nanometer

When an alpha particle tears through a gas, it leaves behind not a continuous track but a chain of individual ionizations: tiny flashes where electrons are knocked off atoms. In a living cell, such flashes damage DNA, and the denser they are packed into a clump, the more severe the damage.

Water in a glass looks continuous, but it's actually a dance of trillions of molecules constantly breaking and forming bonds. Seeing this dance in full detail was previously impossible: accurate calculations that account for the quantum properties of electrons could only handle tiny droplets of a few hundred atoms. The new model UBio-MolFM changes the game.

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.

The quantum many-body world is a jazz ensemble, where each electron improvises, continuously listening to all the others, and the overall wave function is born from this tense dialogue.

A stone falls into water, and ripples spread in all directions. Throw a handful of stones at once, and the ripples overlap: you can no longer tell which ripple came from which stone. A neutron beam hitting a detector looks much the same: a bright spot blurred by many causes.

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.

The cosmic microwave background is the afterglow of the Big Bang, which we see at millimeter wavelengths. But it also has a long-wavelength tail extending into the radio range.

A stone falls into a pond, and the ripples on the water tell for a long time where it sank. With a black hole, it would seem, things are different: everything that crosses the horizon (the boundary from beneath which not even light can escape) vanishes without a trace.

Conventional photolithography, used to make chips, hits a fundamental limit: light cannot draw features smaller than its wavelength. Here, they took a different route. First, they made sparse vertical ridges of oxide, then deposited layers of aluminum oxide, each one atom thick, onto them.

In a narrow gap between two plates, water from humid air collects on its own: this is capillary condensation. If the gap is only a few nanometers wide, water no longer behaves like a continuous liquid: every molecule counts.

A speck of glass floats in a laser beam. Air molecules, photons, even Earth's gravity give it little pushes, and by watching its jitter, you can tell what pushed it. But every measurement has a limit: the particle's own noise hides weak signals. Quantum mechanics sets that limit, but it can be bypassed.