main tags laws scientists sections authors graph theory
Popular

superposition principleprinciple

# tag · @ author · ! scientist
30 Related articles
A quantum particle can be in several states at once — like a coin tossed in the air, which hasn't landed yet and so is neither heads nor tails, but a mixture of them. This cocktail of possibilities collapses into a concrete result only upon measurement.

How it works

All of quantum chemistry (formation of molecules), the operation of quantum computers, and quantum cryptography are based on superposition. For example, the hydrogen molecule arises because the electron 'splits' itself between two protons.

💡 The most famous example of superposition is Schrödinger's cat: in a thought experiment, it sits in a box with a poison mechanism and is simultaneously alive and dead until you open the lid.
|\psi\rangle = c_1|\psi_1\rangle + c_2|\psi_2\rangle
|ψ⟩ is the quantum state vector, |ψ_1⟩ and |ψ_2⟩ are basis states (e.g., spin up/down), c_1 and c_2 are complex probability amplitudes, normalized by the condition |c_1|^2 + |c_2|^2 = 1.
P(|\psi_i\rangle) = |c_i|^2
P(|ψ_i⟩) is the probability of finding the system in state |ψ_i⟩ upon measurement, c_i is the corresponding probability amplitude; the sum of probabilities of all possible outcomes equals 1 (normalization condition).
Links in the knowledge graph 1
Discovered by
David DeutschErwin SchrödingerJohn Stewart BellLouis de BroglieLov GroverPaul Benioff
Related concepts
Hilbert spaceinterferometerNeutrino oscillationquantum algorithmquantum decoherencequbitsuperpositionVLBI
Related laws
Schrödinger equationHeisenberg uncertainty principle

Related articles

The Skyrmion Dance: How a Magnetic Vortex Conducts the Quantum Orchestra

A hybrid quantum system has been proposed, combining long-lived spin memory, a fast superconducting processor, and a topologically protected mediator — a magnetic skyrmion. Its oscillations bridge the atomic world of defects with macroscopic circuits, overcoming the scale chasm. Calculations promise
arXiv:2505.00266v1 · 2025-05-01

Quantum Debts: When a Photon Has Negative Presence

For the first time, physicists operationally measured how a single photon physically distributes between two paths of an interferometer. It turned out that in the port with destructive interference, 'superlocalization' occurs: the probability of presence in one arm exceeds unity, while in the other
arXiv:2505.00336v2 · 2025-05-01

Symphony of Imaginary Frequencies: Quantum Decay of the Inverted Well

A classical particle rolls off a hilltop, nudged by gravity; its quantum twin is pushed down by the uncertainty principle itself. A new work provides a rigorous solution for the inverted potential well: energy becomes purely imaginary, E = iℏω(n+½), and states decay exponentially. Yet in coherent su
arXiv:2505.00475v2 · 2025-05-01

Light in a Cryostat: How Imperfect Converters Build Quantum Bridges

Superconducting quantum computers hit a cooling wall: a single cryostat can't hold millions of qubits. The solution is optical channels, but they need microwave-to-optical converters, which are still far from perfect. The authors showed that with feedback protocols, parallel attempts, and quantum di
arXiv:2505.00542v1 · 2025-05-01

Quantum Measurement as a Deformation of Perception: The Bloch Sphere and the Birth of Categories

A deep connection between quantum measurement and categorical perception: how a continuous spectrum turns into discrete concepts. On the Bloch sphere, wave function collapse deforms distances—pure states 'fall' into mixed ones, distances within a category shrink, and those between categories stretch
arXiv:2505.00777v1 · 2025-05-01

Dance of the Octopus Electron: What Quantum Tunneling Says About the Nature of Reality

Quantum tunneling is not just a trick that lets electrons seep through impassable barriers. It’s a window into the deepest mysteries of reality. It turns out that an electron behaves not as a point, but as a distributed entity—something like an octopus squeezing its tentacles through a crack. This v
arXiv:2505.00872v4 · 2025-05-01

Maximum Quantum Entanglement: Hidden Symmetry and the Mirror Universe

Researchers found that if Higgs particle collisions are required to always produce maximally entangled states, the Higgs potential automatically extends its global symmetry. This leads to an exact symmetry U(2)×U(2), spontaneously broken to U(1)×U(1), giving rise to six massless Goldstone bosons. A
arXiv:2505.00873v1 · 2025-05-01

