Quantum Ghosts in the Hall of Mirrors
In quantum mechanics, some states defy intuition: their probability distributions dip into the negative, like mirages leaving only indirect clues.
Quantum Record: 120 Entangled Qubits
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.
Quantum Simulator Discovers Plasma Memory
Physicists used a quantum simulator — a device that mimics the behavior of charged particles, to study their collisions at enormous energies.
False vacuum in a ring of atoms
Emptiness isn't always empty: it can hide energy, like supercooled water hides ice. Physicists call this false vacuum — a state that only needs a nudge to cascade into the true one.
How the Quantum Vacuum Blurs Time
Time is like a highway: from afar it looks flawlessly paved, but zoom in and every pothole appears. These bumps are the quantum fluctuations of the vacuum, making it impossible to measure the journey exactly. Physicists built a clock model whose operation relies on spontaneous particle creation from the void.
Quantum Leapfrog: How Vortices Play in Liquid Light
In superfluid helium, a state where liquid flows without friction, quantized vortices spontaneously arise: microscopic funnels resembling whirlpools in ordinary Water, but governed by quantum mechanics.
Classical Light Masters 'Quantum' Tricks: Negative Probabilities Without Quantum Magic
The Wigner function is a kind of topographic map of probabilities: hills correspond to regions where a particle is most likely to be found, and valleys to where its appearance is practically ruled out.
Heat from the void: how to catch the Unruh effect
The void is deceptive. William Unruh showed that an accelerating observer perceives the vacuum as hot. The effect resembles the particle birth near black holes, predicted by Stephen Hawking, but instead of spacetime curvature, acceleration is at work.
Levitation on Quantum Glue: The Casimir Effect in Action
The space between two closely spaced surfaces is far from empty: it's a seething "quantum glue." Within it, quantum fluctuations continuously pop in and out of existence: microscopic bursts of energy in electromagnetic fields that, according to quantum theory, give the vacuum a dynamic structure.
Gravitational Waves from the Boiling Universe: A New Precise Method
In the infant universe, right after the Big Bang, space was expanding rapidly, and the vacuum resembled a superheated liquid. When 'boiling' began, bubbles of true vacuum emerged. Expanding at the speed of light, they triggered gravitational waves — tremors of space itself that have reached us.
How an Electron Crystal Generates Unprecedented Beams
A material just one atom thick and of record purity — only one foreign atom per million — becomes the setting for a remarkable phenomenon. When cooled to near absolute zero, the electrons inside, like musicians in an orchestra, freeze into a strict order, forming a crystal. This state, predicted by Eugene Wigner nearly a century ago, has now been observed in detail.
Magnetic field turns the void into a motor
Two metal plates in a perfect vacuum attract each other. Even Richard Feynman compared emptiness to a boiling foam: particle pairs are born and immediately vanish, creating the Casimir effect. If the plates are asymmetric, they also start to twist — that's a vacuum motor.
But rotation doesn't require oddly shaped parts.
Quantum Ripples That Gave Rise to Baryonic and Dark Matter
In the first instants after the big bang, the universe was a quantum vacuum where pairs of particles and antiparticles, virtual "guests" from physical nothingness, spontaneously appeared and almost immediately annihilated.
Quantum Noise Saves Electronic Patterns
In a dark room, an invisible lamp flashes. Its light is unlike anything familiar: it has no steady brightness, only rare but powerful bursts. This is bright squeezed vacuum — a state of light with no ordinary wave but strong quantum fluctuations. It is with such light that physicists bombarded xenon atoms.
Birth of Light from the Quantum Void
The quantum vacuum is not emptiness, but a tautly stretched string, where particles constantly appear and vanish. Abruptly changing conditions, like shifting the mirrors of a microcavity, causes the 'string' to emit real photons.
The Rubber Band That Gives Birth to Antimatter
The void can produce particles if a strong enough field is applied. Physicists call this the Dirac–Klein paradox. Previously, explaining it required the most complex calculations of quantum field theory. But we can make do with a visual image: a tightly stretched rubber band with a knot. The knot is a particle.
How the Void Sticks Atoms to the Wall
Vacuum is not silent emptiness, but a boiling cauldron of quantum fluctuations, born from nothing and vanishing in billionths of a second. This invisible symphony acts like a constant wind, pressing an atom against a wall — as if a powerful bass note pushes a light ball.
Vortices in the Ocean of Vacuum: How Spin Dictates the Birth of Matter
According to the Standard Model, the vacuum is not emptiness but an ocean of virtual ghost particles. An ultra-strong electromagnetic field, like a storm, yanks electron-positron pairs into reality.
Magnetic Field Makes Emptiness Bloom
An invisible film, a quantum field, is stretched over a rubber bagel. While the bagel is small, the film stays taut and doesn't sag anywhere: the vacuum remains empty. But once you stretch the bagel to a certain size, a dent spontaneously appears in the film — the field starts to be felt at every point.
This dent is not random.
Birth of Particles in an Expanding Universe on a Quantum Computer
The early universe resembled a rapidly inflating balloon: it expanded so fast that light couldn't keep up with its own edges. Then this frantic acceleration gave way to calm expansion. The balloon was no longer being blown up, and it began to slowly deflate. At the moment of the regime change, emptiness didn't stay empty: from it, as if from an overheated boiler, pairs of particles burst forth.
