Into Unscientific

"."

Handicraft?

Hearing the word that came out of Xu Yun's mouth.

There was a sudden silence in the conference room.

Many boys in the audience look at me and I look at you.

At the same time, a tacit smile rose from the corner of his mouth.

I know everything.jpg.

Seeing that the scene seemed to be developing towards a needlework exchange meeting, Xu Yun quickly coughed lightly, interrupting everyone's scattered thoughts:

"Ahem. Dear students, it may be that I am lacking in expression. Let me reiterate here."

"The handicraft work I'm talking about doesn't mean hand-grinding metal materials."

I don't know if it's an illusion.

Xu Yun always felt that after he finished speaking, there were a few disappointed sighs from the audience.

Which of Ralph Ashley's voices seems most pronounced?

Then he shook his head and adjusted his breathing.

Straightening his mind, he continued:

"Students, please put your attention back to our original sentence—although light is highly suspected of possessing wave-particle duality, its properties must be fixed under certain circumstances."

"Everyone knows that there are many situations that fit this sentence, even the prism dispersion experiments conducted by Sir Newton and Mr. Fat Fish."

Many members in the audience followed suit and nodded.

What Xu Yun said is common sense in today's era, which is so standard that it can no longer be standard:

The reason why a certain experiment can prove a certain property of light is because light exhibits the corresponding property in the experiment.

Don't look at the above sentence as it seems like nonsense.

When a concept is logically close to nonsense, it also represents the universality of the concept. In other words, the coverage has reached a terrifying height.

And what Xu Yun has to do next is to completely destroy the 'nonsense logic' constructed by these words.

Then he took another blackboard and drew a small dot on it.

Still mark the light source.

At the same time, an arrow from left to right is drawn on the right side of the light source, which means that the direction of the light path is from left to right.

Then turned around, looked at the audience, and asked:

"Students, can anyone briefly describe the double-slit interference experiment of light?"

This time, there were more hands raised in the audience, and there were about a dozen of them at a glance.

Xu Yun simply looked around, casually clicked on one of the bald boys, and said:

"This classmate, please tell me."

The boy with a bald head stood up, bowed slightly to the surrounding students in a very gentlemanly manner, and then said:

"As we all know, after Sir Newton proposed the wave-particle duality of light, although the physics community regarded it as a truth from a theoretical point of view, disputes arose on the proportional distribution of wave and particle properties."

"Some people think that the two properties of light are divided in half, and the number of scenarios expressed should each account for 50%."

"Some people think that although light has duality, the two are not divided, but are dominated by a certain quality."

"Based on this concept, the latter is divided into the wave majority and the particle majority, also known as the wave party and the particle party."

Xu Yun nodded slightly.

The 'summary of the previous situation' mentioned by the boy with the top is not difficult to understand.

Just like the harem texts of later generations.

Everyone admits the fact that there are multiple heroines, but when discussing the role of a certain heroine, many fans will often argue about it.

Some people think that everyone should live in harmony.

Some people think that the character they like is the female lead, and the others are bed warmers.

This is almost the case with the Bodang and Lidang parties in this timeline.

Afterwards, the bald boy touched the top of his sparse head, and continued:

"Sir Newton himself insisted on the particle theory in the early days, but after receiving the letter from Mr. Fat Fish, his attitude changed to neutral, and he discovered one of the strong evidences of the wave theory - Newton's bright spots."

"When Sir Newton passed away, the wave theory overshadowed the particle theory."

"Then in 1807, a young man named Thomas Young devised an experiment."

"He placed an opaque plate with two slits in front of the light source, through which the light or particles passed, and finally reached the photosensitive film, through which the physical properties were analyzed."

"If the film is forming interference fringes, it means that the waves are interfering."

"If the negative film has two light lines, it means that the particles are like small balls passing through the two cracks and hitting the photosensitive plate."

"In the end, interference fringes appeared on the film, which made the wave theory more popular, and the wave party had an absolute advantage."

"Someone even built a coffin for the Li Party and placed it at the door of Wilkins Joel, a well-known supporter of the Li Party."

"This situation lasted until last year, and it was brought back by the photoelectric effect demonstrated by classmate Luo Feng."

clap clap -

After the thankful man finished speaking, Xu Yun took the initiative to clap his hands.

Mentioned long, long ago.

Among the top ten physics experiments, there is one experiment that occupies two of the places.

This experiment is Young's double-slit interference.

Its design is just like what the bald boy said, relying on the cracks to observe the properties of light.

Simple and easy to use.

