Into Unscientific Chapter 321

  In the activity room.

   Seeing someone raise their hands to speak, Xu Yun smiled slightly, ready to ask the other party to express their opinions.

  In this kind of occasion, regardless of whether the speech is right or wrong, the attitude should be encouraged.

  But after seeing the face of the member who raised his hand this time.

  He was taken aback for a moment, the words he was going to say stopped at the corner of his mouth, and he subconsciously looked at Lao Tang from the corner of his eye.

  This member is a well-proportioned young man with a shawl of blond hair, a high nose bridge, and good facial features.

  Even in terms of oriental aesthetics, this person is handsome.

  The other party's name, Xu Yun, was also well remembered, and it was called Ralph Ashley.

  However, Xu Yun was able to memorize this name, neither because the other party had any amazing achievements later, nor because the name had the same pronunciation as a little movie actor named Aishili in later generations.

   It's because this person's 'identity' is too special.

   Mentioned earlier.

   There is only one direct reason why Frederick Agar Ellis ran against Lao Tang for the president of the Student Federation:

  Ellis's favorite roommate in the dormitory, someone who is the number two in the mathematics department all the year round, is pursuing Lao Tang, which led to the endless situation between the two.

   That's right.

   That person is.

   Ralph Ashley. (True fact, the reference is "Age of the Earth: Lord Kelvin's Model", author Joe D. Burchfield, Oxford Press, page 47 of the 93rd edition has the original picture of the quoted letter, but Lao Tang has never run for president in history)

  A love triangle between three men.

Of course.

  Of the three, Lao Tang's orientation is normal. He later married a girl named Margaret, and he is an unlucky guy who was targeted by male ketones.

   On Pluto Night three months ago, Ralph Ashley was naturally there to cheer.

   And submitted an application for membership early.

  Actually, at the beginning, Xu Yun didn't want to call Ralph Ashley into Gewu Club.

  Naihe had made a lot of efforts in the preparation process of the calculation team before, including many follow-up matters, which were quickly resolved by relying on his contacts.

  In addition, Xu Yun had chatted with this person several times, and felt that the other party did not show any strange attributes in normal times, so he discussed with Lao Tang to include him in Gewu Society.

  Ralph Ashley's performance these days is still not bad, but when he speaks, Xu Yun will more or less reflexively think of Lao Tang

   Then he took a deep breath and adjusted his emotions to normal.

   Turning his head, he said to Ralph Ashley:

   "Senior Ashley, what do you think?"

  Ralph Ashley stood up when he heard the words, with a solemn expression coupled with a handsome appearance, he couldn't tell that this was a Chen Yuanyuan type of 'disaster':

   "Student Luo Feng, I do have some ideas that I'm not sure are correct, and I hope you can give me some advice."

  “In my opinion, since we want to verify the speed of light in the direction of ether motion and the speed of light measured in the direction perpendicular to the motion, the first thing we need to determine is the choice of light source.”

   "This light source must not be too large, and at the same time, various properties must be known and controllable, so I recommend using a sodium light source."

  Xu Yun nodded in affirmation.

  In fact, in the experiment he designed or transported, the most suitable vacuum tube light source.

   But at the moment Ralph Ashley doesn't know that Faraday has already worked out this thing, and it is very good to think of a sodium light source.

  Students of future generations who often mix labs should know it.

  Sodium light source is an experimental light source in optical basic instruments and measurements.

  It has double lines with two wavelengths of 589.0 and 589.6, and the color is relatively bright.

   When the skill level is low.

  Sodium light source is the most readily available monochromatic light source.

It is clear.

  This handsome guy who doesn't know whether it is 0 or 1, has a good knowledge reserve in natural science.

  So Xu Yun paused and asked again:

   "Senior Ashley, besides the sodium light source, do you have anything else to add?"

  Ralph Ashley smiled slightly, glanced at Lao Tang who was sitting beside him calmly, and said:

   "The second point is"

  "If the ether exists. I mean it exists, and the propagation of the speed of light in the ether obeys the Galileo velocity superposition principle."

   "Then the instrument we designed must have two optical path directions in the experimental coordinate system."

  This time, not only Xu Yun, but also other members in the audience nodded together.

  Galilean velocity superposition, which is one of the core principles of classical physics.

  Assuming that the ether is at rest relative to the sun, then what is moving is the instrument—and its moving speed is the earth's revolution speed.

   Finish these.

  Ralph Ashley also frowned slightly, and spread his hands neatly. To Xu Yun said:

   "Student Luo Feng, that's all I can think of. As for other steps, I don't have a clue."

