It is gratifying that this video have got many comments, showing real interest in the subject. To be sure, the optical demonstration documented therein is really thought-provoking. Plainly, it is a visualization of the inherent symmetries of classical geometrical optics. By the use of mirror-slits the inverted spectrum and "shadow-rays" become as self-evident as the ordinary spectrum and its light-rays. However, these spectra and their transforming shapes are, as Goethe pointed out, just images. What do they teach us about the nature of light, colour and darkness?
This video deserves millions of views. This mankind should finally see that the Newton's explanation of how the light produces the colors has absolutely nothing to do with the truth.
Professor, I congratulate you again on this impressive experiment. It is magnificent, beautiful, elegant, and above all, of impeccable logic. Thank you for it.
This is Goethe light theory 101 but it is like Lao Tse five element theory 101, a light year in the journey of intuitive intelligence; but my teacher of fifty years led me to you for further instruction, and boy, could she paint. so thank you so much for making this so enjoyable; now i would like to find a transcript of your script and get my teeth into it. wow. Goethe was such a contemplative, which no doubt was key to his extraordinary gift of discernment.
This is actually a sleight of hand that I am sure Pehr knows about. The front mirror also creates a Goethe spectrum (just like the rear mirror) and the two are superimposed. Result = the rays ARE diverging, but as they leave the area delimited by the ray they merge with all the other colors and form white, alternatively "new" rays of blue and red are continually entering the "beam" from the surrounding white. Putting that "beam" through another prism does not change anything: the "beam" already contains dispersing rays, and all a prism does is disperse the rays some more, without disturbing the complex hidden structure.
Yes, but what you get with this optical setup is not a superposition of two Goethe-spectra, but a superposition of a Goethe-spectrum and a Newton-spectrum with darkness at the position of green. Hence, what we see is a dark-ray which gets coloured by the magenta of the Goethe-spectrum.
@@PehrSall Thank you, but I am confused by your statement that the superimposition is of a Goethe and a Newton-spectrum. The rear mirror reflects a Goethe-spectrum (the Newton one passes through and can be seen in the darkness), so the front mirror should do the same. It is exactly like the rear mirror just in a different position. So why would it reflect a Newton spectrum "in front"? We can clearly see the Newton spectrum from the front mirror in the darkness (bottom left). To my eye (and understanding) the magenta ray from the rear mirror is mixing with the Goethe-spectrum of the second mirror. Then as the second spectrum disperses, the blue overlaps with yellow (creating white), and the red overlaps with cyan (creating white) leaving the middle as magenta. My guess is that If you put a prism in-front of the Goethe-spectrum after the first mirror, the colors will not break down into components - it will come out the other side intact. It's the slit that causes the "perception" of the split ie red+blue from magenta, by removing all the other colors (green)
GREAT demo! I have noticed that there is a special quality about reflected light. I see RGB as dark field primaries. CMY as light field primaries. and then there is a class artist call secondary - GOV. A peculiarity I have observed, for example, is that the difference between red and orange depends on the ratio of how much subtractive and additive aspects there are to the color. Red is M:Y at 2:1, while orange is M:Y 1:1. If I simply stack transparencies, I only get orange no matter the ratio. however, if I use colored transparencies and shine the light so that some of it is a reflection BACK through the transparencies toward me - then this involves a combination of additive and subtractive elements and I get a distinct red and orange at the ratios mentioned! - Sure would be fun to explore this with some of the equipment you have, but your are a bit far :(
On revisiting this video I have to say, this is a genius experiment. PerhSall, is it your's? One would predict a second Goethe spectrum through the second mirror, but all we get is a ray of magenta! I am not actually sure how newtonian physics WOULD explain this!
This is a great experiment however why conclude so hastily that the blackness is empty and “a void”? Put on a black Sweater and stand under the rays of the sun. The blackness is “magnetic” and will absorb the rays of the sun that it will then restore as heat. Black contains all radiant colors and holds on to them which is why it appears as “black”. I think Goethe wanted us to look at white and black as two complementary phenomena, equal in importance.