Even for two tons of breakfast money, you can repeat this experiment at home:

Get a laser pointer, a slightly stiffer piece of paper or thin plastic—grilled tinfoil is recommended, and use a razor blade to create two slits with neat edges that are close together.

Find another white wall, turn off the light and you’re done—well, experimenting here.

in the original history.

Yang's double-slit intervention once pushed Moxishuo to a desperate situation, almost lifting the Maverick's coffin.

I don't know if it is the inertia of history.

In this timeline of accelerated optical development, many well-known discoverers of theories or phenomena have been replaced.

But Thomas Young, a child prodigy, still designed this experiment just like the original history.

However, since Mavericks proposed the wave-particle duality of light long ago, the influence of Young's double-slit interference on optics has been weakened a lot.

Use the example of later generations of web articles to describe.

Probably because the work of the gods has become an ordinary ten thousand order.

Then Xu Yun thanked the bereaved man, motioned him to sit back, and said:

"Everyone, Yang's double-slit interference experiment is indeed very subtle, but I don't know if you have thought about such a problem."

"Suppose—I mean hypothetically, suppose we have the ability to tune a beam of light into individual photons."

"So what do these photons show up on the film?"

"Photon?"

Hearing the word that came out of Xu Yun's mouth, Hubert Airy in the audience subconsciously said:

"Since it is a single photon, it is of course two bright lines."

Hubert Airy's answer was met with no further objection this time.

Including the boy who questioned him before, everyone nodded in unison, taking it for granted.

Although Faraday is still humming and humming the chapters related to electronics, he has not yet officially released it to the public.

But it was mentioned earlier.

Since the discovery of elements, the scientific community has had a certain understanding of atoms.

So in the eyes of many people.

The "photon" referred to by the particle theory is a particle similar to an atom.

So after Xu Yun mentioned the photon, many members at the scene quickly gave the answer:

If it is possible to separate individual photons and emit them one by one, then there must be two bars appearing on the bottom plate—it is said to be a single particle, how could there be interference fringes?

Are you interfering with yourself?

This is obviously impossible.

Looking at the many members who had the same opinion in the audience, Xu Yun suddenly smiled:

"Students, if I tell you that a photon can pass through two slits at the same time and interfere with itself, would you believe it?"

As soon as Xu Yun said this.

There was no more than two seconds of silence in the activity room before a loud noise erupted.

"impossible!"

"Absolutely impossible!"

"Student Luo Feng, are you kidding me?"

However, it may be because Xu Yun has already said that the ether does not exist.

Although everyone's reaction was violent this time, it was not as bad as the first time.

Overall, it is maintained at a fairly manageable level.

It's a coincidence.

The person who was most excited this time was none other than Xu Yun's old acquaintance, Hubert Airy.

Having been exposed to telescopes since he was a child, his cognition and "belief" in light far exceeds that of other club members.

"Student Luo Feng!"

I saw Hubert Airy's face was flushed at this time, his hands were propped on the table, and he leaned forward, spittle was flying:

"Student Luo Feng, although I admire you and Mr. Fat Yu very much, and I also know that the Fat Yu family must have some untold secrets, but..."

"The possibility you mentioned, I dare say absolutely, absolutely does not exist!"

Then he looked around for a while, suddenly locked his eyes on Mai Mai, pointed to Mai Mai's waist and said:

"Let's put it this way, classmate Luo Feng, if what you said is true, I'll eat that ax on the spot!"

"."

Xu Yun twitched the corners of his mouth when he heard this, and couldn't help feeling sympathy for this stunned young man.

Boy, this ax looks like you're set

because

Even if a single photon passes through the double slit, the interference fringes are still obtained.

That's right.

The 'weapon' that Xu Yun took out as his trump card is the double-slit interference experiment of electrons!

The electrons here can be replaced by photons, and there is actually no difference between the two-at least in terms of phenomena.

mentioned above.

Among the top ten experiments in physics, the experiment designed by Thomas Young occupies the second place.

One of them is the standard Young's double-slit interference experiment, which is a macroscopic physics experiment that everyone can do for a few dollars.

The other is the double-slit interference experiment of electrons.

And this experiment has an alias, called

One of the scariest experiments in the history of physics.

Where is its horror?

Because it can be said to be the first "supernatural event" that human beings have officially encountered in scientific experiments.

However, about 50% of the ghosts here are real ghosts, and 50% are artificially added fake ghosts.

The idea of ​​this experiment is based on the Thomas Young experiment mentioned above, but it happened in 1961.

With the development of technology, the scientific community at that time already had machine guns that could emit electrons.

You can keep biubiubiu.

