Sunlight, rainbow, color. You say everyone was talking about wavelengths, not frequencies. And then you quote Ethan referring to frequencies Ethan claimed that quantum makes frequencies of light discrete.
I pointed out that the discretization of frequencies of light is not due to quantization of light, it is due to boundary conditions, even true classically. Quantum discretizes the energies, not the frequencies. Please learn before responding!!!!! Bob: "Wow, thats wrong. What I said: "Bob, quantum theory quantises the light into packets.
No, a packet of light is one photon. It has an energy that depends on the frequency or wavelength equivalent statements. The mechanisms of emission by relaxation of an exited electron state in an atom is quantised by the mechanism of orbital energy states being quantised, but that's the mechanism for producing a photon, not about how photons act. If this were not the case, then we would not have black body radiation: the photons would only be allowed to be of set quantised energy states, and you would not get white light, but light of a mix of some set of distinctly disparate photons.
Given that the quanta if we supposed the CMB to be a conductive surface would be a wavelength of about 26 billion light years, that quanta is indistinguishable from continuous.
Yes wow, in your case of the CMB The frequencies are continuous, the energies are not That is my point. Bob, I take care to research the material before replying.
And nowhere in the books or material online did I ever come across what you say above. Frequency, wavelenght, energy.. But to say that ONLY energy is quantized and nothing else is new to me.
So please provide some source or formula or whatever which backs up your claim. Thank you. Since the energy is a constant times the frequency if the frequencies are continuous then the energy is continuous.
Bob knows but for some reason chooses to disregard others. Or he has forgotten but thinks he remembers. Or maybe he is too stuck in String theory that everything else became a sort of blur if he's the same Bob as in previous topics. Chelle on the other hand knows nothing and is just hooking other people to waste energy debating with him about pointless things. For a given frequency, the energy of light can take any real value classically, while it can only have discrete energy values in the quantum theory.
This is the new thing that quantum brings. This has nothing to do with whether the frequencies are continuous, that is a totally separate issue. Sometimes the frequencies are continuous, both quantum and classical, and sometimes the frequencies are discrete, both quantum and classical.
But for a fixed frequency, only quantum makes the energies discrete! If you can't understand this, then you don't understand anything about the theory of light. I'm amazed by all the people here trying to overturn quantum theory He's not talking about rainbow and color at all. He started by saying Ethan's sentence that photon's have discrete frequencies is wrong. I don't understand how that can be, but ok Sinisa, do you know what the word "discrete" means?
You said that a single photon has a discrete frequency and a discrete wavelength? This is meaningless. A photon has a frequency. In particular, for a fixed frequency, you can study the distribution of allowed energies. Now, note that response to a photon has to be perceived as different to be visibly different.
As a very crude analogue, the CCD on a digital camera has a quantum of "one electron ejected" but also a thermal noise. A signal producing one electron at a rate indistinguishable from noise is no difference at all. And the same goes throughout the entire CCD amplifier range until the pixel blooms or hits the maximum charge. Our systems for visual acuity also can only respond to certain colour ranges for each of the three colour receptors.
How many colors are really in a rainbow? White light through a prism. The Electromagnetic Spectrum. The Solar Spectrum. Harmonic nodes. But light, remember, is an intrinsically quantum phenomenon, and so if the energy of the photons coming from a source are finite and discrete, then so must be the frequencies and, interchangeably, the wavelengths coming from them.
It does not cover reflection nor oddities like spectral broadening or shifting of frequencies I. Which is entirely true too I assume the shades is correct, since bits per pixel is considered accurate for photographs and displays, I'm inclined to agree that this number is researched and accounted for. Absolutely true too. Just simple combinatory maths from any teenagers' maths class. Bob doesn't seem to have understood this. A Photon has one frequency you say?