Goethe would say neither light nor dark contain spectra. Spectra emerge from the mixture of light and dark, so darkness is not an "all consuming nothing" as stated here ua-cam.com/video/vu_7uG6KlsU/v-deo.html
@OJ. Black and darkness is not the same. As you stand there in the sun, you will cast a dark shadow on the ground. It may look as a black surface colour, but doesn't come from absorption av light by the ground. It is just darkness. In this particular video we deliberately avoided absorption, by using mirrors. But I agree that a general theory of colour certainly has to consider selective emission and absorption of radiation by matter.
Melanin as a pigment reflects infrared. I've seen this (with infrared camera) for some "black" objects. This is outside the visible "spectrum," of course. [Thanks for wonderful demonstrations]
Darkness might be a real positive quality. Just like light is. Using a black object it is possible to reflect a shadow and get low intensity light emitted on the other side. There are many explanations for it!
Suppose the generated ray of magneta were deflected by a thin mirror that has a width which is smaller than the ray. If the ray were deflected into the darkness beyond the flux of dispersed white light would the ray cease to exist or would it just become invisble to the eye?
Modern optics and understanding of how eye receptors work will still be able to explain this phenomenon using the model based on Newton’s colour theory - however, this misses the point. That being the invitation to think in a totally new way about light and colour, and actually see what is happening.
Exactly - that's the point! Giving an explanation of a phenomenon means relating it to what is already known. But we still have reason to ask: what does the phenomeon tell us? How does it contribute to our understanding of the world we live in?
Great investigation. However, if the purple ray is a combination of red and violet light why doesn't the prism disperse the purple ray into red and violet? I understand that a white field is needed to produce the purple ray but why should a white field prevent the prism from dispersing the purple ray? Have you tried placing a prism in the path of a ray of shadow?
I have the explanation of these extraordinary experiments here: electricalspace.quora.com/THE-GREATEST-HOAX-IN-THE-HISTORY-OF-SCIENCE-PART-2-In-my-post-https-www-quora-com-q-electricalspace-THE-GREATEST-H
@@PehrSall I have been thinking a lot about this experiment and have decided that Goethe would have used mirrored slits to study of the coloured light at the boundries of the dispersed white light rather than study the colours within the dispersed white light as you did here. The coloured boundries which you intentionally conceal near the beginning of the video here, ua-cam.com/video/vu_7uG6KlsU/v-deo.html could be used to start a new investigation.
@@PehrSall also even if you can't see a light ray from a Goethe spectrum in the dark, that doesn't necessarily prove the ray can't exist in the dark . For example consider the situation where the trace of a goethe ray is clearly visible on the white card. Next imagine cutting out a section of the white card where the ray would cross. When the ray enters the gap it will appear to vanish and then reappear on the other side.
@@infra-cyan On the other side you will see a Newton-spectrum with black middle (where green is usually) this is the "purple-ray", now appearing as "black-ray". Likewise, if a green ray from a newton-spetrum is sent through a slit into a field of dispersed light, you will get a goethe-spectrum with white in the middle (instead of purple) and this green ray is now appearing as white ray. According to ray-optics all these four (purple. black. green. white) or one and the same ray, appearing under various conditions.
Well, magenta didn't exist in Goethe's times, so he adopted "purple". Already Newton called the result of additve mxing of the red an violet ends of the spectrum "various purples". In colorimetry we often speak of "the purple line" in the chromaticity diagram.
It is gratifying that this video have got many comments, showing real interest in the
subject. To be sure, the optical demonstration documented therein is really thought-provoking.
Plainly, it is a visualization of the inherent symmetries of classical geometrical
optics. By the use of mirror-slits the inverted spectrum and "shadow-rays" become
as self-evident as the ordinary spectrum and its light-rays. However, these spectra
and their transforming shapes are, as Goethe pointed out, just images. What do
they teach us about the nature of light, colour and darkness?
This video deserves millions of views.
This mankind should finally see that the Newton's explanation of how the light produces the colors has absolutely nothing to do with the truth.
this teaches us very many things.
