Into Unscientific

  Chapter 23 Colorful Light

   Friends who have studied physics should know it.

  Visible light has different refractive indices in different environments, such as glass, air, water and so on.

   These things have a unified title in concept, which is the medium.

  Nowadays, as the theoretical research of optics is gradually standardized, many junior high school students will also understand a truth:

  Light can propagate in a medium, and the propagation of light itself does not need a medium.

   But don't forget that Mavericks is in 1665, a time when optical research was still in its infancy.

   Therefore, Xiao Niu was able to think of the situation that the seven-color light may have different effects in different media in less than half a minute with just a few words from Xu Yun. This is completely a super class performance.

   Indeed.

The current Mavericks don't know that light itself is a boson, and it doesn't need any fermions to propagate—in this era, the top theory of optics for refraction is a mathematical equivalent derived by Snell, and it was in his death Nobody knew before.

   It will not be published as the famous Snell's law until Huygens and others review his manuscript in 1678.

  Before this, the equivalent formula was only deduced by Descartes in "Refractive Optics".

   And there is a lot of confusion here that no one can tell the truth, so now they are still sharing the honor of discovering the law of refraction of light.

  Thus, although Mavericks’ statement subconsciously covers the speculation that visible light cannot pass through a certain ‘environment’, this is a completely understandable situation—to be honest, can you imagine that the first layer has been blown up?

   Then looking at the small cluster of colorful lights on the ground, the Maverick suddenly thought of something again.

   He thought for a few seconds and asked Xu Yun:

   "Fat fish, since sunlight can be dispersed into seven beams of colored light, are these seven colored lights different lights?

   Also, in theory, these seven beams of light should be able to recombine into a beam of white light, right? "

  Xu Yun twitched the corners of his mouth, well, opening his mouth is another two fatal points.

  But at this time, he has gradually adapted to the abnormal thinking ability of this patriarch, so he quickly adjusted his mentality and said:

   "Sorry, Mr. Newton, I only know the answer to the latter question—as long as the conditions are right, the colorful light can recombine into a beam of white light."

   Mavericks was already in high spirits at this time, and his eyes rolled around:

   "Fat fish, you just said that a prism can also verify the phenomenon of dispersion?"

   "Yes, and the effect of the prism is much better than that of the mirror."

   "Then do it again with a prism!"

   Maverick looked around quickly, and said decisively:

  “I went into the house to look for the prism, I brought back a lot of these things from London a while ago.

  You are responsible for moving the table—the tea seat in the room will do, and it’s better to put it here. "

  Xu Yun nodded:

"clear."

   More than ten minutes later.

  A table with a diameter of about one meter, several prisms, and a black wooden board were placed next to the water tank one after another.

   Then Xu Yun stood up a prism, adjusted the angle skillfully, and made an OK gesture to Maverick.

   After a while.

  A cluster of long spectrums appeared on the cardboard behind the prism, and it was much clearer than the previous cluster.

  Xu Yun stepped aside when he saw this, and deliberately didn't make any representations, wanting to see what the youth version of the patriarch can do without any prompts.

  I saw Maverick walking to the table, leaning over to examine the spectrum carefully.

   Then he hesitated for a few seconds before picking up a black cardboard.

  Cut out a circle on it and place it on the outside of the prism, which is the direction where the light source comes from.

  A lot of sunlight is blocked by the cardboard, only a beam of circular light shines in through the small hole, and then.

   still formed a long spectrum.

   Seeing this situation, the Maverick immediately let out a soft "Huh".

   I don’t know if it’s because he wanted to confide in others, but he suddenly looked at Xu Yun again:

   "Fat fish, have you heard of Mr. Descartes' theory?"

  Xu Yun nodded and said:

   "Of course I heard about it, I visited it once at the University of Poitiers.

  Mr. Descartes believes that the color of light comes from the medium between the illuminant and the human eye, and has nothing to do with the light source.

  The color of light is not a characteristic of light, and the theory of light trace transformation is also proposed. "

   "That's not bad, but look here."

   Maverick held the cardboard in one hand, and pointed to the projected long spectrum with the other:

  "According to Mr. Snell's equivalence formula and Mr. Descartes' theory, after a circular beam passes through a prism, it should form a circular or elliptical spot.

  But after the dispersion occurs, the colorful light forms a long spectrum.

Could it be that.

  Is there a problem with Mr. Descartes' theory? "

   Maverick thought for a while before Xu Yun answered, picked up the cardboard and scissors again, and made a smaller hole.

  He placed the cardboard behind the first prism so that, using the circular hole, he could catch any beam of light in the colored band. (Xiao Niu painted this device at the beginning, (DOI) 10.1098/rsta.2014.0213, written by Xiao Niu himself, if you are interested, you can take a look, it is really a soul painter)

  Then Mavericks beckoned to Xu Yun, beckoning him to come forward:

   "Fat Yu, I will report the data, and you will record it."

  Xu Yun's pupils shrank slightly, knowing that Mavericks was swimming towards his final "net" step by step, but his face remained unchanged:

   "Yes, Mr. Newton."

   Then the two of them held a pen and paper, and the other began to measure the angle.

   "Red light, incident angle i60°, deflection angle β32.2°"

   "Orange light, incident angle i60°, deflection angle β37.4°"

   "Incident angle i60°, deflection angle β38.7°"

  After 20 minutes, the data of four groups and 28 times were recorded.

Different kinds of light have different refractive indices in optical glass. The deep-seated reason involves relative magnetic permeability μr and relative permittivity εr. These two constants need to be calculated by Maxwell’s equations in the medium, and then an intuitive material and light The interaction model, the equation of motion is induced by the linear dissipation force, and then its steady state is solved by the complex number method, etc.

  However, considering that it is inconvenient for PUA readers not yet on the shelves. Ahem, the content is too complicated, everyone only needs to understand the relevant conclusions from a macro perspective.

   After all, Mavericks didn’t have Maxwell’s equations in that era, did they?

   "Purple light 1.532 blue 1.528 green 1.519 yellow 1.517 orange 1.514 red 1.513"

  Looking at the fixed sets of data in front of him, Mavericks could not help but take a deep breath.

It is clear.

  The refractive indices of different colors of light are different and remain constant, and the properties of these seven colors of light are different.

   From this we can draw a conclusion:

  White light is indeed not a kind of pure light, it is composed of different lights.

   and this means

  He may be one point closer to the truth of the world.

at the same time.

   Maverick looked at the light that divided into seven and combined into one at the same time, and suddenly thought of something in his mind.

  I saw his chest suddenly heaved a few times, and he ran back to the house quickly.

   I have a bad cold, I will get an IV drip today, and I will change my face.

   After so much preparation, Xu Yun is finally going to start making trouble! !

  (end of this chapter)