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An ordinary random network is like a road map: to connect four cities with a complex interchange, you need to lay down many highways. In the quantum world, things are different.

An electrical grid stuffed with power electronics resembles a huge orchestra without a conductor. Each converter, each line adds its own note, and sometimes the instruments start playing out of tune.

A black hole's horizon is not a wall but rather a one-way membrane. Anything that crosses it disappears forever. Stephen Hawking showed that this boundary should glow faintly, emitting particles. But catching such radiation from a real black hole is impossible: it's too far and too dim. Physicists have found a workaround: build a "toy" black hole out of magnetic atoms.

Quantum devices are no longer lab curiosities. They are assembled, tuned, and repaired like ordinary hardware — except inside them, it's not just current but intricate tangles of particles that can exist in multiple states at once. Engineers draw schematics, programmers write code, physicists calculate effects.

The classical neuron is a chamber musician, drawing only one note from each string: it takes a weighted sum of inputs, adds a bias, and passes it through a nonlinearity.

A network of tiny magnets seeks the state with the lowest total energy: that's roughly what the quantum Max Cut problem looks like, one of the toughest in physics. Scientists have been hunting for its solution since the days of Werner Heisenberg.

Strike a tuning fork with a mallet — it vibrates, and the sound gradually fades. A black hole behaves much the same way when disturbed: it emits gravitational waves — ripples in spacetime itself — and then settles down.

The quantum world is full of transformations. Sometimes a system made of one type of particle starts behaving as if it harbors completely different ones. For example, in a chain of bosons, sociable particles that like to crowd into the same state, fermions from the Standard Model may unexpectedly appear, even though they usually keep to themselves.

In the 1990s, philosopher John Searle devised a thought experiment: a person sits in a room and, without knowing Chinese, follows instructions to produce correct answers in Chinese. From the outside, it seems they understand the language, but inside, it's just mechanical rule-following.

Computational studies of material behavior have long suffered from two extremes: either fast but inaccurate models, or accurate but slow physical calculations. Modern programs, trained on data, have nearly resolved this dilemma — now the bottleneck is not computing power, but human routine: setting up simulations and checking results. Paimon works like an autonomous chef.

A quantum computer is like an orchestra: each musician plays their own part, but the slightest noise from the audience can throw off the whole ensemble. The particles that store information easily lose their coherence from thermal jolts or stray magnetic fields.

An eternal Universe where the measure of disorder (энтропия) grows is, for most of its time, a homogeneous void. In it, complex structures occasionally assemble by chance, such as fleeting consciousnesses — ‘мозги Больцмана’.

An old mechanical alarm clock ticks on the shelf. You hear the steady sound, see the hands moving, and you're certain time is passing. But if you take the clock apart, you won't find a single part labeled "time." Only springs and gears.

The quantum world is usually drawn with points, but real instruments only see blurry spots. Heisenberg and von Neumann long suspected: precision is unattainable.

Dip your finger into water once, and from that single sensation, try to guess its temperature. In the quantum world, such one-shot measurements happen all the time, except you have to guess invisible parameters: say, the squeezing strength of a laser beam.

Before assembling a huge puzzle, you need to stamp out the pieces — otherwise the picture won't come together. In fusion-based quantum computers, the role of such pieces is played by tiny clumps of light — photonic resource states. They are collided and measured to gradually grow the computational fabric.

Three craftsmen work in the same workshop. The first tries to figure out whether tiny hourglasses are built into nature's own machinery. The second attaches a laser pointer to a microscope to see details invisible to the naked eye. The third, conversely, takes living threads and carefully weaves them into fragile quantum circuits.

Quantum computers promise to solve problems that regular computers can't. But where is the line? The authors of a new study stumbled upon a surprising case: electrons paired up behave like a well-behaved orchestra. Even if you add a bit of "magic"—a special quantum resource: their behavior remains predictable.

Imagine a line of dominoes: when the first one falls, it pushes its neighbor, and a wave rushes down the chain. The boundary between fallen and standing dominoes is a perfect image of a magnetic wall. In microscopic magnetic films, these walls separate zones with different magnetizations.

A classical computer sorts data like a person meticulously sifting through grains of sand of different colors. A quantum processor takes its cue from nature: just as a droplet of water splits sunlight into a rainbow, revealing all hues at once, this new algorithm instantly grasps the essence of vast information arrays.

