elo
Is it possible for a light beam to travel for a long time without the beam circumference dilating?
As an example: I shine a laser in space and the beam has a diameter of 1mm, after the beam has traveled billions of kilometers, is it possible to still have the beam maintain its 1mm diameter or does it always increase its beam diameter?
It is theoretically possible, yet presents an incredible technical challenge.
This depends on the medium you're shining the beam through and the distance you wish it to travel. Over a long enough distance, any beam of light will fade due to it's photons being absorbed or refracted by other particles. The more dense the medium, the shorter the distance you can achieve.
EMPulse
18th October 2009 - 11:23 AM
The reason I asked this question has to do with gravitational lensing. I was thinking, if light always dilated then there would always be focal point of light after the shadow of an object obstructing light, over large distances. Producing the same affect as gravitational lensing, the “peak around” effect.