What is the behaviour that supports the dual nature of electromagnetic radiation?

Electromagnetic radiation (i.e. infra red and so on) have a wave-particle duality meaning it can behave as a wave or as a photon (that exhibits particle-like behaviour), I want to know the behaviour that they exhibit that supports this theory...can anyone help?What is the behaviour that supports the dual nature of electromagnetic radiation?
Young's slit experiment:



http://www.youtube.com/watch?v=pSHlp9z3n…

http://www.youtube.com/watch?v=RlPvzn5sG…



Photoelectric effect, slightly more complex.



The principle behind the Photoelectric effect basically is that if light is a wave then the only factor which should affect the amount of electrons escaping the electrostatic attraction of the metal should be the amplitude (i.e. the amount of energy in the wave) but not the frequency of the wave- doesn’t matter how many times you hit a lorry with a hammer, its never going to move. Also, if the light waves amplitude is too low, then you get no electrons escaping from the electrostatic force, because the waves won’t transfer enough energy to liberate them themselves. But…



Planck’s constant, which is referred to as h, and apparently h=6.626x10^(-34)Joules,

showed that energy could only come in discrete energy ‘packets’, which lead Einstein to believe that light also came in discrete energy packets, which would mean that light itself would be a particle- a photon. The amount of energy transferred would be Planck’s constant times the frequency of the photon (because frequency is proportional to the energy level) which would mean that frequency of the electromagnetic radiation would affect the kinetic energy of electrons escaping from the electrostatic force, because the photons with higher frequencies would have more energy, and so transfer more. This would mean that leaving the intensity (the amount of photons hitting the surface per unit of time) the same, but increasing the frequency of the light, would raise the maximum kinetic energy level of the electrons which are liberated, and that leaving the frequency constant, and increasing the intensity of the light would mean more electrons would be released, but their kinetic energy would remain constant. This would also mean that electromagnetic radiation with too low a frequency would not liberate any electrons, but that if you have a really high frequency, even if you have very low intensity, then you will still liberate some electrons.



Robert Andrews Millikan conducted experiments in 1910s which has since verified all of the predictions set out by the photoelectric effect.



However, light can not be just a particle, as certain aspects of it have been proved to be wave, or wave-like, namely in the “double-slit experiment”, but many others as well.



This is the site I used. Its got to be the best for clarity,

http://www.colorado.edu/physics/2000/qua…



good luck :DWhat is the behaviour that supports the dual nature of electromagnetic radiation?
in explaining the phenomena like interference ,diffraction ,polarisation light is treated as a wave where as it is treated as a photon to explain photoelectric effect , compton effect.What is the behaviour that supports the dual nature of electromagnetic radiation?
Hope this helps.

A time-domain method with isotropic dispersion and increased stability on an overlapped lattice

Forgy, E.A. Weng Cho Chew

Dept. of Electr. %26amp; Comput. Eng., Illinois Univ., Urbana, IL;



This paper appears in: Antennas and Propagation, IEEE Transactions on

Publication Date: Jul 2002

Volume: 50, Issue: 7

On page(s): 983- 996

ISSN: 0018-926X

INSPEC Accession Number: 7370039

Digital Object Identifier: 10.1109/TAP.2002.801373

Posted online: 2002-11-07 17:09:07.0

Abstract

A time-domain method on an overlapped lattice is presented for the accurate and efficient simulation of electromagnetic wave propagation through inhomogeneous media. The method comprises a superposition of complementary approximations to electromagnetic theory on a lattice. The discrete space-time (DST) method, is set on a pair of dual lattices whose field components are collocated on their respective lattice sites. The other, the time-domain element (TDE) method, is set on overlapping dual lattices whose field components are noncollocated. The TDE method is shown to be a generalization and reinterpretation of the Yee algorithm. The benefits of the combined algorithm over comparable methods include: (1) increased accuracy over larger bandwidths; (2) increased stability allowing larger time steps; (3) local stencil-satisfying boundary conditions on interfaces; (4) self-contained mathematical framework; (5) it is physically intuitive.



Enjoy