As a result, the final result is the same as Young's double-slit experiment:

The two rays of light passing through the double slit vibrate and intersect and interfere, the intensity of the peaks superimposes, and the positive and negative cancellation between the peaks and troughs.

In the end, there will be complex and beautiful zebra crossings on the screen, that is, interference fringes.

But Lipai refused to accept it, and put forward another request:

Let's do another experiment and launch the electrons one by one to see, it will definitely become two bars!

So they switched the electron machine gun to burst mode, ensuring that only one electron was fired at a time.

However, the result is still a zebra crossing.

In fact, if electrons or photons are really waves, there is nothing to say about the grain pie, so I am willing to bet and admit defeat.

But the problem is the individual electrons they emit!

To know.

According to wave theory, zebra crossings originate from the interference superposition between two wave sources generated by double slits.

That is to say, interference fringes appear, which means that it passes through two slits at the same time, instead of the probability model of passing left in the first second and right in the second second.

But in this way, it is contrary to the "single" of a single electron:

A single electron either passes through the left slit or the right slit, it is impossible to pass through both slits at the same time.

This is a mystery that remains unsolved to this day.

Of course.

Probably more famous about the double-slit interference experiment of electrons is another thing, the so-called third experiment:

In order to further observe the truth, the scientists installed two cameras in front of the screen, one on each side and one on the other.

Which side of the camera sees the electrons, it means which slit the electrons have passed through.

Again, electrons are emitted in burst mode.

The result is this:

Every time either the camera on the left sees an electron, or the camera on the right sees one.

One is one, and there has never been a case where an electron splits into half.

However, at this moment, something really weird happened:

The researchers suddenly discovered that the pattern on the screen quietly changed into two bars at some point!

Not watching with a camera.

The result is always a zebra crossing, photons are waves.

Watched with the camera.

The result is two bars, and the electrons become particles.

The results of the experiment depend on whether you look at the camera or not?

Does it sound creepier?

However, as a professional popular science work, here is one thing to popularize science:

The third experiment, the so-called experiment of adding a camera, is actually a thought experiment and has not been actually completed.

In fact, think about it.

Forget about the camera.

Even for other equipment and instruments, you want to directly see which slit the electron or photon passes through. Is this possible?

So no matter how you search on the Internet, you will not find any professional papers or experimental videos related to camera observation.

be honest.

The double-slit interference experiment of electrons is really scary, and its truth has not been cracked so far.

But the "horror" seen on the Internet today actually has the added color of a second creation.

At present, there are only the following three electron double-slit interference experiments that have been truly completed:

1. Early double-slit interference experiments.

This is a phenomenon that has been verified experimentally in the early days of the establishment of quantum mechanics. The more famous one is the electronic double-slit interference of Hitachi TV. (hitachi.com/rd/portal/research/em/doubleslit.html)

2. Wheeler's delay experiment.

In 1979.

John Wheeler, who once worked with Einstein, proposed an ideal experiment at a conference commemorating Einstein:

In order to abandon the interference of the observation behavior on the electron behavior in the electron double-slit interference, the observation is made after the electron passes through the double slit in a certain way.

Its idea is this:

A photon is emitted from the light source and passed through the half-mirror 1. The probability of the photon being reflected and transmitted is 50% respectively.

Afterwards, a total reflection mirror A and B are respectively placed on the travel path of the reflected or transmitted photons.

Make the two paths meet at C after reflection.

There are two detectors AB at C, which can respectively observe whether there are photons in the A path or the B path.

next.

If another half mirror 2 is placed at point C in front of the two detectors, photons can be self-interferenced.

After properly adjusting the optical path difference, the interference light in a certain direction (A or B) can be eliminated, and the detector in this direction can not always receive the signal.

At the same time, detectors in the other direction must always receive a signal.

The reason why this experiment is called the delayed choice experiment is that we can decide whether to place the half mirror 2 after the photon has passed through the half mirror 1 .

That is to say, after the light has decided to choose the wave nature or the particle nature, we will place the half mirror 2 to observe it.

The experiment was originally proposed as a thought experiment, but it was later verified by experiments, and this result was once published in Science. (DOI: 10.1126/science.1136303)

The ideal single-photon source has been published as early as 1974. The single-photon source in the above Wheeler experiment utilizes the defect of diamond N-V color center.

3. The quantum erasing experiment has also been verified experimentally.

The quantum erasure experiment is more complicated to talk about, which is the source of the so-called "the past can be changed within eight nanoseconds". (doi.org/10.1103/PhysRevA.65.033818)

Well, just these three -- maybe there are some other experiments that have been modified, such as C60 or something, but the core principles are the same as these three experiments.

