Gerard K. O'Neill proposed using a single accelerator to inject particles into a pair of tangent storage rings.

This might conceivably be done, for instance, by injecting high-energy particles into a viewpoint, causing the wormhole to implode.

"Injecting sunlight-scattering particles into the stratosphere appears to be a promising approach," Dr. Teller wrote in The Wall Street Journal.

CMEs can inject charged particles into the Earth's magnetic field which, if accelerated, lead to the beautiful aurora.

"What a product like Snomax does is inject particles into the water, and these particles seed the drops so that ice crystals form around the particles," Mr. Moore said.

One, called uterine artery embolization, involves injecting particles into the arteries supplying blood to the fibroids to block them.

Eruptions on the Sun inject high-speed particles into the solar wind, and these can cause geomagnetic disturbances on reaching the Earth.

For example, he mentions the Argus experiment, in which atomic bombs were exploded above the South Atlantic to inject particles into the Earth's radiation belts.

Under imaging guidance, the interventional radiologist will enter selectively into both uterine arteries and inject small (500 m) particles that will block the blood supply to the fibroids.

Tail reconnection allows release of energy stored in the Earth's magnetic tail, injecting particles deep into the magnetosphere, causing auroral substorms.