  Xu Yun applauded upon seeing this, and praised:

   "It's okay, Senior Ashley, what you've done is already very, very good."

  Xu Yun's words are indeed not polite. If he can think of the first two points, Ralph Ashley's ability is already worthy of his second grade in the mathematics department.

   Then Xu Yun turned around and drew a small dot on the original position of the earth.

  The English word for sodium is marked to indicate that this is a sodium light source.

   Then draw an arrow from the light source, representing the light path, which is divided into two directions in a certain area.

  Draw these.

  He put down the chalk again, looked at the audience, and asked:

   "Students, besides the above two points, do you have any other ideas?"

   "This is not a classroom, everyone can speak freely."

   Hearing Xu Yun's words.

   buzz buzz—

  In the activity room of more than thirty people, there was a sound of discussion like a jumping egg.

   "I think it is possible to add a lens to the left optical path?"

   ".Isn't it suitable, you want to disperse the color?"

   "How about adding a little door-like switch here?"

   A few minutes passed.

  Hubert Airy raised his hand, the expression on the face of the son of the director of the Greenwich Observatory was a little eager, as if he had thought of a feasible method:

   "Student Luo Feng, here!"

   "Please tell me, Airy."

  Hubert Ally stood up from the audience with a whoosh, and said quickly:

   "Beam splitter, student Luo Feng, I think there must be a beam splitter!"

   As he spoke, he straightened his left index finger horizontally, indicating the path of light.

  The palm of the right hand was bent outward forty-five degrees, signaling:

   "Look, the light moves from left to right. Since it is a point light source, there is no fork."

   "So we can place a beam splitter on the right side of the light path to split the light path into two beams of light that are perpendicular to each other."

   "In this way, two beams that meet the experimental requirements are formed!"

   Hear about his designs.

   Before Xu Yun could make a sound, another boy asked first:

   "Then Airy, what happens after the light is divided? How do we observe or calculate the difference between the two beams of light?"

  Hubert Airy was taken aback when he heard the words, opened his mouth, and he couldn't help hemming and hawing:

   "There should be some kind of phenomenon, right?"

  The questioner did not let him go, but asked:

   "Then what phenomenon are you talking about?"

   Hubert Airy is silent.

   I can see it.

  This young man also raised his hand in a flash of thought. Although his train of thought was fine, he obviously only thought about the first half and was eager to show off.

  But after all, Hubert Airy has a good relationship with Xu Yun, and his father, George Biddle Airy, also helped in the night of Pluto.

   Therefore, Xu Yun took the initiative to help Hubert Airy out of the siege:

   "Ahem. Let me say a few words."

   "Although Airy didn't put forward a complete idea, the idea of ​​the beam splitter is very good."

   Then he picked up the pen and prepared to draw a diagram on the blackboard:

   "Actually, we only need to add two reflectors at the end of the two branched light paths."

   "Then place an observation screen on the other side of the vertical light path, and you can see it on it."

"Okay, I get it now!"

   As a result, Xu Yun hadn't even finished writing, when a figure sprang up from his left hand, and said excitedly:

   "It's interference, it's interference fringes! Am I right, Mr. Luo Feng?"

  Although Xu Yun didn't see the face of the interrupter clearly, Xu Yun was so familiar with the voice that he couldn't be more familiar with it.

   Looking at the more than 30 people in the classroom at the same time, there is only one person who can call him 'Mr. Luo Feng':

  The protagonist of this dungeon is the future Fu Qingwuwei Xubo Taishang Cihuang Daojun, a classmate of Mai.

  Seeing that Maimai seemed to have an idea, and his posture was more confident than Hubert Airy, Xu Yun suddenly had another thought in his mind:

   or

  Try to what extent can wheat be considered?

   After all, I realized that now, although Mai Mai kicked history forward a few times by relying on a few "Ah Lie Liai", Xu Yun has never seen Mai Mai actually design a complete experiment.

   This is indeed a pity for Xu Yun who likes to get achievement points when playing games.

   Now that I have an opportunity, how can I let it go?

  So he turned around, beckoned to Mai, and signaled him to come to the podium:

   "Come, come, I'll give you the pen, and you write."

   Mai Mai walked to the stage in a naive manner, took the chalk, and confirmed to Xu Yun:

   "Mr. Luo Feng, do you really want me to write it?"

  Xu Yun stepped aside and made a gesture of invitation:

   "Start your show."

   Seeing this, Maimai no longer hesitated, took a step in the middle, and began to write on the blackboard:

   "As you can see, the light emitted by the point light source will be split into two beams after passing through the beam splitter."

