Browse Physics

Internal stress in a glass material is an important source of strength. Theory and experiments provide a new molecular-scale understanding of the process by which such stress develops.

An equation that describes a wide array of phenomena can be directly tested by watching the equivalent of a drying coffee drip.

A projectile striking granular material generates a series of acoustic pulses that propagate down from the impact site.

Charged beads floating in a plasma spontaneously form a two-dimensional liquid consisting of small, ordered regions that slide past one another and may mimic the motions in real liquids.

Two-dimensional simulations provide the first element-by-element accounting of the fluid and grain flow in an underwater avalanche.

The atomic force microscope, introduced in 1986, provided atomic-scale pictures of surfaces, with few limitations on the type of sample.

A process for making wavy tubes in a controlled way could lead to the predictable fabrication of complex shapes.

A proposed device improves on past designs and would sort small particles from large ones to a purity of over 99 percent, without any moving parts.

A new technique measures each unit of charge that accumulates on a submerged plastic bead, unprecedented resolution for a liquid-solid interface and an experiment that may benefit a variety of commercial devices and processes.

An improved version of a technique for folding tiny objects from a thin membrane uses a magnetic field to affect the shape. The membrane wraps around a droplet of fluid that distorts in response to the field.

The structures within a pile of soil or grain that allows it to bear weight depend only on the average number of neighbors for each particle, not on any details of the types of particles or even on the presence of gravity.

Experiments with soap films clinging to an adjustable wire framework show that the shape of the film depends on its history.

The complex topography of a crumpled piece of paper has only two basic types of regions, and they can be combined to build up the whole surface, according to calculations.

Simulated soils made of glass beads and various pastes dry at different rates, depending on the properties of their smallest particles. The work suggests new ways to study an aspect of soil that is critical for agriculture.

Drops of water striking a bed of grains can leave a wide range of crater shapes and sometimes a bigger impression at low and high impact speeds than at medium speeds. The work may help geoscientists identify ancient formations.

Experiments on microscopic beads suggest that crystals melt suddenly, with no liquid-solid coexistence phase, when the crystal is only a few layers thick–somewhere between 2D and 3D.

Using a new laser technique, researchers can make a wide variety of bubble shapes–such as squares and donuts–some of which may prove useful in manipulating nanoscale objects.

The textbook rule that friction increases the more you press an object onto a surface doesn’t always hold for liquid drops.

Detailed images of surface waves on the membrane of a living cell support a theory that the protein machinery involved in the cell’s locomotion are responsible for the waves.

Chains of spheres representing polymers can arrange themselves into a crystal, which turns out to be the highest entropy structure, according to computer simulations.