Quantum Symphony from Noise: How Spontaneous Emission Gives Birth to Entanglement

Contrary to the entrenched view of spontaneous emission as an incoherent process that destroys quantum entanglement, a team of physicists has theoretically demonstrated the possibility of generating near-perfect bipartite entanglement between two bright light fields. The scheme is based on a four-le
arXiv:2505.00919v1 · 2025-05-01

Quantum Tuning Fork: Noise Speeds Up the Search for Single Emitters

Brute-force photon counting from a single emitter gets bogged down in noise, like digging a tunnel with a shovel. But introduce a coherent reference beam and let quantum interference kick in — and the picture changes dramatically: the noisier the environment, the faster the verdict. The extended Hon
arXiv:2505.00950v2 · 2025-05-02

Death and Rebirth of Quantum Echo: A Hierarchy of Temporal Correlations in a Qubit

Physicists made a superconducting qubit forget its past—and saw how three types of temporal correlations (non-macrorealism, temporal steering, temporal non-separability) arrange themselves into a logical ladder. These echoes die at different noise levels and can resurrect when the environment briefl
arXiv:2505.01379v1 · 2025-05-02

The Rydberg Waltz: How a Dance of Losses Amplifies Quantum Sensitivity

Quantum sensors based on Rydberg atoms can detect minuscule electromagnetic fields, but optical readout usually destroys almost all signal photons. Physicists from Warsaw went against the grain and deliberately enhanced nonlinear losses through dipole-dipole collisions of excitations. This paradoxic
arXiv:2505.01506v2 · 2025-05-02

Radical Dance, Frozen by Chirality: How Birds See the Magnetic Field

The work shows how chirality—the property of a molecule not coinciding with its mirror image—turns a weak magnetic signal into a reliable compass. Chirality does not merely create quantum coherence, but induces spin polarization, forcing the system to endlessly 'freeze' in one state. This amplificat
arXiv:2505.01519v1 · 2025-05-02

Quantum Boomerang: Fugue in a Detuned Orchestra

Disordered quantum systems usually stifle any transport, but new simulations have revealed a quantum boomerang: in a discrete walk, the wave packet returns, only not to the starting point, but to the opposite end. The internal state of the coin particle creates an asymmetry without external force—li
arXiv:2505.01532v1 · 2025-05-02

A Glass Loom for Light: 99.7% Fidelity Across 24 Quantum Threads

Researchers from Ephos and the Polytechnic University of Milan inscribed a 24-mode universal photonic processor into glass, using femtosecond lasers like a sewing machine needle. Operating at 925 nm—ideal for quantum-dot single-photon sources—the device is controlled by microheaters and uses less po
arXiv:2505.01609v2 · 2025-05-02

Seven Lives of a Photon: Exceptional Points Control Spontaneous Emission

By combining lithium niobate and gallium arsenide, scientists created a chip. In it, quantum dots interact with microresonator modes, and electro-optic tuning of the feedback phase drives the system to an exceptional point. At this singularity, two modes coalesce, and the spectral density of states
arXiv:2505.05490v1 · 2025-05-02

Quantum Wallet: Energy Teleportation Between Five Qubits

Imagine a shared wallet: one person deposits their paycheck, and the others take turns withdrawing, with the first grabbing the largest bill. In the quantum world, this is how energy teleportation works in a W state — a special kind of multipartite entanglement. Experiment on the IBM Lagos processor
arXiv:2505.01863v1 · 2025-05-03

Quantum Ghosts in the Hall of Mirrors

Usually, nonclassical states of motion require clever tricks. But new research reveals that the intrinsic nonlinearity of an optical trap itself sculpts quantum 'ghosts' from mechanical vibrations — states with a negative Wigner function. No probabilistic schemes needed, even in unresolved sidebands
arXiv:2505.01942v2 · 2025-05-03

Conductor of Heat Death: The Charge Palette of a Quantum Bath

The Mpemba effect, familiar from the paradoxical behavior of water, gains a quantum dimension: in isolated systems, a more non-equilibrium state sometimes relaxes faster. New research reveals the mechanism — the key lies in the symmetry structure of the thermostat's initial state. The wider the ener
arXiv:2505.02040v2 · 2025-05-04

Quantum Internet: How Entanglement Became a Data Packet

Superconducting qubits and optical photons are separated by a five-order-of-magnitude frequency gap. Direct qubit translation is an engineering dead end, but an architectural trick inspired by packet switching turns weak transducers into entanglement generators. Thus the quantum internet transforms
arXiv:2505.02057v4 · 2025-05-04

