One example, where almost all specifics are omitted in favor of promises -- that might or might not be kept.
In the early months of 1999, the speed of light was diminished to 17 meters per second. In this paper, this experiment will be discussed. Also a short, qualitative explanation of the physics mechanism behind this phenomena will be offered.
The velocity of light in vacuum is slowed in a media by a factor called the index of refraction. Using two nearly degenerate levels in a sodium-atom gas, Lene Hau produced a index of refraction of nearly 18 million and slowed light to 17 meters per second.
This abstract is more introduction than abstract.
Einstein theorized that nothing can travel faster than # 108 m/sec, the speed of light in a vacuum. However, light, when not in a vacuum, does not go at this speed. It travels at speed less than this, and how much less is determined by the physical characteristics of the medium. What happens when a particle is accelerated to a speed greater than light in the medium? In this case, the radiation given off is called Cerenkov radiation, and this discovery has proven to be quite useful in the field of particle physics. The following discusses a bit of the physics of Cerenkov radiation, as well as some insights into how Cerenkov radiation can tell us things about microscopic particles, that would perhaps be unknowable otherwise.
Light travels more slowly in media than in vacuum. High-energy particles traveling near the vacuum velocity of light slow down when they enter a media, in part, by emitting Cerenkov radiation in a narrow core centered on the particle's direction of motion. Detection of the blue-shifted radiation can be used to measure the direction and speed of high-energy particles.
This has more detail; is is useful detail?
Parallax is an optical phenomena caused by the apparent shift of a stationary object with respect to its background when an observer views it from different locations. With trigonometry, this phenomenon can be used to measure distance to an object between the observer and a stationary background.
The distance to a star can be estimated from the difference in the apparent position of a star by two separated observers -- such as at two sides of earth. This earth-to-star measurement limited to 300 light years by the largest separation of observers -- width of earth's orbit around the sun -- and errors in measuring the apparent positions