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WHY IS THE SKY BLUE? by Miles Mathis for the world is hollow and I have touched the sky Abstract: I will show that the current explanation is upside down. In researching this topic, I was surprised to find two different answers from two of the top mouthpieces of current physics. The top answer on a Yahoo search is by Philip Gibbs at the University of California, Riverside 1. It is that blue light is bent more than other colors. Gibbs shows us this illustration: Problem there is that we can move the Sun a few degrees and switch that effect. Just take the Sun above the first guy and he sees an unbent blue ray. The other guy sees a bent red ray. Light must be coming from all directions, not just the direction of the Sun, so this illustration is more than useless, it is misleading. Gibbs then shows it is air molecules, not dust, that do the bending, and he tells us that Einstein calculated in 1911 the scattering by molecules. These equations of Einstein are said to be “in agreement with experiment.” We are told, “the electromagnetic field of the light waves induces electric dipole moments in the molecules.” Gibbs then asks the million dollar question: “Why not violet?” If short wavelengths are bent more than long, then violet should be bent even more than blue, and the sky should be violet. He says it is due to the cones in our eyes. He shows the figure here and says that violet light stimulates red as well, making us see blue. The second top answer is from NASA, and is for kids. I would leave it be for that reason, except that the third 2 and fifth and sixth top answers are strictly the same as this one. All these answers are glosses of the only slightly longer and fuller answer at Wikipedia, which is fourth only because it is titled “Diffuse Sky Radiation.” That answer is that the blue sky is caused by Rayleigh scattering from molecules. Molecules scatter short wavelengths more than long wavelengths. The Wiki answer is the fullest I found on the web, but even it is short, without the usual attempts to misdirect with large amounts of math or complex theory. We are sent to the page for Rayleigh scattering, but we get one equation and then the whole theory: “the shorter wavelength of blue light will scatter more than the longer wavelengths of green and especially red light, giving the sky a blue appearance.” Wiki doesn't even bother to spin some yarn to explain “why not violet.” So let's look at this theory, such as it is. We already have two theories, although they seem to be similar or equivalent at a first glance. Gibbs' theory is that since red light is bent less, it never reaches the ground except near sunset. We get this impression from his illustration, although he never states it explicitly. It is slightly preferable to the scattering hypothesis and the scattering illustration, since it begins to address a smart kid's question: “If red is scattered less, wouldn't it just reach the ground directly, with more intensity?” So Gibbs draws bending instead of scattering. You see Gibbs has a few dormant scruples left, which makes him try to tweek the horrible answer he has been given from above. He also tries to answer the “why not violet?” question, although he clearly isn't up to it. His own figure, from eyeball physiology, shows in technicolor detail that the green receptors are also stimulated at violet wavelengths, so why talk about the red and ignore the green? He isn't making any sense. Even if the red were stimulated while the green were not, you still can't build blue from violet plus red, at least not according to the current model. Since the retina is not white, you can't stack these red and violet responses to get blue. That would require red canceling the red in violet. But if the eye is seeing both red and violet, that will make the violet more red, not less red. You can't make violet into blue by adding red in paint mixing, CMY, or RGB. The current model is an RGB model, and when crossing violet light and red light on a white background, you don't get blue. In RGB, you cross red and blue to get magenta. Just the opposite of his implication. But all this is moot, since his figure shows a green response, too. We need to mix red, green, and violet, to address his logic. In RGB, that should give us something quite near white. In CMY, it would give us something nearer black. His whole explanation of “why not violet” is a wash, and he would have been better to come up with a different dodge. Gibbs' semi-honesty also comes through in his ability to admit that violet is not lacking in the sky. Some have tried to answer “why not violet?” by claiming that our eyes are not as sensitive to it, or that it is absorbed by the high atmosphere, but Gibbs admits that it must be there, and that we must be sensitive to it, since we see it very well in rainbows. But back to the main question. Forget violet. Can bending or scattering explain “why not red?” Suppose that atmospheric molecules do scatter blue more or more often than red: does that explain the lack of red in the sky? No. To explain the lack of red, you need to keep red from hitting the ground, so you need to propose that it is bent so much it goes back up, or it is absorbed so much that it never comes down. Neither scattering nor bending does that or can do that, at least not with the current model of light. No smart schoolkid will be fooled by Gibbs replacing scattering with bending, since his question remains: “If red is either scattered or bent less or less often, shouldn't it just have a more direct path to the ground?” The answer Gibbs is trying to shield or prop up is the scattering answer, which uses Rayleigh scattering as the whole explanation of the blue sky. This is what we get from Wiki: The strong wavelength dependence of the scattering (~λ -4 ) means that blue light is scattered much more readily than red light. In the atmosphere, this results in blue wavelengths being scattered to a greater extent than longer (red) wavelengths, and so one sees blue light coming from all regions of the sky. Notice that Wiki has just interpreted the Rayleigh molecule equation in two different ways. In the first sentence, we are told that the wavelength dependence means that short wavelength light is scattered “more readily.” In the second sentence, we are told that short wavelengths are scattered “to a greater extent.” This leads us to ask, “Are the short wavelengths supposed to be scattered more often, or at a greater angle?” If we study the Rayleigh equation carefully, we find the answer is the angle, not the probability of being scattered. 4 2 2 4 2 I = I08π α (1 + cos θ)/λ R As you see, we have a representation of the angle, but no representation of the probability of being scattered. The constant α is the polarizability of the molecule, so it cannot vary with the wavelength of the light. The Rayleigh equation gives us an intensity of the scattered light, given an incoming wavelength. In other words, the Rayleigh equation requires the incoming light to be of one wavelength. We can only insert one wavelength into that equation at a time, as you see. We let red light hit a molecule, for example, and the equation tells us how intense the scattered white light will be. This is because the scattering turns the red incoming light into all colors (or, rather, no colors), depending on the angle of scattering. That is what scattering means. That is why the sky is bright instead of dark. If we subtracted out the color problem, we would explain the whiteness of the sky as due to scattering. That is why space is dark: no molecules are scattering, creating the whiteness. We can see this from Wiki, on the page for scattering. Scattering changes or destroys the original wave, as you see. You cannot scatter a wave and keep the wave at the same time. That is having your blue and eating it, too. Despite this, current theory assumes that a wavelength that is blue is scattered, remaining the same blue wavelength; that if anything it gains intensity from the Rayleigh equation; and that it is then reflected down (but not rescattered) by other molecules. Question: why do the first molecules scatter it and the second molecules just reflect it down? How do molecules know when to scatter and when to reflect? Amazing, really, that air molecules can redirect blue so many times without affecting it, but that air molecules cannot do that with red (except at sunset, of course). To see how dishonest all this is, we can study this figure at Wikipedia: Figure showing the more intense scattering of blue light by the atmosphere relative to red light They have created a figure to show what they want to show, although the Rayleigh equation doesn't show it. The figure shows more scattering of blue as a percentage of incoming light, and just in case you missed it, they make the upper part of the figure sky-blue and tell you one more time the conclusion: “Rayleigh scattering gives the sky its blue color.” They just need a manipulative soundtrack and a nude woman waving a magic wand and the propaganda would be complete.