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In the 1980s, the DARPA speech recognition challenge settled the debate between statistical methods and hand-written rules, setting a common standard for the entire field.

In 1996, physicists asked: how much noise can a quantum channel withstand before it stops transmitting information? A phone call where every third word is replaced by random noise is still understandable. Up to what level of interference can the listener still grasp the meaning?

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.

A handful of coins drops onto a table — heads and tails land wherever they please. The same goes for an instantaneous snapshot of a quantum chain: in some places a particle is present, in others it is not. But behind the disorder lurks a precise angle. In this work, a chain of particles closed into a ring was considered. It was divided into four arcs: two were measured, two were left untouched.

Alice prepares a quantum particle in one of several states and sends it to Bob. The channel the particle travels through isn't perfect: it's noisy, scatters, interacts with the environment. Bob receives the signal and tries to figure out what Alice actually sent. This is the classic "prepare-send-measure" scheme, and there's always a risk of losing something along the way.

A quantum particle moves in a circle, passing through several stations. At each station, something happens to it — for example, its properties change slightly. After completing a full circle, the particle returns, but its state is no longer exactly what it was at the start.

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.

The quantum networks of the future resemble the Tower of Babel: each node speaks its own dialect. Some store information in the polarization of a photon — the direction of oscillation of the light wave. Others use time bins: that is, when exactly the pulse arrives.

Conventional antennas for precise direction finding must work coherently: they capture not just volume, but also the wave's phase at a given moment. The slightest tuning mismatch, and the direction is lost. The new method relies solely on signal strength. It's like finding your way in fog, seeing only the brightness of lights, not their color.

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.

Erasing even a single bit means releasing heat. This discovery by Rolf Landauer hinted that information is neither material nor illusory. Imagine that every event casts a shadow: that is information, the collection of all unrealized possibilities.

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.

A thermostat keeps a room at 20 degrees. Open a window in winter, and it kicks on the heat to restore equilibrium. The brain does something similar: it constantly predicts what will happen a moment ahead and corrects itself when wrong. That's how it learns.

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.

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 typical quantum bit is destroyed by the slightest disturbance — heat, magnetic fields. Physicists made a pair of atoms work together so that disorder wouldn't erase the record. Information was encoded not in each atom individually, but in the difference of their states — like the tension of a rope between two buoys.

In the quantum world, you cannot create a copy of an unknown particle's state – this was established by William Wootters and Wojciech Zurek in 1982, and Charles Bennett turned this prohibition into a data protection tool.

A quantum computer based on electron spins is like a row of tiny spinning tops. Each top spins either clockwise or counterclockwise: that's a qubit. To find out the result of a computation, you typically stop the top and see which way it fell. But if you have many tops, each one needs its own "eye"—an extra helper qubit.

Like an iceberg, the visible part of the code is the data, while beneath the surface lies a massive foundation of auxiliary particles. They quietly monitor noise and fix errors without touching the information. This approach squeezes many protected logical qubits into a modest number of physical ones. The experiment ran on a 98-ion processor inside an electric trap.

Quantum technologies often use light, but not just as a light bulb — rather as a carrier of information. One approach is to encode data in frequency: each 'color' of a photon can be a separate memory cell. The problem is that working with such color states requires a whole lab: a photon source, filters, modulators, detectors.

A quantum computer is like an orchestra where every musician plays their part, but the slightest thing throws them off. Errors in qubits happen constantly: an instrument goes out of tune, a musician misses a note. Usually, the conductor has to guess who made the mistake, and that's really hard.

According to one physical hypothesis, our voluminous world might be a projection from a flat surface. From such a Universe, tiny closed bubbles — baby universes — sometimes pinch off. For a long time, they were thought to be empty, devoid of internal diversity. It turned out that the information inside them is scattered, like shards of a broken mirror.

Picture an orchestra of 120 musicians playing in perfect unison — one false note and the harmony crumbles. That's the metaphor for a record-breaking quantum ensemble. Physicists have for the first time entangled 120 superconducting qubits, the building blocks of future computers.

A quantum computer is like an orchestra: each musician plays their part, but the slightest false note ruins the symphony. The physical qubits it is built from are noisy and error-prone. To protect computations, they are combined into logical qubits using quantum error correction.