Echo of the Void: How to Catch the Invisible
A palm hovering over a hot stove feels the heat even when the surrounding air seems cool. Something similar happens to electrons in the Aharonov–Bohm effect: the particle senses an electric voltage even though it enters a region where the field has already been switched off.
Alchemy of the Void: Nonlocal Magic of Particle Birth
When an electric field reaches monstrous strength, emptiness ceases to be empty. Back in the mid-20th century, Julian Schwinger showed that the vacuum literally explodes with pairs of particle-antiparticle if the field is intense enough.
The Singularity That Never Was: How Quantum Tango Erases the Beginning of the Universe
In physics, there's an old ache. General relativity paints the beginning of the universe as a point — a singularity where equations break down and volume shrinks to zero. Quantum mechanics hints that at the most critical moment, something goes differently than classical physics predicts.
The Vibrating Edge of the Universe: A Surprising Phase Shift
Stephen Hawking imagined that the universe was born not from an explosion, but by smoothly emerging from a quantum 'nothing.' In worlds with concave geometry (anti-de Sitter space), such a birth acquires a rim, like the hoop of a drum.
How the Universe is Born from Nothing
Quantum nothingness resembles water in a pot just before boiling. From time to time, a bubble spontaneously swells up — but not of steam, but of an entire universe. Such a bubble doesn't collapse; instead, it inflates into spacetime, triggering its own Big Bang. The only question is how often this happens.
Vacuum Turns an Ordinary Superconductor into an Extraordinary One
A superconductor carries current without resistance, like water running through a pipe without friction. The secret lies in electron pairs: two electrons stick together as one, even though they normally repel. In an ordinary superconductor, the spins of the electrons in a pair point in opposite directions: this is the singlet state.
Electron and muon magnetic moments search for New Physics
Electrons and muons are tiny magnets. Their magnetism is slightly more than two (in special units), and this 'excess fraction' (anomalous magnetic moment) arises from constant ripples in the vacuum: particle pairs momentarily pop into existence and vanish.
The Universe as a Quantum Fog
The early universe expanded at an unimaginable rate — faster than light could cross it. In this boiling cauldron, any region of space resembled an open can of paint: its boundaries continuously captured new 'vapor' from outside, while some of its own contents irrevocably escaped.
How a Pair of Black Holes Creates Particles from the Void
Two black holes circle in a slow dance, gradually drawing closer. Their motion perturbs spacetime itself, like two heavy balls rolling on a stretched sheet, making it tremble. These tremors are what we call gravitational waves.
How to Hear the Warmth of the Void
The vacuum is not as empty as it seems. If an observer moves with acceleration, the vacuum around them heats up: this was predicted by William Unruh back in the 1970s. The effect is akin to black hole radiation, but in flat space.
Speedy quantum bubbles mimic the early universe
After the Big Bang, the universe may have been stuck in a false vacuum — a temporary state like a soap bubble ready to pop. A rare true vacuum bubble could then erupt, stretching space in the blink of an eye.
Vortices in the Quantum World
A regular object moves along a predictable path, like a ball. In the quantum world, a particle is smeared into a probability cloud. To find order in this fog, scientists have recast Schrödinger's equation in the language of flowing water.
Quantum Boiling of the False Vacuum
The quantum vacuum is not a dead void but a boiling cauldron of probabilities. In some theories, our Universe is frozen in a metastable state: like superheated water, it's ready to explode into steam at the slightest nudge.
A Quantum Twist at the Heart of a Black Hole
A black hole is where the usual rules break down. At its center, according to classical physics, lurks a singularity: a point of infinite density where everything that falls in gets crushed. Quantum theory was supposed to soften this picture.
Vacuum Around a Thin Shell
Quantum vacuum is not absolute emptiness. It is more like a taut membrane that constantly ripples from invisible particles popping in and out of existence. Even in total darkness, this membrane trembles. Physicists decided to see how it behaves around a thin spherical shell, inside which is ordinary flat space, like in our room.
How to Catch the Thermal Glow of Emptiness
If you accelerate an observer to near-light speed, the emptiness around them stops being cold. A thermal glow emerges — an effect predicted in 1976 and named after William Unruh. For earthly accelerations, this glow is vanishingly faint, like a whisper at a rock concert.
Heat from the Void: How to Catch the Glow of Acceleration
In a room, air touches the skin, and we feel its temperature. But if your body suddenly accelerated at a colossal rate, heat would come even from absolute emptiness. This is not fiction but a strict consequence of quantum field theory: for an accelerating observer, the vacuum becomes a warm bath.
How to Catch the Heat of Emptiness with a Superconducting Circuit
Empty space is not as empty as it seems. According to quantum theory, the vacuum is filled with particles that constantly pop in and out of existence. In 1976, physicist Bill Unruh showed that if an observer moves with acceleration, this 'quantum soup' turns into a genuinely warm bath for them — the Unruh effect.
Frozen Complexity of a Black Hole
Hot tea cools down, a pendulum comes to rest — nature loves equilibrium. But a charged black hole can reach a special, extreme state: the mass becomes minimal, and the temperature drops to zero.
Gravity Overflows Its Banks
A cloud of waves collapses under its own gravity. While it's loose, everything goes by the book: the field oscillates gently in nearly flat space, and approximate formulas work perfectly. But add just a bit more energy, and the picture changes.
Physicists used a numerical model to catch the moment when simple calculations stop describing reality.