Light, dark and clear

Discussion in 'The Cesspool' started by theorist-constant12345, Mar 1, 2015.

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  1. theorist-constant12345 Banned Banned

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    This is what I see, from absolute dark, to CBMR to infra red , to spectral magnitude and intensity, that gives sight, then from spectral magnitude and intensity decrease, back to infra red, back to CMBR.


    Explaining night and day, but the rotation of the earth is fast enough to only allow the stage to ever reach infra red resonance left that only ''charges'' the CBMR to enough intensity for other species to see at.
     
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  3. origin Heading towards oblivion Valued Senior Member

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    That is just more gibberish.
     
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  5. rpenner Fully Wired Valued Senior Member

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    Quantum electrodynamics is the best description of the observed behavior of electrons, light, similar and related phenomena. It reduces in appropriate limits to the 1865 Maxwell equations which describe in precise detail most classic optical observations.

    In vacuum, light is freely propagating massless phenomenon which carries momentum and energy. Thus it obeys:
    \( m = 0 \\ E^2 = (mc^2)^2 + (pc)^2 = p^2 c^2 \\ E v = c^2 p \quad \Rightarrow \quad \frac{\partial E}{\partial p} = v_{\textrm{group}} = \frac{c^2 p}{E} = c = v_{\textrm{phase}} = \frac{E}{p} \)
    Thus, in vacuum, there is no dispersion of a light signal with multiple components because both \(v_{\textrm{group}} \) and \(v_{\textrm{phase}}\) are the same.
    Light signals propagate unchanged through the vacuum, subject only to the limits of collamination -- even a very good laser pointed at the moon spreads out into a spot measured in kilometers so it takes a strong signal to be used over interplanetary distances.

    Visible light is that light which by non-destructive linear photochemistry potentially gives rise to the sensation of image for humans. For humans, this means light with a frequency of between about 400 THz to about 789 THz and wavelength in vacuum about 380 nm to about 750 nm (and roughly the same in air).

    When visible light is restricted by a narrow band-pass filter, we can see that the eye has a specific color sensation associated with illumination in every spectral band from about 400 THz to about 789 THz and these sensations we call the spectral colors. The eye's response to a single with multiple spectral components, testing reveals, is remarkably linear. Thus (to high precision ) all sensations of color are found on the convex hull (in some space) of the sensations produced by pure spectral colors at various intensities. As it turns out, this space has about 3 principle components -- so scientific measurement of color at this level of precision happens in an abstract three dimensional space. In this space red + green = yellow because that is the outcome of mixing equal amounts of pure spectral red and pure spectral green. But the yellow has a property distinct from color, it's intensity. Since 1 + 1 = 2, the yellow formed this way is more intense than the yellow formed by 1 measure of pure spectral yellow. So color and intensity are two dimensions in this three-dimensional space. Color may be broken up in various ways -- Yellow-verus-Blue and Red-versus-GreenishBlue (called UV in the YUV color space), or Cyan-versus-Orange and Green-versus-Purple (called IQ in the YIQ color space, part of the NTSC standard and why Apple II (1970's computer) hires display had such weird color choices available), or in analogy with polar coordinates, in terms of Hue (spectral colors and some colors between red and violet which are not pure spectral colors) and Saturation (percentage of the way from a central white point to pure hue).

    Computer representation of colors may be in terms of an abstract color model on in terms of reproduction using standard Red, Green and Blue phosphors or printing inks. Software built using knowledge of the human perceptual color model as revealed by experiment allows close reproduction of colors specified with some convention to be reproduced on various devices, and also allows precise paint color matching at hardware and paint stores.

    Human perception of the color of objects is based on autonomous estimation of illumination and the actual signal returned to the eye. Since fluorescent and incandescent illumination differs spectrally, while having similar whitish color, fabrics may take on unfamiliar hues in unfamiliar illumination. The most extreme common example is low pressure sodium bulbs which reduce the world to a monochrome in shades of yellow. This autonomous estimation of illumination may be fooled with a border about the object one is trying to estimate in which case the same gray square may seem perceptually different against a white or black background. Recently there was a black on light blue dress photographed with a blue background which caused many people to insist (over the claims asserted by the manufacturer) that the dress was gold on white.

    When objects absorb light of one frequency and then quickly emit light of a lower frequency, we call this fluorescence. Florescent colors are brighter at certain spectral bands than a pure white object would be. This is part of the reason why day-glo is another name fore these colors. Florescent bulbs are actually mercury bulbs which use the coating on the tubes to change some of the light to a whiter hue. When objects absorb light of one frequency and then slowly emit light of a lower frequency, we call this phosphorescence.

    In addition to visible light, there are many forms of invisible light. When we wish to be formal we refer to all of these phenomena collectively as electromagnetic radiation as per Maxwell's laws of electromagnetism, but here I simply use light. Our description of invisible light is also broken up by frequency band because the momentum and energy of individual photons are proportional to frequency (which has been known for over 100 years), and just as the reversible photochemical action of our eyes is frequency-dependent many elements of chemistry and physics are energy-dependent. So gamma rays can perturb nuclei, x-rays and ultraviolet (a different UV) can cause irreversible photochemical changes, infrared is associated with molecular freedom to vibrate, microwaves with molecular freedoms to rotate, etc.

