Photon is the light particle. The way light travels (as sound, for example, does) is called a wave (motion). You may have heard of the sinal wave and that it represents the travel (motion) of sound? Sinal wave, mathematically, is the curve which results when you plot trigonometric function (y) = sin (x) in an orthogonal coordinate system. The variances in wave motion are, then, represented by different amplitude, frequency and wavelength. Our eyes perceive colours based on the wavelength light reflects and refracts from the object we're observing, for example. Our eyes contain receptor cells for basic colours and our brain interprets the observed wavelength(s) of light which enables us to see colours. PS: you may also have heard that "light travels straight". This is, practically, true, however the motion of light is still represented as a wave. But of one, of course, whose amplitude approaches zero.
I like your physics background, how you explain stuff and stuff.. School is important, (or that you listen to stuff in physics class). I for one am grateful.
Then you'll love this. http://www.youtube.com/watch?feature=player_embedded&v=vwzbU0bGOdc In case you haven't heard of Lawrence Krauss, he is one of the worlds most famous Astrophysicists. His "Universe from Nothing" angle is purely theoretical, but everything else is fact.
some weird **** going on here...I can embed video just fine, but then it disappears when I hit submit....
No. I was just elaborating on the nature of light, that it's both a particle and a wave, afaik. As has been stated (and I concur), photons are massless particles, which is an interesting property as such. Particles are not energy in themselves, but can and do have energy. Any moving particle with mass has kinetic energy (E= (1/2)mv^2), for example. Which actually gives another interesting result about photons: even if they move extremely fast, they don't have kinetic energy as their mass is zero. In purely mechanical terms.
Well, as it happens I've had to study physics and especially mechanics quite a bit due to my profession (engineer) I don't consider myself to be an expert in physics, far from it, but think I have a pretty decent understanding of the basics of mechanics, electricity and thermodynamics.
^ Imho no. I don't think photons can even "collide" in that way. When a ray of light hits a wall, it's motion stops but it exerts zero energy or force on the surface. In this sense it's also true what IcE said, that a photon or light isn't a particle. It behaves differently from other particles (with mass). However particle physics is an area of it's own and I can't say I'm too familiar with it.
^ inertia affects only objects (particles) with mass when they move in a gravitational field. However, did a bit of checking and photons do have energy, based on their frequency or, inversely, wavelength. This is derived from the theory of relativity. So even if photons do not have mechanical energy, as they're massless, they carry an energy of their "own", in laymans terms.
Damn you're an engineer AsiJu, how do you like it? I also thought of going down on that line. Still thinking though, is it paying off, what kind of stuff do you do everyday?
Don't they give away their energy by provoking a new photon, the one we see when our first photon comes from the sun and hits the wall? We should actually discuss such things in another thread, worthy a place of it's own. Yet it's basic school knowledge still.
Of course they have energy otherwise they wouldn't exist. Pill, Not yet man, at work, will do later. Thanks for the link bro. What do you mean? You mean mere reflection?
Cool. I can give u one for a presentation at Harvard by the engineer heading NASA's Warp Drive/Ion propulsion project if you're interested. They even have a concept model spacecraft, done by the same guy who designed USS Enterprise no less.. And I don't mean the aircraft carrier.... Sounds like fiction, but it isn't.... http://www.nasa.gov/centers/glenn/technology/warp/warp.html http://www.nasa.gov/centers/glenn/technology/warp/warpstat_prt.htm
If a photon has energy, it has mass, how small it is anyway. So what happens when a photon hits the wall? Reflection is one thing, but with unlimited photons, could one get through the wall? If so they'd have mass. And the photon coming back fro mthe wall, the one I see with my eye, is it the one coming from the sun and being reflected, or is it another photon created by interaction with the wall? I really should get those books out from the box in my basement...
Damn that's awesome, can't wait to see till something real gets out, yeah I'll check that out dude. I've seen some warp drive videos on utube.