At present, the closest achievement to the so-called "camera" should be a report made by the research team of the Physics Department of the University of Nebraska-Lincoln in 2011, but it is still far from a real camera. (doi.org/10.1088/1367-2630/15/3/033018)

Incidentally.

The so-called 'camera' pattern taken by the so-called camera on the Internet is actually a pattern of electronic interference made in 1988 by the team led by Neon's Akira Tomura. (doi.org/10.1119/1.16104)

The so-called experiment that can directly observe which slit the electron passes through is still a thought experiment, and no one has really been able to do it so far.

What is the "observation" that can really be done at present?

It is to install an electronic detector between the double slits. This detector cannot directly display images and observe the path of particles, and can only be used as a receiving screen.

When the detector switch is turned on, the light becomes particle-like;

When the detector switch is turned off, the light takes on a wave state.

It's like 'rain' falling from the sky, you have no way of knowing which cloud it fell from.

But you reach out, and it's rain.

If you don't reach out and see it fall with your eyes, what falls is a flower.

Everything depends on your observation, or interference.

So the electron or the double-slit interference experiment is actually one thing that is scary from the beginning to the end:

That's what liberal arts students don't understand at all.

Keke wrong wrong.

The scary part is that if you don't measure it is one result, if you measure it is another result-again, the measurement here is not the direct measurement of the camera, but the detector of the receiving screen.

That is to say, any information that can reveal the path situation and be recorded, will lead to the quantum collapse.

It's that simple.

We are professionals in dispelling rumors and popularizing science. (laugh)

This is also one of the current research areas of entangled states.

Let alone the expression in some dark science fiction novels, it is almost "the designed underlying logic can prove that human beings are locked up guinea pigs" and so on.

Real science should not be to reprocess it into even more terrifying rumors to scare people when they discover the unknown.

Instead, after discovering the unknown, try to decipher its mysteries as much as possible.

Of course.

At present, Xu Yun doesn't need to think about such complicated things. Right now, his pressure mainly comes from the cognitive conflicts among the members:

"Hey, students, be safe and don't be impatient."

"I can understand everyone's feelings. After all, what I said is indeed contrary to everyone's existing concepts."

"But it doesn't matter, we still have the same sentence as before - we can put aside the experimental results first, and simply discuss the particularity of the experimental equipment."

Then he looked around and spread his hands down the stage, with a hint of temptation in his tone:

"Don't you want to know how to emit photons alone?"

As soon as the words are exported.

The originally noisy discussion in the audience turned into silence again.

Prepare single photons.

These five short words can arouse the interest of many people in 2022, let alone natural science lovers in 1851.

So soon.

The doubts that were clearly visible on everyone's faces were gradually replaced by hesitation and curiosity.

See this situation.

Xu Yun suddenly felt certain:

Well, the fish is hooked.

well known.

There are many ways to prepare single photons in later generations.

For example, use an ordinary light source to emit light, and then add a strong attenuation to attenuate the light intensity to below the flying tile.

In this way, only a few thousand photons are emitted per second, which is basically a single photon emission.

Another example is the use of a single quantum dot light source.

This thing contains only one light-emitting molecule or structure, which can only emit one photon at a time.

Quantum communication, which is mentioned every day, usually uses this kind of light source.

If the above conditions are still difficult to obtain, students can take out the magic light stick and become Tiga to prepare photons.

However, Xu Yun was not prepared to use these methods. He was planning to conduct an early telecom fraud in 1850:

Electrons are used instead of photons.

After all, the emission of a single electron is easier-at least easier than a single photon, and the accuracy is also higher.

At the same time, electrons or all microscopic particles have wave-particle duality, and even this concept has now been extended to microorganisms:

In 2019, the scientific community has allowed gramicidin with a molecular weight of 1886 to undergo double-slit interference without compromising its biological activity. (doi.org/10.1038/s41467-020-15280-2Focus to learn more)

Again.

Many front-end scientific achievements have surpassed the cognition of ordinary people, which will really give you the illusion of doubting the world.

Therefore, only a small operation is needed, and Xu Yun can successfully replace photons with electrons.

at the same time.

The emotions of many members in the audience were also aroused by Xu Yun's earlier words, only to see the bald boy raised his hand again:

"Student Luo Feng, just now you said that handicraft refers to hand-polishing metal materials, do you need us to do something?"

"bingo!"

Xu Yun snapped his fingers with a happy face, talking to smart people is easy:

"Yes, due to the difficulty of preparation, this experiment also needs about half a year to prepare."

"In the next time, I need everyone to help me do two things."

Then he raised a finger and said:

"The first thing is that in about a week, we will distribute a nonlinear optical crystal and a carving knife to everyone."