What about the the rainbow? It is Newtonian colors reflected in light.
Great video, I love the visual demonstration.
Thank you, Gabriel! It was quite a job to make the video.
Yours Pehr
Thank you for your insight.
Professor, I congratulate you again on this impressive experiment. It is magnificent, beautiful, elegant, and above all, of impeccable logic. Thank you for it.
Gorgeous video. Thank you for the work everyone put into this!
Impressive video and experiments; thanks for this wonderful explanation of Goethe's Color Theory
This is Goethe light theory 101 but it is like Lao Tse five element theory 101, a light year in the journey of intuitive intelligence; but my teacher of fifty years led me to you for further instruction, and boy, could she paint. so thank you so much for making this so enjoyable; now i would like to find a transcript of your script and get my teeth into it. wow. Goethe was such a contemplative, which no doubt was key to his extraordinary gift of discernment.
Brilliant. Thank you for this.
This is actually a sleight of hand that I am sure Pehr knows about. The front mirror also creates a Goethe spectrum (just like the rear mirror) and the two are superimposed. Result = the rays ARE diverging, but as they leave the area delimited by the ray they merge with all the other colors and form white, alternatively "new" rays of blue and red are continually entering the "beam" from the surrounding white. Putting that "beam" through another prism does not change anything: the "beam" already contains dispersing rays, and all a prism does is disperse the rays some more, without disturbing the complex hidden structure.
Yes, but what you get with this optical setup is not a superposition of two Goethe-spectra, but a superposition of a Goethe-spectrum and a Newton-spectrum with darkness at the position of green. Hence, what we see is a dark-ray which gets coloured by the magenta of the Goethe-spectrum.
@@PehrSall Thank you, but I am confused by your statement that the superimposition is of a Goethe and a Newton-spectrum. The rear mirror reflects a Goethe-spectrum (the Newton one passes through and can be seen in the darkness), so the front mirror should do the same. It is exactly like the rear mirror just in a different position. So why would it reflect a Newton spectrum "in front"? We can clearly see the Newton spectrum from the front mirror in the darkness (bottom left). To my eye (and understanding) the magenta ray from the rear mirror is mixing with the Goethe-spectrum of the second mirror. Then as the second spectrum disperses, the blue overlaps with yellow (creating white), and the red overlaps with cyan (creating white) leaving the middle as magenta. My guess is that If you put a prism in-front of the Goethe-spectrum after the first mirror, the colors will not break down into components - it will come out the other side intact. It's the slit that causes the "perception" of the split ie red+blue from magenta, by removing all the other colors (green)
GREAT demo! I have noticed that there is a special quality about reflected light. I see RGB as dark field primaries. CMY as light field primaries. and then there is a class artist call secondary - GOV. A peculiarity I have observed, for example, is that the difference between red and orange depends on the ratio of how much subtractive and additive aspects there are to the color. Red is M:Y at 2:1, while orange is M:Y 1:1. If I simply stack transparencies, I only get orange no matter the ratio. however, if I use colored transparencies and shine the light so that some of it is a reflection BACK through the transparencies toward me - then this involves a combination of additive and subtractive elements and I get a distinct red and orange at the ratios mentioned! - Sure would be fun to explore this with some of the equipment you have, but your are a bit far :(
I am not sure I understand exactly what you report .. but it sound interesting ..
This was fascinating; thank you.
Beautiful presentation.
On revisiting this video I have to say, this is a genius experiment. PerhSall, is it your's? One would predict a second Goethe spectrum through the second mirror, but all we get is a ray of magenta! I am not actually sure how newtonian physics WOULD explain this!
excellent research
This was AMAZING! Thanks!
Quality is not quantity. Color is not wavelength.
well done demonstrtation - thank you! 🙏
This is a great experiment however why conclude so hastily that the blackness is empty and “a void”? Put on a black Sweater and stand under the rays of the sun. The blackness is “magnetic” and will absorb the rays of the sun that it will then restore as heat. Black contains all radiant colors and holds on to them which is why it appears as “black”. I think Goethe wanted us to look at white and black as two complementary phenomena, equal in importance.