   "Well, for the convenience of description, let's call it beam 1 that travels horizontally to the right, and call it beam 2 that is refracted to the top of the blackboard."

   "Here's what I think."

   "We can place a reflector at the end of the two light beams. In this way, just like Mr. Luo Feng measured the speed of light back then, the two rays of light will reflect after hitting the reflector and return to the beam splitter in the direction they came from."

   "Then place another observation screen on the other side of the vertical light path. That is, under the blackboard."

   "Then the light beam 1 will first be reflected by the mirror M1, and then projected to the observation screen through the beam splitter."

   "Beam 2 is the same, reflected by mirror M2 and then projected to the observation screen through the beam splitter, forming interference with beam 1"

  Wheat's thinking is obviously much more complete than that of Hubert Alley. From the beginning of writing, the chalk he held has never stopped.

  Everyone in the audience, whether they are freshmen, seniors, or third-year graduates, watched wheat's demonstration attentively.

Da da d

  The entire activity room was silent, only the sound of chalk touching the blackboard and the sound of wheat explaining, even Xu Yun stepped aside:

   ". Then we let the experimental instrument rotate 90 degrees as a whole, then the time when beam 1 and beam 2 reach the observation screen is exchanged, so that the interference fringes that have been formed will move."

   "Continuous readings while the whole instrument is turning slowly, if our equipment is very accurate, it should be easy to measure the fringe movement."

  “. If the interference fringes move, the moving distance of the fringes can be measured from the experiment, and then the moving speed of the earth relative to the ether can be obtained, thus confirming the existence of the ether.”

   Mentioned earlier.

   Except for Bruch, most of the members at the scene are lovers of natural science.

  Although the purity and depth of knowledge they have mastered cannot be compared with that of their peers in later generations, they still have the basic scientific literacy.

  Therefore, as Maimai's blackboard writing gradually filled the blackboard, there were stunned expressions on the faces of members of the audience.

   Many people even took out their notes, and while recording the plan, they brought in numerical values ​​and started to calculate.

   Exactly.

   Presumably some students who are not ashamed have already seen it.

  Xu Yun led the experiment designed by Gewushe this time, which is one of the two famous dark clouds in physics in the 20th century

   Michelson-Morley experiment!

   This is a famous experiment conducted by Michelson and Morey on the Eagle side in 1887. Its idea is actually very simple, which is what Xu Yun said before:

  If there is ether, then when the earth passes through the ether and revolves around the sun, the speed of light measured in the direction where the earth moves through the ether should be greater than the speed of light measured in the direction perpendicular to the motion.

  So,

   Michelson and Morey created such an experimental device.

  The instruments used in this experiment are not complicated. From the top view, they are divided into four modules:

  The light source is located on the far left of the top view, and the light path is emitted from left to right—in actual operation, this direction should be consistent with the direction of the earth's revolution.

  A beam splitter is placed on the right side of the light source.

  Beam splitter, as its name suggests, is a mirror that can separate light, also called a beam splitter.

  It is classified from the nature of the material as a kind of coated glass, which is coated with one or more layers of thin films on the surface of optical glass.

  When a beam of light is projected onto the coated glass, the beam is divided into two or more beams through reflection and refraction.

  The spectroscope used in the Michelson-Morley experiment requires high precision. It can split the light into beam 1 that continues to the right, and beam 2 that goes vertically upward—the same is the top view.

   Then place two more reflectors at the ends of beam 1 and beam 2, and the light will go back the same way after arriving.

   Said earlier.

  When the earth is revolving, there will be an "ether wind" blowing head-on, and this speed is 30 kilometers per second.

  Therefore, in the beam 1 along the revolution direction, the propagation speeds of reaching M1 and returning from M1 are different.

  Assume that the speed of the earth is v, and the distance from the beam splitter to the reflector is d.

  Then the past and return speeds are c-v and c+v respectively, which is equivalent to headwind and SF Express.

  The round-trip time between the two is:

  d/(c-v)+d/(c+v).

  Because the light beam 2 is perpendicular to the direction of the earth's rotation, it will encounter the ether wind no matter whether it is going back or forth.

   Then the time is fixed:

  2d/√(c-v).

   In this way.

  The optical path difference between beam 2 and beam 1 reaching the observation screen is:

  c(d/(c-v)+d/(c+v)-2d/√(c-v)).

  With optical path difference, they will definitely produce interference fringes.

  Then as long as the experimental instrument is rotated 90 degrees as a whole, the time of beam 1 and beam 2 arriving at the observation screen is exchanged, so that the formed interference fringes will move.

  The amount of this change is also easy to calculate. I learned physics in high school, and it is △l=2dv/c.