Gravitational Duet: How Entangled Masses Listen to the Whisper of Other Dimensions

Extra dimensions have long evaded detection due to electromagnetic noise. The protocol of quantum-induced entanglement of masses turns two microscopic bodies in superposition into gravitational tuning forks, accumulating a phase shift exquisitely sensitive to deviations from Newton's law. Analysis o
arXiv:2605.00749v1 · 2026-05-01

The Black Hole's Spin Signature: Polarization Ripples on Its Shadow

New research reveals a subtle mechanism: polarization doesn't just illuminate a black hole's shadow — it deforms it. The effect, predicted for rotating holes, is vanishingly small but fundamental: polarimetry transforms from a passive spectator into an active probe of extreme gravity. In a static sc
arXiv:2605.02136v2 · 2026-05-04

Phantom Chords of Gravity: Boson Stars as Keepers of Quantum Memory

Quantum systems typically evolve toward equilibrium, losing all memory of their initial state. But occasionally, 'scars' are born — anomalously stable, weakly entangled states that challenge thermalization. New research shows that boson stars in anti-de Sitter space realize such scars, combining cha
arXiv:2605.02446v2 · 2026-05-04

Squeezed Gravitational Waves: How Quantum Optics Reveals the Voice of Black Holes

Black hole collisions transform the quantum whisper of spacetime into a roar that LIGO detectors can catch. Analysis shows that multi-particle graviton emission organizes into a generalized squeezed coherent state, exponentially amplifying fluctuations. Thanks to the double copy between QCD and grav
arXiv:2605.03038v1 · 2026-05-04

Gravitational Shadows: How Mass Splits Reality

Matter interferometry creates a Schrödinger's cat for macroscopic masses, opening the path to quantum gravity. A mass in superposition generates two clouds of coherent gravitons — gravitational shadows. Their contrast drops exponentially with increasing mass, signaling the growing entanglement betwe
arXiv:2605.05153v1 · 2026-05-06

The Singularity That Never Was: How Quantum Tango Erases the Beginning of the Universe

In quantum cosmology, the Big Bang singularity turns out to be a mirage. Using relational time emerging from entanglement between subsystems of the universe, physicists have shown: the probability of zero volume is strictly zero. The Page-Wootters formalism transforms a static wave function into an
arXiv:2605.06093v1 · 2026-05-07

When Gravity Knits Quantum Lace: Lessons from the Schrödinger–Newton Model

The hybrid Schrödinger–Newton equation for the first time analytically disentangled two faces of gravity: self-interaction and mutual attraction. It turns out that self-gravity does not alter the Schmidt spectrum, and hence the measure of quantum entanglement; however, the pairwise potential activel
arXiv:2605.06577v1 · 2026-05-07

Quantum Tremor of Parallel Worlds: Gravity on a Laboratory Table

A new theoretical work unites quantum mechanics and general relativity, showing that two parallel atomic lasers, unperturbed in the classical world, begin to diverge under the influence of quantum fluctuations of spacetime. Vacuum tremors of the metric give rise to an irreducible spread of trajector
arXiv:2605.11035v1 · 2026-05-11

Cosmic Spinning Top: Gravity vs. Quantum Superpositions

Mass currents have now been introduced into the Diósi–Penrose wave function collapse model for the first time, adding post-Newtonian corrections from general relativity. It turns out that moving mass generates gravitomagnetic noise, causing angular momentum decoherence. The most dramatic effects app
arXiv:2605.12172v1 · 2026-05-12

Graviton Laser: Translating Gravity into the Language of Light

The main obstacle for a graviton laser is that gravitational waves cannot be reflected: they pass through any substance. The solution lies in the Gertsenshtein effect. Under a powerful magnetic field, gravity particles temporarily become photons, which are easily reflected by ordinary mirrors. The r
arXiv:2605.14050v1 · 2026-05-13

A Five-Dimensional Trace in the Cosmic Microwave Background

What lies beyond three dimensions? Theories with extra spatial dimensions predict the birth of massive particles in the young Universe. Using the cosmic microwave background as a kind of 'spectrograph,' scientists analyzed data from the Planck satellite looking for imprints of Kaluza–Klein gravitons
arXiv:2607.02651v1 · 2026-07-02