Well that is a discrete number. Not a range of numbers like you get from, say, looking at the fourier transform of a musical note played on a real instrument. This is the new thing that quantum brings". What Ethan said is trivially true. OK Bob, let's get to basics. Frequency equals speed of light divided by wavelenght. Since sunlight is plychromatic, meaning is a mixture of different wavelenghts, it follows that there are photons with different wavelenghts.
Hence, photons with different frequencies. So in a given "sample" of sunlight you might have some photons which have wavelenghts in infrared, some in visible spectrum etc.. Each one of those has it's own wavelenght, thus it's own frequency. How can you separate wavelenght from frequency. That's what discrete means.
At least that's my take on it. You might have another, and would really like to hear it. But perception look at the title of the thread: How many colours are really in a rainbow of that is much more limited.
You mean that IS what he said, as you just quoted, while also noting that a spectrum with an exceedingly large number of discreet frequencies would be difficult or impossible to distinguish from a continuous spectrum in practice. Bob took issue with the statement of a discreet spectrum, claiming only energy is quantized. But quantized energy means for a finite amount of energy a finite amount of photons means a finite amount of frequencies in a spectrum.
As Ethan said. Try, like I said, reading the title of this thread. My whole point from the very beginning has been consistent and the same Ethan claimed, and it was echoed by many people including Wow, CD, Sinisa, that quantum gives a discrete frequencies, when it would be continuous classically. This is a fundamental misunderstanding of light.
So i corrected it. It is a shame that Wow can't understand basic physics. You claim all the same, but your quotes you say I made showing this had you say it was about QM and it was not about QM. See, SL, this is why I consider this to be chelle with another num de plum. The same half-assed english masquerading as thought. Most people on this blog disagreed with these points, and they are wrong. In fact Ethan claimed quantum makes the frequencies discrete, and many people parroted this false claim.
So your problem is that you're saying that the energy of light is discrete and that Ethan is saying that the frequency of light is discrete? This, however, doesn't mean that all light has to be. It means that a photon from electron shell transitions has a specific, discrete value for its frequency that depends on the energies of the two shells it is transitioning between. Has gaps in them. Not continuous.
Speaking of rainbows, I was looking through some old digital photos and realized that I'd photographed a rainbow with supernumerary arches, but I don't recall seeing the supernumerary arches when I took the photo. A few months ago I also saw a bizarre sundog - the arc was completed at the top and there were arcs below the images of the sun as well. Naturally I didn't have a camera Although the Fraunhofer lines were observed long ago, they are not observable in a rainbow or even easily observable with a prism for that matter.
If you go to the National Solar Observatories site you can get a false-color high-resolution spectrum of the sun as a JPEG image; the image will give you some idea of where the Fraunhofer lines and other dark lines not observed by Fraunhofer are and how they might affect what you see. Also keep in mind that instruments such as spectroradiometers were developed because the human eye is no good at measuring frequency and intensity of light; our eye detects one thing and our brains do something strange with that information - the end result is something which benefits our survival as a species but is not very useful for scientific measurements.
There re 3 colors if the rainbow, the primary colors, red, yellow, blue they mix together making secondary colors such as green orange indigo an violet, but I don't count the secondary colors because it is just primary colors mixed together. No there are three colour receptors in the male human eye. That is why we have "three colours", though our genetics allow four or even five colour sensors and for these people, there are more colours in a rainbow.
First of all, you got the primary colors wrong. Rainbows are additive colors, not subtractive ones. Your primary colors are the subtractive ones, applicable for instance to the mixing of paints. For additive colors, such as a rainbow or the computer screen on which you are reading this the primary colors are red, green and blue. Now, on to the second point. There is a difference between what really exists and what you perceive with regard to colors. For instance, if you additively mix red and green, you will get a color perceived by the human eye to be yellow.
If you excite sodium atoms, you likewise will get a color perceived as yellow. The two are very different, however. The light from the sodium atom is monochromatic. That is, it consists only of photons with a single wavelength. The situation of a rainbow is more similar to the sodium light than it is to the mix of red and green. Well, not really. The idea that the subtractive primaries are red, yellow and blue RYB is confusing and should not be taught.
