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A ship in a bottle is assembled from the inside, not the outside: masts and sails are pulled through the narrow neck, and once inside the glass they settle into the right pose on their own. Chemists have done something similar with a single cobaltocene molecule, which they pulled into the gap between layers of a two-dimensional crystal.

Quantum systems made of many particles are the basis of future computers and secure networks. But the more particles there are, the harder it is to understand how they are arranged: the number of possible states grows like an avalanche. The usual approach, measuring everything, takes an incredibly long time.

A quantum computer isn't just a bunch of qubits: it's a whole city, where each resident is one of the machine's possible states. Residents get to know each other through weak interactions between qubits: if one state can transition to another, a thread of acquaintance is drawn between them.

Quantum computers make mistakes. Each qubit is like a ball balanced on the tip of a pencil: a slight tremor in the hand and it rolls off. To keep the balls from falling, you need someone to notice the wobble and correct it in time.

A cup of hot coffee sometimes freezes faster than cold tap water. This paradox, known as the Mpemba effect, has long been considered a curiosity of classical physics. Now its quantum counterpart has helped test and tune quantum processors — devices that may one day power supercomputers.

A thin silver thread nearly as long as a hair's width, and inside it, pristine quantum laws hold sway. Physicists built a conductor where electrons can only move forward or backward, like on a perfectly straight single-lane road with no shoulders. On such a road, any pothole or pebble would normally destroy the fragile quantum state.

A quantum computer is like an orchestra where each musician-qubit easily loses the rhythm. The slightest noise, and the melody of computation turns into cacophony. To keep the orchestra playing in harmony, you need a conductor who instantly spots wrong notes and corrects them without stopping the performance.

A choir where every singer hits the notes precisely sounds louder than you'd expect from a simple sum of voices. A hundred singers aren't just a hundred times louder than one: they're ten thousand times louder. In the world of atoms, something similar happens. In collective behavior discovered by Robert H.

Neurochips work differently from conventional computers, which are built according to the blueprints of von Neumann with separate memory and processor. At the core of these chips is a network of simple cells, similar to neurons, and, like water that evenly fills containers of any shape, they easily find a solution without unnecessary steps.

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.

Imagine a quantum phase transition as an intricate dance. Electrons whirl in strict order, each step representing their spatial arrangement, and the rhythm their dynamics. For decades, physicists could only see a blur of motion, unable to tell if the figures were changing or the music speeding up.

A quantum computer is like an orchestra where every musician must hit their note exactly. If one plays off-key, the melody falls apart. The musicians here are qubits, storing information.

Quantum tunneling — the ability of particles to pass through barriers forbidden by classical physics — powers stars with thermonuclear fusion, ignites primordial nucleosynthesis, and gives us flash memory.

Tuning a quantum processor is monotonous work: you need to calibrate each qubit — a quantum cell — much like a watchmaker adjusting dozens of tiny gears. Humans get tired and make mistakes.

Two pendulums hang from the same crossbar. A push, and they start swinging, gradually falling into and out of sync. In a topological qubit, Majorana particles, special excitations that can store quantum information, play the role of these pendulums.

Training a large neural network across hundreds of compute nodes is like making soup as a team: each 'chef' tastes the dish and tells the others what to adjust.

An invisible trap made of laser light held 11,000 atoms — a record for quantum engineering. Previously, physicists wrestled with a few dozen of these particles; now the count runs into the thousands. Each atom becomes a qubit — a quantum bit that is both zero and one at once, like a spinning coin balanced on its edge.

Imagine a library where instead of books, you have every conceivable combination of a few dozen quantum particles. The number of combinations grows like a snowball: add one particle, and the volume doubles. For fifty particles, there are more shelves than atoms in the visible universe.

A long chain of atoms, each a tiny magnet. They talk to each other and to a common field, like musicians in an orchestra who hear both the conductor and their neighbors. When the external field changes, the orchestra either plays out of sync or all instruments come in together: that's a quantum phase transition.

