Our page on Facebook with over 2 million followers was deleted. Follow the new page here: Physics-Astronomy.com Facebook Page

default | grid-3 | grid-2

Post per Page

Speed of light not so constant after all- New experiment proves

Light doesn’t, at all times, travel at the speed of light. A fresh experiment exposes that converging or controlling the configuration of light pulses decreases their speed, even in vacuum circumstances. A paper reporting this new study was announced online at arXiv.org and also acknowledged for publication. The paper defines tough experimental proof that the speed of light, one of the most significant factors in physics, should be taken as a limit instead of unchanging rate for light travelling through a vacuum. Scientists directed by optical physicist Miles Padgett at the University of Glasgow proved the effect by competing photons that were alike apart from their structure. The structured light steadily reached a bit late. However the effect is not detectable in ordinary life and in most industrial applications, the new study highlights essential and previously unappreciated refinement in the behavior of light.

The speed of light in a vacuum, generally represented by c is an essential constant in physics, predominantly in Einstein’s theory of relativity. Even though calculating c was once considered a significant experimental problem, it is now basically stated to be 299,792,458 meters per second, as the meter itself is precisely defined in terms of light’s vacuum speed. Usually if light is not roaming at c it is because it is travelling through some kind of material. For instance, light slows down when travelling through glass or water. Padgett and his group speculated if there were essential factors that might change the speed of light even in a vacuum. Physics textbooks view light as plane waves, in which the heads of each wave travel in parallel, a lot like ocean waves approaching a straight shore. But even though light can generally be estimated as plane waves, its structure is in fact more complex. For example, light can unite upon a point after travelling through a lens. Lasers can form light into focused or even bull’s-eye–shaped rays.

The scientists created pairs of photons and directed them on unalike paths toward a detector. One photon passed straight through a fiber. The other photon passed through a couple of devices that influenced the structure of the light and then converted it back. According to previous study the structure should not make a difference and the two photons would have reached at the same time. But that didn’t take place. Measurements shown that the structured light steadily reached more than a few micrometers late per meter of distance traveled.

Greg Gbur, an optical physicist at the University of North Carolina at Charlotte, clarifies that the outcomes won’t modify the way physicists gaze at the aura originating from a lamp or flashlight. But he says the speed modifications might be significant for physicists studying exceptionally short light pulses.

1 comment

Unknown said...

what is the mathmatical relation b/w structure of photon & its velocity & medium.velocity of red light is greater than violet

Error Page Image

Error Page Image

Oooops.... Could not find it!!!

The page you were looking for, could not be found. You may have typed the address incorrectly or you may have used an outdated link.

Go to Homepage