It would be wrong to think that cyan and magenta are just fancy names for blue and red. It's shocking, but true: The names we've been using for our primary colors when it comes to coloring books and paint chips? Totally wrong. Other colors can be used as primaries, but they will not produce as wide a range of color mixtures. The reason behind these inaccurate terms? The magenta primary controls the amount of green light and, finally, the cyan primary controls the amount of red light.
The subtractive primaries do this by absorbing different amounts of red, green and blue, while the additive primaries simply emit different amounts.
It's all about controlling the amounts of red, green and blue light. Westland offers a scholastic example to illustrate the rampant misconception around primaries. You have to love the candor. The reason for the lack of rationale is that, as we've discussed, red, yellow and blue aren't the real subtractive primaries at all — magenta, yellow, and cyan are.
What you should teach is that there is a clear relationship between the additive and subtractive colour primaries. The optimal additive primaries are RGB.
The optimal subtractive primaries are cyan which is red absorbing , magenta which is green absorbing , and yellow which is blue absorbing. Now, there is no conflict between the two systems and, in fact, it can be seen that additive and subtractive primaries are almost mirror images of each other. So, if cyan, magenta and yellow are the real deal primaries when it comes to tactile objects, why does just about everyone on the planet still think the honor belongs to red, blue and yellow?
It seems intuitive because people believe the following: 1 That it is possible to make all colours by mixing together three primaries, and 2 That the primaries are pure colours that cannot be made by mixing other colours. Well, yes, according to Westland, the idea that three pure primaries can create al the colors in the world is totally false. If we use three primaries, we can make all the hues, but we cannot make all the colours; we will always struggle to make really saturated vivid colours.
Here's the thing: even though we're taught to think of red and blue as "pure" colors, they're simply not. Here's how to prove that: open an art program on your computer and create a red patch on the screen. Then print the patch using a CMYK printer. But we will get the biggest gamut of colours using CMY and that is why we can say that CMY are the optimal subtractive primaries just as RGB are the optimal additive primaries.
And as far as blue goes, it's not as pure as you think either. Red absorbs in the blue and green parts. The Four Colors Personalities.
Don Lowry originally selected theater as an entertaining way to acquaint people with the powerful insights of temperament. In order to involve the audience in the process, he developed the True Colors character cards. The cards offered a gratifying, hands-on experience in discovering their True Colors personality traits. Little did he know at the time, the simplicity of these cards would be key to the ease of use and lasting impact of True Colors.
Flip a switch — the light comes on. Simple as that, right? The same could be said of the True Colors Character Card Sort — on the surface it seems like a simple act, yet behind this simple process is decades of personality research and observation. Once you sort the cards into your unique personality spectrum your personality will take on a new light. The card sort is a deceptively simple, yet profoundly effective way to discover your unique personality and begin your exploration with True Colors.
And light combines colors according to the the additive mixing method, which uses red, blue and green as primary colors 3. So where does Sir Isaac come into this? In the 17th century, he was the one who realized that, when we break white light apart using a prism or rain drops , we get the visual spectrum of colored light otherwise known as the rainbow.
As you can see, in the visual spectrum, each color bleeds into its neighbors. But Newton decided we should probably break this spectrum up into chunks, so we could more easily talk about it.
But how many divisions should there be…? Seven is lucky. Or so those of us in Western Cultures have always been told. But why? We can trace the roots of this association back to the 6th century BC and a dude named Pythagoras 5. Now, Pythagoras loved numbers. And he loved applying numbers to real-world phenomena.
Noticing a pattern? Pythagoras did: his observations showed that 7 was a magical number that somehow connected disparate phenomena. He further saw it as the sum of the spiritual 3 and the material 4. Pythagoras also started a school, and the ideas he espoused grew into a philosophy called Pythagoreanism , based on mathematics and mysticism.
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