NSX Posted March 20, 2003 Share Posted March 20, 2003 Well, like the thread name says: What causes us to see colours? Not the biological reason of how it goes into our eyes, and our brains re-intrepret the data. I mean, I know white light is a form of wave, which when diffracted, can seperate into other forms of electromagnetic radiation, with different wavelengths; red having longer wavelengths than say, blue. But what causes these wavelengths? I'm doing a Chemistry lab right now; and want to go a little beyond; Anyways, I'm frazzled for now; thanks for any replies. Link to comment Share on other sites More sharing options...
fafalone Posted March 20, 2003 Share Posted March 20, 2003 A little beyond? It's way beyond. It has to do with the interactions between photons and electrons in the atoms... especially unpaired electrons. Link to comment Share on other sites More sharing options...
Radical Edward Posted March 20, 2003 Share Posted March 20, 2003 "white" is just your brains interpretation, what is actually happening, is that your eye is recieving signals from lots of different coloured photons, adding them all up and getting white. I could go into the details of 11-cis/trans-retinol but I won't as for what causes those colours, essentially it is the energy levels of the atoms/molecules, which may or may not interact with a particular frequency of light. Spontaneous emission (as in light) occurs when an electron decays from an excited state (from a high energl level to a free spot in a lower energy level), and the height of the fall dictates what the wavelength of the light is. A common one is that orange you see in sodium lamps, which is a specific atomic transition (actually for completeness it is two specific wavelengths which form part of a doublet, but that is extra detail). Reflection and absorption are similar effects, and the issue is complicated further when you look at molecular interactions with light as there are extra effects which broaden the emission characteristics, extra excitations that may occur and so on.... Link to comment Share on other sites More sharing options...
fafalone Posted March 20, 2003 Share Posted March 20, 2003 Originally posted by Radical Edward I could go into the details of 11-cis/trans-retinol but I won't Why not? I for one would like to hear about the details. Link to comment Share on other sites More sharing options...
Radical Edward Posted March 20, 2003 Share Posted March 20, 2003 well I thought it was a bit much for him really essentially all light reception is based around one molecule, 11-cis-retinol (11CR), that is bound up in a protein shell. It is the protien that surrounds it that is responsible for the difference in colour reception, rather than the actual 11CR itself. when light is absorbed by the 11CR (the probability of absorption being determined by the protein) it changes form to 11-Trans-Retinol (an excited version of 11CR), which has a slightly different physical shape. This then effects the ion transport within the rod or cone, and should enough be excited, you get a nerve impulse. This is slightly rusty, as I don't have my notes with me to explain the more precise details, of absorption mechanisms, or which ions are affected etc. but I believe the basic principle is sound. Link to comment Share on other sites More sharing options...
MajinVegeta Posted March 23, 2003 Share Posted March 23, 2003 When you say "exicted" do you mean "unstable"? Fascinating though! Link to comment Share on other sites More sharing options...
Dudde Posted March 23, 2003 Share Posted March 23, 2003 right...I'm not far enough to answer the question but I can still understand the answer... cool^_^ I didn't know that... Link to comment Share on other sites More sharing options...
Michael F. D. Posted May 10, 2003 Share Posted May 10, 2003 Originally posted by fafalone A little beyond? It's way beyond. It has to do with the interactions between photons and electrons in the atoms... especially unpaired electrons. The Colour of the material is defined by particle from Bosons group and is named Gluon according to Standard Model. Is it not been denyed yet? Link to comment Share on other sites More sharing options...
Radical Edward Posted May 11, 2003 Share Posted May 11, 2003 Originally posted by Michael F. D. The Colour of the material is defined by particle from Bosons group and is named Gluon according to Standard Model. Is it not been denyed yet? that is the inter quark force. it is just a tag because it is conveneient and there are some parallels, but there is nothing to do with the colour of an object as you can see it. Link to comment Share on other sites More sharing options...
Michael F. D. Posted May 11, 2003 Share Posted May 11, 2003 Originally posted by Radical Edward that is the inter quark force. it is just a tag because it is conveneient and there are some parallels, but there is nothing to do with the colour of an object as you can see it. Seems you do not believe that a particle can to carry information on colour. I do not believe too. The Colour this is direct effect of the phenomena of the resonance. The Resonance explains in the same way reflection, diffusion and transparency of the material for EM radiations and the light in particular. My explanation in attachment. ss & ps.txt Link to comment Share on other sites More sharing options...
