How does light work?

Answer 1

Your question is extremely ambiguous! Do you mean 'how does a light work'? Do you mean 'how can light produce work'? Are you simply enquiring as to the nature of light?

I'll assume the latter is true.

Light is electro-magnetic radiation. All electrically-charged bodies emit an electric and a magnetic field. These two force fields are intimately connected through Maxwell's equations (credited to Maxwell but written in their accepted form by Heaviside).

Because these two 'mysterious' forces could not exist independantly of each-other they were assumed to be different parts of the same force. The electro-magnetic force was born.

Electromagnetic force is carried by the photon boson. Over history there were two schools of thought about photons. Some scientists believed in the corpuscular theory of light (that light is made of corpuscles - or particles). Some believed in the wave nature of light. There was evidence for both. Young's double-slit experients suggested that light behaved like a wave. Experiments by Neils showed that light behaved like a discrete particle. In the early part of the last century, quantum theory produced the first attempt at uniting the two schools of thought by suggesting that ALL matter and energy can exist as either a wave or a particle, or both. Wave-particle duality was born.

Importantly, whether photons are waves or particles depends on the experiments you are performing and the results you expect to see. Both are nothing more than mathematical concepts designed to try to simplify nature.

In recent years it has become clearer that light is in fact the entity that defines the very dimentions of the universe. Einstein realised this when he formulated his special theory of relativity. He said that the speed of light was constant, and that the dimentions of space and time were totally dynamic. In fact, relativity went on to describe gravity and predictions based on this theory have led to the discovery of countless new planets, stars and galaxies!

I personally find that light is the most facinating subject in all of Physics. I can not do justice here how complex it is nor how rewarding an understanding in the nature of light can be. I am, in fact, doing a PhD in Photonics and could go into any amount of details about optical vortices, solitary waves, beams, photonic crystals, nano-particles or metamaterials or infact any photonics subject you care to mention and ALL OF THESE RELY ON THE COMPLEXITY OF LIGHT.

So, as you can see, the question of 'how does light work' can only be answered with the following line:

'very well, thanks'

Answer 2

The luminiferous ether...

I'm kidding. Light doesn't need a medium to travel through. This is because it is an electromagnetic wave/particle that is massless, unlike sound waves that are compressional waves of air. It acts like a wave and can be solved using wave solutions, but it also acts like a point.

Short answer: oscillating electric and magnetic field that are perpendicular to each other.

Long answer: light is categorized by the wavelength and the frequency. The higher the frequency the higher the energy and the shorter the wavelength. The lower the frequency the higher the wavelength and the lower the energy.

This is because lamda*nu = the speed of light where nu is inverse frequency.

Answer 3

Rather well, actually ☺

Light is a stream of 'photons' which are massless particles which, sometimes, act like waves inststead of particles.

Look at the articles a few other folks have referenced, or type 'light' into a search engine ☺


Doug

Answer 4

Photons travel at the speed of light at different wavelengths.

This light bounces off items and is reflected into peoples' eys. Human eyes have a protein that changes structure (rhodopsin) when light hits the back of your eye. This causes an electrochemical signal to travel to your brain so you can interpret whats going on.

Answer 5

Light is comprised of massless quantum particles/waves called photons, which are produced upon the release of a signifcant enough amount of energy.
Sunlight is produced through nuclear fusion, when hydrogen atoms fuse together by way of the suns high gravitational field to form helium...photons are released.
With a light bulb, an electrical charge is sent through a wire filament, the energy of which causes the filament to release photons and glow.

Answer 6

There are accepted models of light and many theories, but at the most fundamental level, no one knows.

Answer 7

You flick the switch and 'Voila' you have light! Amazing!

Answer 8

http://en.wikipedia.org/wiki/Light