohr's reply, Physical Review 48 (1935)
- E. Schrödinger, "Discussion of Probability Relations between Separated Systems," Proceedings of the Cambridge Philosophical Society 31 (1935)
- J. S. Bell, Speakable and Unspeakable in Quantum Mechanics (collected papers, including the 1964 Bell theorem paper)
- J. F. Clauser, M. A. Horne, A. Shimony and R. A. Holt, Physical Review Letters 23 (1969); S. J. Freedman and J. F. Clauser, Physical Review Letters 28 (1972)
- A. Aspect, J. Dalibard and G. Roger, "Experimental Test of Bell's Inequalities Using Time-Varying Analyzers," Physical Review Letters 49 (1982)
- D. Bouwmeester et al., "Experimental Quantum Teleportation," Nature 390 (1997); B. Hensen et al., Nature 526 (2015)
- Nobel Committee for Physics, background material on the Nobel Prize in Physics 2022, and Murray Gell-Mann, The Quark and the Jaguar (1994)