Radical Edward Posted May 11, 2003 Share Posted May 11, 2003 far from it, particles do have colour, however it is the electrons that deal with the electromagnetic interaction. There is more documented evidence and modelling that you can shake a stick at. Try explaining and quantifying the sodium lines, Lamb Shifts and so on in any other way. Link to comment Share on other sites More sharing options...
JaKiri Posted May 11, 2003 Share Posted May 11, 2003 Originally posted by Radical Edward far from it, particles do have colour, however it is the electrons that deal with the electromagnetic interaction. There is more documented evidence and modelling that you can shake a stick at. Try explaining and quantifying the sodium lines, Lamb Shifts and so on in any other way. And the existance of lasers. Oh, and emission spectra, but that's pretty much the same thing. As is every example of colour, except the flavour of gluons. Link to comment Share on other sites More sharing options...
Michael F. D. Posted May 12, 2003 Share Posted May 12, 2003 Originally posted by Radical Edward far from it, particles do have colour, however it is the electrons that deal with the electromagnetic interaction. There is more documented evidence and modelling that you can shake a stick at. Try explaining and quantifying the sodium lines, Lamb Shifts and so on in any other way. The purpose of any model -an imitation of the object or phenomena. It is not requires a description of the deep structures of each its element. If stick, mentionning by you, can be the model of nave in some situation, that there is no need build in stick all a details of real nave. It is enough that behaviour of the stick exactly corresponds to behaviour of the nave in given situation. Link to comment Share on other sites More sharing options...
Radical Edward Posted May 12, 2003 Share Posted May 12, 2003 Originally posted by Michael F. D. The purpose of any model -an imitation of the object or phenomena. It is not requires a description of the deep structures of each its element. If stick, mentionning by you, can be the model of nave in some situation, that there is no need build in stick all a details of real nave. It is enough that behaviour of the stick exactly corresponds to behaviour of the nave in given situation. It is indeed true that you don't need an atomistic model to calculate many observed phenomenon, however this is a completely different position from yours. you more or less advocate rewriting the entire model (into one hthat you have not even shown fits) in order to do what? exactly? your model does not describe anything useful at all, and doesn't even have a mathematical foundation to it, and from what I can see, doesn't even have any basis. Maxwell's equations are already beautiful and elegant enough Link to comment Share on other sites More sharing options...
Michael F. D. Posted May 12, 2003 Share Posted May 12, 2003 Originally posted by MrL_JaKiri And the existance of lasers. Oh, and emission spectra, but that's pretty much the same thing. As is every example of colour, except the flavour of gluons. All from mentionned by you phenomenas this is a manifestation of resonance. In the "laser" abbreviation " r " has importance "resonance". Can you denies this too? The function of PS in offered model can be executed via a wave functions of electrons (electronic cloud of atoms) combined in group . BTW, COLOUR of INVISIBLE particles this is a prominent invention. Does it means the radio waves has a color too? Whose the eyes allows to observe this phenomena? May you report the author's name? Link to comment Share on other sites More sharing options...
Michael F. D. Posted May 12, 2003 Share Posted May 12, 2003 Originally posted by Radical Edward It is indeed true that you don't need an atomistic model to calculate many observed phenomenon, however this is a completely different position from yours. you more or less advocate rewriting the entire model (into one hthat you have not even shown fits) in order to do what? exactly? your model does not describe anything useful at all, and doesn't even have a mathematical foundation to it, and from what I can see, doesn't even have any basis. Maxwell's equations are already beautiful and elegant enough Yes, they are. But I distrust what you can have image in the mirror or a landscape through the window's glass by means of Maksvell's equations only. Do not forget a colour, please. Will you try? Link to comment Share on other sites More sharing options...
fafalone Posted May 12, 2003 Share Posted May 12, 2003 Originally posted by Michael F. D. All from mentionned by you phenomenas this is a manifestation of resonance. In the "laser" abbreviation " r " has importance "resonance". Can you denies this too? The function of PS in offered model can be executed via a wave functions of electrons (electronic cloud of atoms) combined in group . BTW, COLOUR of INVISIBLE particles this is a prominent invention. Does it means the radio waves has a color too? Whose the eyes allows to observe this phenomena? May you report the author's name? a) The 'r' in 'laser' is for radiation. Light amplification by stimulated emission of radiation. b) What you think is color is nothing but a wave in the range that the human eye is sensitive to. Radio waves are the exact same thing, only in a wavelength range that our eyes are not sensitive to. Also consider infrared; this wave has a wavelength is above what our eyes can see, but not above what the eyes of some animals can see. Your model is incoherent and not applicable to the the properties of anything is this universe. Link to comment Share on other sites More sharing options...
superchump Posted May 12, 2003 Share Posted May 12, 2003 Originally posted by Michael F. D. Yes, they are. But I distrust what you can have image in the mirror or a landscape through the window's glass by means of Maksvell's equations only. Do not forget a colour, please. Will you try? LASER = Light Amplification by Stimulated Emission of Radiation oops wrong quote Link to comment Share on other sites More sharing options...