Light loves symmetry: in an open channel, it flows equally both ways. To steer it one way, physicists often use magnets. A new approach does without, using rotation — just the speed of a vinyl record — and interference from two atoms. Rotation changes the “pitch” of light for different directions, just as a siren’s tone shifts when a car approaches or recedes.

In 1948, engineer Claude Shannon laid the foundations of information theory. The Nyquist–Shannon theorem gave the first answer: to avoid losing a signal, you need at least twice as many measurements as the fastest feature in the signal. In 2006, the method of compressed sensing relaxed this requirement.

Quantum computers in the cloud are like a post office: you send a letter, and someone else reads the address and the contents. In ordinary computing, the server sees your data and algorithm. Blind quantum computing is an unopenable envelope: the server does the work but doesn't know what it's doing.

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.

A glass chip, threaded with 128 optical waveguides, has been turned into a kind of quantum pinball machine. The role of balls is played by photons — quanta of light, and instead of mechanical flippers, microheaters control the routes, instantly altering the optical paths.

Three people sit in three corners of a room. Each receives a sealed envelope from an invisible courier, but the couriers do not coordinate and have never met. The people open the envelopes and see a note with one word: "yes" or "no." They choose nothing themselves: they just read.

A radio picks up a broadcast through crackle and hiss. That's roughly how modern quantum computers work: the useful signal drowns in noise. The longer the computation runs, the more the interference distorts the result.

The rows of wires stretching from the warm room into the fridge holding the quantum chip look like a tangled telephone exchange from the last century. Each qubit needed its own analog channel for precise tuning, and the cables carried extra heat and got underfoot. Now researchers have placed a digital-to-analog converter right in the cold zone, next to the qubits.

Two musicians in separate rooms play the same note. The sound must be so identical that a listener can't tell who is playing. In the quantum world, these musicians are single-photon sources — particles of light that must be indistinguishable from one another.

Quantum particles can slip through obstacles like a ball that suddenly finds itself inside a hill and pops out the other side.

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 fisherman casts a net into a quiet backwater. The longer the rope, the weaker he feels the faintest nibble — the wave fades along the way. But what if the signal didn't die out but grew stronger? That's roughly the trick described by the authors of a study on an ensemble of particles placed in a field with a special 'stepped' force gradient.

A quantum computer is like an orchestra where every musician must play their part perfectly, or the melody falls apart. Previously, controlling qubits — the quantum 'musicians'—required a room full of equipment, and every extra wire added noise.

A quantum processor is like a busy intersection: the more cars, the harder it is for them to navigate without collisions. In the quantum world, qubits play the role of cars — elementary carriers of information that, unlike classical bits, can be both 0 and 1 simultaneously.

A quantum computer is like an orchestra where every musician must come in at exactly the right moment. Previously, to play a complex piece, you had to constantly move the instruments around — slow and noisy. The new scheme, called "parity architecture," keeps everyone in place, and the conductor simply changes the notes.

A judge walks into the courtroom but doesn't look at the evidence: he immediately delivers the verdict. That's how the new quantum sensor works: it doesn't measure the signal but directly decides which class it belongs to. In conventional quantum sensing, it's all like a detective story: first you gather clues (measure the signal), then you analyze them.

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.

Eighteen tiny cells line up in two rows on a piece of germanium. Each cell is a quantum dot — a trap for a single electron whose spin acts as a qubit. Previously, such systems could only be assembled in small numbers, but here we have an entire lattice working as a single ensemble.

Quantum computers promise to solve problems that are beyond the reach of ordinary computers. But their components, quantum bits, are very sensitive. One type of quantum bit is an oscillating circuit that can exist in two states, like a pendulum swinging left or right. These states store information.

A modern hospital sensor is like a sensitive microphone in a noisy hall. It picks up a weak signal from the heart or brain, but along with it comes the hum of machines, footsteps, the breathing of neighbors. Separating the desired sound from the interference is a science in itself.