    Spanning all of electromagnetism is the thermodynamic emission spectrum. Hot things glow. Black-colored hot things glow brighter than white-colored things. (not a typo!) Hotter things glow brighter than cooler things. The hue of successively hotter things starts red and grows oranger, then yellow then whitish then blue-whitish. The mathematical formulas for the spectrum and intensity of hot things has been known in detail for over a hundred years the mathematical ideal is called the blackbody spectrum. For objects which are not perfectly black, they achieve this only in approximation proportional to how black they are at every spectral band -- this is called their greybody spectrum.
     
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  7. Kristoffer Giant Hyrax Valued Senior Member

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    It saddens me that what rpenner just spent time writing won't even be considered by tc.
     
  8. theorist-constant12345 Banned Banned

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    collamination , is that why the telescope I was looking through tonight showed the planet I was viewing westerly from the UK was like a diffraction on a cd?

    and great post,and if you are saying the sun is black i also agree.
     
  9. billvon Valued Senior Member

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    No, he's not, any more than an operating incandescent light bulb is black. Both are primarily black body RADIATORS but they are not black.
     
  10. theorist-constant12345 Banned Banned

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    When Humans leave the immediate vicinity of their natural evolution environment the autonomous estimation of illumination and the actual signal returned to the eye can suffer from a synchronisation phase shift, the effects of this are experienced and reported by astronauts has seeing flashes of lights passing them by and also can be seen by the affects of motion by an observer and explained as motion blur.
     
    Last edited: Mar 4, 2015
  11. theorist-constant12345 Banned Banned

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    Oh ok.
     
  12. billvon Valued Senior Member

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    Again - no. Cosmic radiation caused the flashes seen by astronauts and had nothing to do with "synchronisation phase shift" or any of the other woo above.
     
  13. theorist-constant12345 Banned Banned

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    Astronauts state by observation a like ''shooting stars'' travelling past them , maybe flashes was a bad word to use, but either way their sight is losing timing synchronisation.
     
  14. billvon Valued Senior Member

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    No, there is nothing to synchronize to. Their retinas are being hit by cosmic radiation and they are reacting to it.
     
  15. rpenner Fully Wired Valued Senior Member

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    Probably not. You may be talking about chromatic aberration or you may have badly mishandled your telescope or you may not have been looking at the object you thought you were looking at.

    This link associates diffraction fringes more with out-of-focus images of stars, not planets.
    http://www.backyardastronomy.com/Backyard_Astronomy/Downloads_files/Appendix A-Testing.pdf

    Pictures and details or it didn't happen.

    A better mark of respect would be selective quotation for specific comments, not quoting the whole thing en masse.

    Well, as a matter of fact, the photosphere of the sun is highly ionized hydrogen plasma with some extras built on a scale of thousands of kilometers.
    Hydrogen plasma, like most metals, would reflect light cleanly if it had a polished boundary, but is pretty black when at a temperature of a few hundred kelvin with a rough or diffuse boundary. Because of the diffuse nature of the plasma-vacuum boundary and the great depth of the photosphere relative to the optical extinction depth, the photosphere is a nearly ideal black body at optical frequencies. We can't see further into the sun than it. It marks the last scattering boundary for optical frequency electromagnetic energy leaving the sun.

    An incandescent light bulb may be clear or white, but the filament (the glowing part) is approximately a black body.

    In both the above paragraphs, "black" is being used in a technical sense unrelated to human perception of color, but rather in the perfection of the coupling of the optical radiation frequencies to the thermal state of the object.

    Neither of these is perceptually black because they operate at temperatures of thousands of kelvins and have surface brightness brighter than any external light source you might have.
     
    Last edited: Mar 4, 2015
  16. theorist-constant12345 Banned Banned

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    I did not really have that many questions to ask, it sounds something like I have being saying, It is very posh lol and worded well.
    Your a scientist in real life aren't you?

    P.s I did not understand some of it though it sounded word salad to me.
     
  17. Dr_Toad It's green! Valued Senior Member

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    lol, yes, more than you'll ever dream of. lol.

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    lol
     
  18. Daecon Kiwi fruit Valued Senior Member

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    THIS is word salad.
     
  19. theorist-constant12345 Banned Banned

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    Yes it probably is, I should of just said lets talk about motion blur and how the blur is affect of motion making a timing offset of the light.
     
  20. rpenner Fully Wired Valued Senior Member

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    All the better reason for you to use the tools of selective quotation and clear anteceedents.
     
  21. Kittamaru Ashes to ashes, dust to dust. Adieu, Sciforums. Valued Senior Member

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    Unless you are traveling a significant fraction of light speed, you are NOT noticing "motion blur" because of any "timing offset of the light"...

    Motion blur is caused by our eyes ability to perceive only a limited number of frames (read, images) per second... and the brains ability to decode fewer still.

    Here's an experiment to try - have your wife/son/daughter/whomever stand in front of you. Turn your head and twist at the waist all the way to the left so you cannot see them, and have them hold their hand up with a random number of fingers extended.

    Turn your head and wasit as QUICKLY as you can to the right - see if you can accurately tell how many fingers are raised.

    Take it a step further - if you have a long street, put your car at one end of the street. Have someone in the middle of the length of road, with an object on either side of them, so you can only see them for a moment as you drive by.

    Have someone drive the car past them at, say, 60-75 MPH while they hold up a random number of fingers from both hands.

    See how accurate you are at judging how many fingers are held up.
     
  22. theorist-constant12345 Banned Banned

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    I am not sure, I am honestly lost for once, the way it is worded I am not accustomed too.

    anteceedents in what context?

    I read most of it as different from present information, a sort of unified theory?
     
  23. theorist-constant12345 Banned Banned

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    Why looking out of car side window at speed does the view then seem blur?
     
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