Michael F. D. Posted May 13, 2003 Share Posted May 13, 2003 Originally posted by fafalone a) The 'r' in 'laser' is for radiation. Light amplification by stimulated emission of radiation. b) What you think is color is nothing but a wave in the range that the human eye is sensitive to. Radio waves are the exact same thing, only in a wavelength range that our eyes are not sensitive to. Also consider infrared; this wave has a wavelength is above what our eyes can see, but not above what the eyes of some animals can see. Your model is incoherent and not applicable to the the properties of anything is this universe. a) Ok. The lasing medium between two mirrors this is a pure resonance box. A following quoting from http://science.howstuffworks.com/laser2.htm describes a process of resonance : "The first photon can stimulate or induce atomic emission such that the subsequent emitted photon (from the second atom) vibrates with the same frequency and direction as the incoming photon". There are no empty gaps between atoms in a solid material. This is seen at STM images of different surfaces. b) "The frequency of visible light is referred to as color" in that place. Visible only. Whatever the eyes- of people or animal. c) I am living in other Universe. Link to comment Share on other sites More sharing options...
JaKiri Posted May 13, 2003 Share Posted May 13, 2003 Originally posted by Michael F. D. a) Ok. The lasing medium between two mirrors this is a pure resonance box. A following quoting from http://science.howstuffworks.com/laser2.htm describes a process of resonance : "The first photon can stimulate or induce atomic emission such that the subsequent emitted photon (from the second atom) vibrates with the same frequency and direction as the incoming photon". There are no empty gaps between atoms in a solid material. This is seen at STM images of different surfaces. It's not a vibrationary effect. It's an effect that promotes the electrons into a higher shell ('excites them'). If there are no gaps between atoms, then define where an atom ends. Originally posted by Michael F. D. b) "The frequency of visible light is referred to as color" in that place. Visible only. Whatever the eyes- of people or animal. Yes? We call invisable waves things like gamma rays or radio waves. We don't call them 'green light'. Originally posted by Michael F. D. c) I am living in other Universe. Then stop posting in a forum in our one. Link to comment Share on other sites More sharing options...
Michael F. D. Posted May 14, 2003 Share Posted May 14, 2003 Originally posted by MrL_JaKiri Yes? We call invisable waves things like gamma rays or radio waves. We don't call them 'green light'. Yes. Is it not some thing that was said by me? Take a look at posts above once more. Then stop posting in a forum in our one. I'll stop posting when we'll be in one universe. This will happen when you agree that my universe much more corresponds to a real one. note: I don't mean you personally as well as this forum exactly. Link to comment Share on other sites More sharing options...
JaKiri Posted May 14, 2003 Share Posted May 14, 2003 That will be never, unless you stop believing that the colour of an object is independent of the gluon interactions. I mean, what? Link to comment Share on other sites More sharing options...
Radical Edward Posted May 15, 2003 Share Posted May 15, 2003 Originally posted by Michael F. D. Yes. Is it not some thing that was said by me? Take a look at posts above once more. you don't understand what they said. Just but Principles of Optics by Born and wolf, and that will teach you everything you need to know. Link to comment Share on other sites More sharing options...
Michael F. D. Posted May 15, 2003 Share Posted May 15, 2003 Originally posted by MrL_JaKiri If there are no gaps between atoms, then define where an atom ends. Even though in whole universe will be two atoms only under any distance between them, they form one string too. One atom always ends where another begins . Link to comment Share on other sites More sharing options...
greg1917 Posted May 15, 2003 Share Posted May 15, 2003 A combination of uzbek-ised english and some wierd physics has left me confused. what precisely is wrong with the following model - an electron undergoes excitation , and when the electron moves back to a lower energy level it emits a photon. that photon will have energy E, exactly equal to the difference in energy levels of the two electron shells the electron moved between. the photon with energy E also has a frequency f determined by E =hf. this is the reason why hydrogen emits light in bands of wavelengths - the lyman series of wavelengths is produced when electrons fall from any energy level at all to n=1. balmer n=2, paschen n=3 etc. is someone trying to say this simplistic, respected and proven model is not correct? Link to comment Share on other sites More sharing options...
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