   In this way.

  The number of moving stripes is △l/λ.

  The length of the optical arm of the interferometer designed by Michelson at that time was 12 meters, and the final fringe that should be moved theoretically was 0.37.

   As for the result.

   Let's put it this way.

   The purpose of Michelson Morley's experiment is to prove the existence of ether, and Michelson and Morley are also staunch supporters of ether theory.

  In the history of physics, this experiment is also known as the small Poisson experiment.

   Seeing the word Poisson, everyone must have guessed the final result.

   Exactly.

   The stripes don't say 0.37, it didn't move at all.

  The experiment that was supposed to prove the ether killed the ether instead.

  So this experiment is one of the major nodes in the history of physics, and it is also another experiment that those minke who deny the theory of relativity must mention in later generations:

  However, compared with the Fizeau flow experiment that serves as the "theoretical fulcrum" of Minke, the Michelson-Morley experiment often acts as a buffoon in the mouth of Minke.

  The standard terms generally look like this:

  【The reason why the Michelson-Morley experiment has zero results is because this experiment is completely wrong and it has no meaning】.

  This kind of treatment is a bit like Yuan Shu, the skeleton king in the Three Kingdoms. Basically, when you mention this person, you can't do without a sentence.

   But actually.

  These things questioned by Minke have been dissed by a lot of people in the history of physics.

  For example, after the results of the Michelson-Morley experiment were announced, many people thought that the experiment was not conclusive.

  For example, the famous Lorenz still had doubts about the negative results of the experiment.

  Rayleigh considered in a paper published in 1892 that "whether the ether on the earth's surface is absolutely stationary or relatively stationary" is still an unresolved issue.

   He found the negative results of the Michelson-Morley experiment "a real disappointment."

  Oh, by the way, there is also Lao Tang who was targeted by male ketones at the scene today.

  The Lord Kelvin did not believe this result, just like Liu Bei who learned of Guan Yu's death, shouting in his mouth, "Impossible, I am invincible in the world of ether".

  At the Paris International Physics Conference in 1900, he even directly urged Morey and another physicist named Miller to redo the experiment, otherwise he would sue them

   During the period from the publication of the results of the Michelson-Morley experiment to the publication of the theory of relativity by the old love.

  Scientists repeated the Michelson-Morley experiment an unknown number of times at different locations and at different times.

   And use various means to verify the experimental results, and the accuracy is continuously improved.

  But the result remains the same.

   The interference fringes seemed to be suppressed by the base of my ears, and I stood still.

   After discovering that the experimental results remained unchanged, the physicists began to look for the disadvantages of the experiment, but there was still no result.

It can be said like this.

  Throughout the history of physics, you can't find a few experiments like the Michelson-Morley experiment that the entire physics community spent 20 years trying to find bugs.

in this case.

  If future generations look for faults from some unknown substance or from a microscopic perspective, it would be better to talk about it.

  But those folk sciences are directly deducted from the words, such as why one-fifth of the optical path is missing, and there is no relative origin, etc. These have actually been studied by the physics community many times. (Taking complaints about Douyin's algorithm. I recently read a few Minke bloggers, and now the homepage is full of Minke. It really makes people feel high blood pressure.)

   Minke is really right in only one sentence, that is, the constant speed of light proposed by Lao Ai is indeed only a hypothesis rather than a principle.

   But the problem is that although this hypothesis has no real, conclusive experimental proof, it has not been defeated in the debate with other theories.

   At least in Xu Yun's view.

  After a hypothesis is generally accepted, when it is applied, it is actually no different from the principle.

  In many occasions, picking out words is a very boring behavior.

  It's like pure water and mineral water are two different concepts, but when you ask a friend to buy a bottle of mineral water, he bought a bottle of pure water, you tell him to buy the wrong water and try?

  True to say, friends will leave you sooner or later.

  The line of sight returns to reality.

  Looking at the dense writing on the blackboard, Xu Yun glanced at Mai Mai with a silly smile on his face.

  I couldn't help feeling a surge of emotion in my heart.

   As expected of being able to derive Maxwell's equations, the mathematical sensitivity is really too strong.

To know.

  Although the equipment in the Michelson-Morley experiment is simple, it is not easy to figure out the link of the change of the interference fringes.

   It can only be said that under the training of Xu Yun and Gauss during this period, the growth rate of wheat has reached an extremely terrifying level.

   Otherwise, based on Xu Yun's understanding of wheat.

  At least in the original history, the wheat in this period should not have been so pretentious—after all, he had only entered Cambridge for half a year, and he was just a youthful version of a preposterous one.

