Why does light act like it travels in particles?

Question

Why does light act like it travels in particles

Answer 1

Pure energy came together into tiny bundles that we call photons. Photons zoom in waves, in one direction until they bounce off something or get absorbed. We have taken pictures now of individual photons. When two or three photons come together, they can form tiny shimmerings that we call particles. Particles don't zoom. They stay put and basically quiver in quantum ways. We named those particles electron, neutron and proton. We also call particles, "matter". Particles can come together and form families called atoms. When photons are tangled up as matter, we call them "potential energy". When they get untangled, photons go zooming off as energy waves once again. Matter can change into energy and energy can change into matter. That is what Einstein's formula, E=MC2 means.

Answer 2

in 1800?, British scientist Young conducted his two-slit interference experiment. Such an example of interference can be seen wherever two waves overlap in space and time, whether the waves exist in light, water or virtually anything else. That experiment might have convinced most scientists that light travels as waves,

But in the early 1900s Albert Einstein confused the issue again. The photoelectric effect, where light landing on certain metal surfaces causes electrons to be released, makes sense only if light travels in discrete particles, which Einstein called "light quanta," and which are now called photons

Instead of continuing to argue whether light is waves or particles scientists concluded that light travels in waves in some circumstances and in particles in others, which led to the concept of wave-particle duality.

Niels Bohr posed the principle of complementarity, which states that something cannot act simultaneously like a particle and a wave. It may act like one or the other, but never like both at the same time.

Most scientist now accept that the characteristics of electrons, light and other things at the submicron level depended to some degree on whether anyone tried to observe or measure them. That idea came directly from quantum mechanics, which is essentially a set of principles that explains what submicron-size particles do

Answer 3

Light acts exactly like it "should". We are familiar with rocks, peas and the rain; observing & learning about them since we were born. So, we use the idea of a "particle" to describe light (some of the time) and the idea of a wave (much of the time) and a "ray" (from time to time). Its like describing a friend as acting like your sister (some of the time) and acting like your mother (some of the time) too. Your friend is not your sister or your mother but you describe her that way for your convienance, not because she's some DNA hybrid of your relatives.
You could turn it around and ask why a particle acts like light (some of the time) and not at other times...
As to "WHY" light behaves like it does. Thats a question with a million answers and with no answer. Science is pretty good at answering the "how" questions, but no so good with the "why"s.
I think the best answer is that it behaves in exactly the only way it can, the way it must - there's no choice for it. So to say it "acts" is to imply it has choices - like it is an actor rather than part of the scenery - and it is not. It is part of the landscape not part of the cast.

Answer 4

Blame it on the non-relativistic theory - quantum mechanics.

Light is made up of small, discrete packets of energy called photons (a photon is a quanta of light). They cannot exist in a smooth continuum - only in a stream of photons.

These packets are often referred to as particles, although they have zero mass and no electric charge.

As such, they behave as both a wave and as particles - a phenomenon demonstrated in many different kinds of experiments.

Note - this is theory, and the exact nature of light is an ongoing quest.

Answer 5

I think no on knows the answer for this "Why" ... Actually we treat the light as particles and waves to explain different theories... no one know the exact nature of light but because treating light as particle explains some of the theories therefore we treat it like that when required.

Answer 6

http://video.google.com/videoplay?docid=-4237751840526284618

Just stick to this explaination. It is a valid.

The new age stuff associated with the group that made this is speculative.