Goethe would say neither light nor dark contain spectra. Spectra emerge from the mixture of light and dark, so darkness is not an "all consuming nothing" as stated here ua-cam.com/video/vu_7uG6KlsU/v-deo.html
I agree.!
@OJ. Black and darkness is not the same. As you stand there in the sun, you will cast a dark shadow on the ground. It may look as a black surface colour, but doesn't come from absorption av light by the ground. It is just darkness.
In this particular video we deliberately avoided absorption, by using mirrors. But I agree that a general theory of colour certainly has to consider selective emission and absorption of radiation by matter.
@@PehrSall Indeed. A television screen is not black, but dark. Only when some of the pixels are turned on does one see black.
Melanin as a pigment reflects infrared. I've seen this (with infrared camera) for some "black" objects. This is outside the visible "spectrum," of course. [Thanks for wonderful demonstrations]
Darkness might be a real positive quality. Just like light is. Using a black object it is possible to reflect a shadow and get low intensity light emitted on the other side. There are many explanations for it!
excellent. Bravo and thank you.
Suppose the generated ray of magneta were deflected by a thin mirror that has a width which is smaller than the ray. If the ray were deflected into the darkness beyond the flux of dispersed white light would the ray cease to exist or would it just become invisble to the eye?
Thank You
brilliant
Modern optics and understanding of how eye receptors work will still be able to explain this phenomenon using the model based on Newton’s colour theory - however, this misses the point. That being the invitation to think in a totally new way about light and colour, and actually see what is happening.
Exactly - that's the point!
Giving an explanation of a phenomenon means relating it to what is already known. But we still have reason to ask: what does the phenomeon tell us? How does it contribute to our understanding of the world we live in?
Very good. So there are 2 spectrum, added they create white, subtracted they create black?
well - projected spectra cannot combine subtractively, only additively.
How do you 'phase out' the boundaries of the white beam?
By making the white surface black on the sides of the light path
Great investigation.
However, if the purple ray is a combination of red and violet light why doesn't the prism disperse the purple ray into red and violet? I understand that a white field is needed to produce the purple ray but why should a white field prevent the prism from dispersing the purple ray?
Have you tried placing a prism in the path of a ray of shadow?
I have the explanation of these extraordinary experiments here:
electricalspace.quora.com/THE-GREATEST-HOAX-IN-THE-HISTORY-OF-SCIENCE-PART-2-In-my-post-https-www-quora-com-q-electricalspace-THE-GREATEST-H
Along the ray you have white minus green = purple
@@PehrSall I have been thinking a lot about this experiment and have decided that Goethe would have used mirrored slits to study of the coloured light at the boundries of the dispersed white light rather than study the colours within the dispersed white light as you did here. The coloured boundries which you intentionally conceal near the beginning of the video here, ua-cam.com/video/vu_7uG6KlsU/v-deo.html
could be used to start a new investigation.
@@PehrSall also even if you can't see a light ray from a Goethe spectrum in the dark, that doesn't necessarily prove the ray can't exist in the dark . For example consider the situation where the trace of a goethe ray is clearly visible on the white card. Next imagine cutting out a section of the white card where the ray would cross. When the ray enters the gap it will appear to vanish and then reappear on the other side.
@@infra-cyan On the other side you will see a Newton-spectrum with black middle (where green is usually) this is the "purple-ray", now appearing as "black-ray". Likewise, if a green ray from a newton-spetrum is sent through a slit into a field of dispersed light, you will get a goethe-spectrum with white in the middle (instead of purple) and this green ray is now appearing as white ray. According to ray-optics all these four (purple. black. green. white) or one and the same ray, appearing under various conditions.
THE COLOR IS MAGENTA, NOT PURPLE.
Well, magenta didn't exist in Goethe's times, so he adopted "purple". Already Newton called the result of additve mxing of the red an violet ends of the spectrum "various purples". In colorimetry we often speak of "the purple line" in the chromaticity diagram.
@@PehrSall fair enough, thanks for the background.