   But on the other hand.

  Mait's writing on the blackboard also saved Xu Yun some work, and many processes were even simpler than Xu Yun expected.

  So he patted Mai Mai on the shoulder, signaling the tool man to return to his seat, and picked the peach himself.

   Then he looked at the audience and said:

   "Students, as you can see, Maxwell's demonstration is perfect-yes, this is the experimental plan I originally prepared."

   "If there is anything to add, the spectroscope must be placed on a smooth marble slab, and the bottom is filled with mercury, so that the steering can be smoothly controlled."

   "Other than that, even if Mr. Fat Fish is reborn, there is nothing to add."

  The audience was silent for a moment.

   After a few seconds.

  Papapa—

   There was a burst of warm applause suddenly in the event room, and many people even had a look of pride on their faces.

  In this timeline, Xu Yun, a descendant of a fat fish, can make such an evaluation, which is basically no less than the later generations Pele and Manadona said at the same time that a certain player has the appearance of a football king.

   Wait until the applause dies down.

   Max Christian Friedrich Bruch, who was not too serious about watching the excitement, raised his hand again and asked impatiently:

   "Student Luo Feng, when can we start this experiment?"

  Xu Yun smiled when he heard the words, and made a gesture of calmness to him, and said:

   "Student Bruch, don't be too anxious. Although this experiment is simple, the equipment used is very demanding."

   "For example, a convex lens used to disperse the light spot to form an interference pattern, an interferometer cantilever with a minimum length of 12 meters, which can detect 0.01 times the wavelength change, etc."

   "The above equipment can be prepared within half a year, which is considered fast."

   "Not to mention that debugging also takes a certain amount of time, so my initial experiment time is probably around October this year."

  As Xu Yun said.

  The reason why Michelson in history found Morey to cooperate is because the equipment needed for this experiment is really super class.

  That Murray, whose full name is Edward Murray, is an expert in the construction of experimental equipment, and his skills are second to none at the end of the 19th century.

  But even if Morey took the shot himself, it took them four full years to get a lot of instruments.

  Current copy is influenced by Xu Yun, and the industrial productivity of optical equipment is close to 1900, which is higher than Michelson's era.

  At the same time, there is Avelyn, the ATM Ji Saqian, so it should not be difficult to complete the preparation within half a year.

Of course.

   The set of instruments prepared by Xu Yun is aimed at those authorities, but a simple interferometer can be set up inside the Gewu Club for the members to try first.

  Although the simple interferometer is easy to find some 'loopholes', it can more or less shake the confidence of these members in the 'ether' - otherwise, if you wait for half a year, some internal links may encounter resistance.

  So Xu Yun thought about it, and added another sentence:

   "Students, although a sophisticated large-scale interferometer takes several months, it is difficult to see the finished product in a while."

   "However, if you are interested, the association can make a set of simple experimental equipment for you."

   "This set of equipment may have some loopholes in theory, and the light arm is only about one meter. It can be done in about a week. I don't know if everyone is willing."

  Before the last word 'meaning' was finished, the audience murmured:

   "Of course!"

   "I want it, I want it, it doesn't matter if it's shorter, the light path is the same thickness anyway"

   "All right!"

   Three minutes later.

  Xu Yun's proposals were all approved.

   After all, for students these days, it would be nice if the association could provide opportunities for experiments.

  As for the concept of precision, at least before the experiment starts, they will definitely not care about it.

   As for after the experiment

  Probably he will pull up his trousers.

   After appeasing everyone's emotions.

  Xu Yun looked around the audience for another week, and looked at Hubert Airy:

   "Student Airy, I wonder if you still remember what I said to you earlier?"

   Hubert Ally blinked:

   "Ten points to Gryffindor?"

  Xu Yun glanced at this guy speechlessly, shook his head and said:

   "When you mentioned the light attribute before, I once told you—the second half of your sentence is actually wrong."

   "In addition to ether, that half of your sentence also includes another concept."

   "Although light is suspected to have wave-particle duality, it will only show one property in a fixed situation."

   "For example, Newton's bright spot, or the photoelectric effect."

  Hearing what Xu Yun said, Hubert Airy also remembered it:

   "Oh oh. I remembered, that's right, you said that."

  After speaking, he suddenly realized something, looked at Xu Yun in surprise, and said uncertainly:

   "Student Luo Feng, could it be?"

   "Besides interfering with the experiment, do you have other arrangements?"

  Xu Yun nodded to him, a playful smile suddenly appeared on the corner of his mouth, and said to everyone in the audience:

   "Students, how about your handicrafts?"

Chapter end