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In a dark room, you can hold a glowing sphere without touching it: walls of light push it away but do not burn it. That is roughly how the trap built in Rio de Janeiro for yeast cells works. A conventional optical tweezer, that is, a focused laser beam, acts like tweezers made of light, but the light itself pierces the cell from side to side.

At night on a volcano summit, six telescopes stare at the same speck of light. Each catches its own copy of the wave, and if you combine their signals, you get an image that no single instrument could produce alone. But there's a catch: light captured by different stations cannot simply be added like photographs.

Gamma rays are the most energetic light in the Universe. But one part of them, the medium-energy range, long remained invisible: instruments couldn't catch them, leaving a gaping hole in the sky. Scientists call it the "MeV gap," named after the unit of energy these rays carry. The new camera works like a three-layer detective.

Catching light one particle at a time is like hearing a whisper in a roaring factory. An electron-multiplying camera (EMCCD) can do exactly that: it turns a single photon hitting a pixel into an avalanche of electrons that can be measured. These cameras are mounted on telescopes to spot a barely visible planet next to a dazzling star.

An empty resonator isn't truly empty. Even in an absolute vacuum, where not a single photon exists, quantum fluctuations persist. They resemble ripples on water in a dead calm: the surface appears smooth, but molecules keep jittering. Physicists have learned to turn this jitter into real waves.

A drummer stays silent, but from the pauses you can tell where he didn’t hit. Similarly, physicists built an image by catching not light, but moments of absolute darkness. The picture emerged from silence. In the experiment, they shone light from an ordinary lamp onto the object.

A security guard needs to check five rooms but can't go inside. He knocks on the door and listens: silence means someone is inside, while an echo means the room is empty.

When a massive star dies, a supernova explosion occurs, so powerful that a single flash outshines an entire galaxy. In this fire, billions of axions are born — invisible particles that leave almost no trace. Every second, trillions of these tiny things fly right through each of us, completely unnoticed.

An X-ray image usually brings to mind a bulky machine in a hospital. But such a picture can be taken by a device the size of a palm, assembled from hobbyist electronics. The authors took a Raspberry Pi mini-computer, a 12.3-megapixel camera, and a screen that glows under X-rays.

The universe is held together by an invisible scaffolding of dark matter. Part of it could be dark photons, ghostly copies of light that pass right through matter. The Dandelion experiment turned a spherical mirror into a super-sensitive ear: it gathers dark photons and translates them into the language of radio waves.

A flashlight in thick fog is useless: the beam scatters, and the reflected light drowns in noise. But if you tie two photons with an invisible thread, one can pass through the fog and come back, while the other stays safe. This connection is called quantum entanglement — when two particles behave as a single whole, even when far apart.

On a lab bench sits a laser trap — an invisible hand that holds a glass bead the size of a bacterium in midair. Next to it is a mirrored cavity where light bounces between two reflective walls. Scientists made the bead and the light exchange quantum entanglement: their states are now linked so that measuring one instantly reveals the other.

Quantum light is not just a stream of particles but an intricate pattern woven from space and time. A single photon can be stretched, squeezed, smeared across different directions.

Light, regardless of its source, consists of photons — elementary particles, quanta of the electromagnetic field. The simplest light detector, such as a photometric illuminance meter, operates in a binary mode: it merely registers whether photons hit it or not, giving a 'yes/no' answer.

A laser hits tissue, and the tissue responds with a barely audible click — a sound wave. Sensors pick it up, and from that, an image of what's inside is built. That's how photoacoustic imaging works: light reaches deep, and sound carries the picture out. In the new scheme, there are no sensors. Instead, several thin light beams are sent through the area where the wave has passed.

Light is a great tool for studying tissues, but it fades fast deep inside the body. Within a few millimeters, photons scatter so much that you can't make out anything. Scientists came up with a workaround: instead of shining light from outside, deliver a tiny light source right inside. The challenge is how to power that source without wires.

A camera that sees ultraviolet light typically costs as much as a nice car. That's because it requires a special crystal and a complex fabrication facility. Engineers in Korea took a different approach: they grabbed a run-of-the-mill chip, the kind made by the millions for phones, and sprayed a thin layer of metal-oxide nanoparticles onto it, like paint from a can.

Entangled photons are like twins: what affects one instantly affects the other, even if they are separated by kilometers. Until recently, observing such a connection required detectors that counted each photon individually in pitch darkness. Physicists simplified the task by swapping them out for a regular scientific camera.

A rubidium atom is like a lock that opens only with one key: a particle of light of a strictly defined color. Even under the fiery rain of the sun, where myriads of colorful 'keys' fall, the lock remains silent. But when the right one strikes, the atom gets excited for an instant, and the detector registers a click.

Light consists of portions — photons. Max Planck was the first to understand that light is emitted in quanta. Today, we can guide single photons. When such a photon encounters a fast shutter, it cannot be sliced — half a photon doesn't exist. Instead, a quantum mixture of states with different photon numbers emerges: zero, one, two, three..

When light passes through biological tissue or frosted glass, it scatters and loses the image. Researchers at the Paris Institute of Nanosciences have shown that a scattering medium can be tuned to transmit images encoded in the correlations of entangled photons while remaining opaque to classical light.

Sunlight collected by a Fresnel lens and passed through 20 meters of plastic fiber had a power of just 3 microwatts, a million times less than a typical laser pointer. That was enough to generate photon pairs correlated in position inside a nonlinear crystal. One photon from each pair passed through the object, the second was scanned by a detector, and coincidences built up the image.

Light is a finicky guest. It flies into a cavity but doesn't stay: part of the pulse inevitably reflects and carries away quantum information. Classical single-pass capture schemes hit this limit no matter how much you improve control. Reflection was considered a loss, but the authors of a new study suggest looking at it differently.

Two images of the same place: one taken in the morning from a drone, the other in the evening from a satellite. The first shows shadows from trees, the second shows glints on the water. It's like two accounts of the same event in different dialects: the words are similar, but the grammar is different.

In a dark room, a laser beam draws a bright spot on the wall. Light seems warm and uncontrollable, but for three decades physicists have used it as a conductor's baton, making atoms dance in unison.