The biggest puzzle in physics is how to reconcile spacetime curvature with quantum mechanics. At the Planck length, billions of billions times smaller than an atom, the rules break down. This frontier was discovered by Max Planck.

A three-seat swing never stops: one rider is always left hanging. That’s a frustrated magnet — a perpetual dance with no rest. To study it, physicists built a quantum simulator from 256 atoms, meticulously mimicking the crystal TmMgGaO₄.

Light races through a maze of mirrors and beam splitters, but at the end of its journey, it doesn't just flash on a detector: it transforms itself. In the new photonic computer, nonlinear modules have been added to the familiar linear circuits, and now light can perform any quantum operation, not just a subset.

A regular wall clock runs smoothly, but quantum clocks are a different story. They tick at random moments, and each tick can have a different duration. On average, if you watch such a clock for a long time, it will show the correct time. But at any given moment, its hand might jump forward by an unexpected amount.

In a diamond crystal, a tiny defect sometimes occurs: a nitrogen atom takes the place of a carbon atom, and nearby a lattice site is empty. Electrons in this spot behave like a spinning top that can rotate in different directions. These 'spinning tops' are ready-made cells for future quantum computers and ultra-sensitive sensors.

The magnetic field you want to measure is like a melody played in a noisy hall. A quantum sensor is a microphone that can pick up the faintest notes, but it also hears more than just the music: rustles, creaks, the breathing of neighbors. All of that mixes into the signal and spoils the recording.

Inside every cell, chemical reactions are constantly underway, like a tiny kitchen where protein chefs whip up essential compounds. But seeing exactly how a chef prepares a dish is tricky when you're surrounded by a crowd of other molecules.

A quantum bit, or qubit, is like a coin spinning on a table, able to be both heads and tails at once. For the computer to know what came up, you have to stop the coin and look. Previously, this stopping was done with a delay: data was read out, taken to a regular computer for processing, and only then was the result known.

Inside a tiny crystal, sound is trapped like light in a mirrored room. It bounces off the walls and forms standing waves — a multitude of harmonic oscillations, each with its own frequency. Physicists have learned to use these oscillations as qubits — the basic units of quantum information.

When making popcorn, a microwave uses electricity only to heat the kernels. A gas stove heats the entire burner and the air around it. The same difference applies between a photonic quantum chip and a classical supercomputer when solving a problem devised by Scott Aaronson.

A quantum particle, an inhabitant of the elementary particle world, resembles a coin spinning in the air: neither heads nor tails, but a blend of possibilities. Yet when it lands on the table, the outcome becomes definite. What serves as the table in a measurement?

There's always a risk that someone will peek at your ballot during an election. Physicists have come up with a solution: anonymous voting safeguarded not by people, but by the laws of nature. Their 'magic ballot box' operates with light particles — photons.

We are used to thinking that events have causes, objects exist independently, and signals cannot outpace the speed of light. Quantum mechanics, which describes the Standard Model of particles, challenges all these assumptions at once — as if a recipe couldn't use all seven ingredients.

Turning CO₂ into fuel is like finding the one perfect way to pack billions of items into a suitcase. A classical computer tries options one after another, taking decades, while a quantum computer sees all combinations at once.

The task resembles a giant maze with a single exit among billions of dead ends. A conventional computer checks each corridor step by step — taking centuries. A quantum processor launches a wave that seeps through all paths at once. The correct route echoes back, amplifying, and the answer is found in hours. That’s exactly how the “peak” circuits worked in the new experiment.

Intelligent action begins with a plan. Just as an architect needs blueprints to evaluate options, any agent with will needs to repeatedly copy data about reality.

Time in quantum mechanics is like a shadow on a wall: we see its motion, but we cannot grasp the shadow itself. The Schrödinger equation describes how a system's state changes, but time enters it as an external parameter that nothing measures.

In 1935, Erwin Schrödinger, peering into the equations of quantum mechanics, saw something strange: two particles could be linked so tightly that the state of one instantly determines the state of the other, even if they are separated by kilometers.

In September 2024, the concert hall in Linz had more than just an orchestra on stage. Next to the musicians, a setup was generating pairs of entangled photons: a laser with a wavelength of 405 nm passed through a nonlinear crystal and split into two photons at 810 nm, which flew off to two measurement stations, Alice and Bob.

Two vortex rings launched one after the other pass through each other and swap places. This dance, first seen in the 19th century with smoke rings, has now been reproduced on a quantum processor. Vortices are the actors on a quantum stage where time plays the role of an extra dimension.