Tuesday, November 15, 2005
Sorry I Have To Do This
Mere Orthodoxy asked some science questions, it's just too fun not to answer one of them.
How light works is most simply described by Maxwell's equations but these came about before Einstein discovered photons (but he thought photons descrete and not quantum type particles) and describes electromagnetic radiation, of which visible light is just one small part of the spectrum, as purely a wave.
Let's try this -- some reaction occurs, it could be anything from a fire to electronic excitation of a metal (light bulb) to nuclear fusion (the sun) -- that reaction is exothermic (gives off energy) and expresses that exothermic nature by the emission of photons. Those photons travel through space and, in accordance with Heisenberg, act like either a particle or a wave depending on what experiment you use to figure out what it is. Light can be "received" electronically by things like CCD devices or photomultiplier tubes that turn the energy of the photon into an electronic signal that you record with a device, or they can be received by soemthing like your eye that converts that energy into a chemical reaction that transmits down your nerves to your brain for cognition.
Sometimes light does not come directly from the photon emissive reaction, but it bounces off of a surface which changes the energy of the photon in some way and thus you see colors, textures, and shapes.
Does that answer your questions? There are no short answers to questions like that. It is one of the most fascinating topics in all of science.
1. What is light? How does it work?Light is photons - little tiny massless quantum particles of electromagnetic radiation that, when asked, behave like waves but need no medium for transmission.
How light works is most simply described by Maxwell's equations but these came about before Einstein discovered photons (but he thought photons descrete and not quantum type particles) and describes electromagnetic radiation, of which visible light is just one small part of the spectrum, as purely a wave.
Let's try this -- some reaction occurs, it could be anything from a fire to electronic excitation of a metal (light bulb) to nuclear fusion (the sun) -- that reaction is exothermic (gives off energy) and expresses that exothermic nature by the emission of photons. Those photons travel through space and, in accordance with Heisenberg, act like either a particle or a wave depending on what experiment you use to figure out what it is. Light can be "received" electronically by things like CCD devices or photomultiplier tubes that turn the energy of the photon into an electronic signal that you record with a device, or they can be received by soemthing like your eye that converts that energy into a chemical reaction that transmits down your nerves to your brain for cognition.
Sometimes light does not come directly from the photon emissive reaction, but it bounces off of a surface which changes the energy of the photon in some way and thus you see colors, textures, and shapes.
Does that answer your questions? There are no short answers to questions like that. It is one of the most fascinating topics in all of science.
