Playing with the speed of light

2000/04/01 Elhuyar Zientzia Iturria: Elhuyar aldizkaria

• Fisika

Nothing travels faster than light. In the vacuum is so, and in other ways? The speed of light in the vacuum, that is, in an immaterial environment, is 300,000 km per second. On the water, however, its speed is 225,000 km per second and its diamond is 125,000 km per second. The more compact the medium is, the slower the movement of light. A group of Danish physicists managed to observe the light that moved a year ago at 61 km/h.

Using Bose-Einstein's condensation theory, light went through an environment very close to absolute zero (-273,16ºC). At such low temperatures the atoms are practically motionless and very special properties develop, since light very slowly passes through this medium. The Danes have just broken the record a year ago, as they have managed to make the speed of light 1.5 kilometers per hour, 600 million times lower than that in the vacuum and 3.3 times lower than that of man walking. According to the researchers, the phenomenon described may have important applications in the field of telecommunications in the future.