"Each of you should draw slits with a spacing of 1 millimeter on the crystal according to your requirements."

"Before the experiment finally starts, I will check your 'homework'. Those with the highest accuracy will have the opportunity to observe the results of the experiment first, plus a special small gift."

It is different from Thomas Young's Young's double-slit interference.

The 'double slit' used in electronic double-slit interference is not actually a piece of paper or plastic.

But nonlinear optical crystals. (When measuring the speed of light, no one found this foreshadowing, disappointed)

Later generations of double-slit crystals are generally made by photoetching technology, which can be accurate to the nanometer level.

However, the early double-slit crystal preparation technology was not mature enough, so it could only be done by hand, just like a single dog without a girlfriend.

This polished crystal is called a crystal grating, and it is one of the few devices that has been used from the invention stage to later generations.

Transmission electron microscope. That is, TEM has a function of electron diffraction spectrum, which can determine the crystal structure, and is often used in double-slit interference experiments of electrons.

According to Xu Yun's understanding, the cost of a nonlinear optical crystal is about 0.5 pounds these years.

Everyone at the scene gave ten chances, and the total was only a little over 150 pounds. An ATM girl said that there was no pressure.

Looking at the club members who were gradually getting excited because they had the opportunity to participate, Xu Yun tapped on the table lightly and reminded:

"Everyone be quiet, the task is not over yet."

After the scene silences.

Then Xu Yun raised a second finger, this time speaking in a more solemn tone:

"Because the precision of artificially polished crystals is not high, we need to add some equipment to achieve the effect of the correction coefficient."

"So in addition to polishing the crystals, everyone has another task to complete."

"In the coming time, each member needs to complete the manual processing and polishing of carbon blocks, tungsten wires, and aluminum tubes on a regular basis. The specific schematic diagrams will be distributed to everyone at that time."

Then the corner of his mouth raised a slight arc, revealing a bright smile:

"If we want to do it this time, let's just do it with a big guy, and never stop!"

half an hour later.

The party broke up.

Lao Tang still had some matters to deal with at the Student Union, so Xu Yun took Avelyn and Mai Mai and left first.

After leaving the activity room.

The silhouettes of the three of them were drawn very long by the street lamps, and the winter air was also tinged with coolness.

After walking for a while, Xu Yun turned and looked at Aveline, and said:

"By the way, classmate Avelyn, I want to trouble you with something."

"What's the matter, tell me."

Xu Yun nodded, took out a small note from his body, and handed it to her:

"I would like to trouble you to find a steel factory with qualified technology. It is best to be an instrument factory to produce these things."

Avelyn took the note, glanced up and down, and read softly:

"Beryllium tubes. Hollow solenoids containing zinc-doped ferrite. Conical bodies of pure molybdenum"

well known.

The discoverer of the element beryllium was Vaukland, who first discovered the element beryllium from beryl in 1798.

In 1828, Vauquelin obtained metal beryllium by reducing beryllium oxide and beryllium chloride with calcium and potassium, respectively.

The preparation process of zinc-doped ferrite appeared in 1813, and now it has become a common solid waste-based magnetic pole material.

Molybdenum was obtained in 1782 by closed burning of a mixture of charcoal and molybdenum acid adjusted with linseed oil in Elm, Sweden.

Therefore, these materials given by Xu Yun are in line with the cognition of the chemical industry in 1850, but they are relatively rare.

I saw Avelyn's eyes quickly swept over these names, and after reading it, she folded it and put it in her pocket:

"No problem, leave it to me, I will write tonight to let the factory open the furnace."

"That's good, wait!"

Xu Yun subconsciously nodded a few times, but soon found that something seemed wrong:

"Student Avelyn, you said to write to the factory to open the furnace. Could it be that you have an instrument factory?"

"Huh? What's so weird about that?"

Avelyn raised her eyelids and glanced at him, and said as a matter of course:

"Newton's ancestor studied optics very deeply at the beginning. At that time, the equipment produced by many instrument workshops did not meet his requirements, so he opened an instrument workshop by himself."

"After more than a hundred years, this workshop has developed into one of the best instrument manufacturers in Europe."

"And I am the sole heir of Newton's ancestors, so this factory naturally belongs to me now."

"In addition, don't worry, I treat those workers very well. If you don't believe me, you can go to London to inquire about it."

"."

Xu Yun opened his mouth, making a gesture to speak out, but in the end he didn't speak.

Then he suddenly thought of something, and quickly looked around.

After confirming that there was no one there, she said to Avelyn:

"Student Aveline, how much assets do you have under your name now?"

"Assets?"

Avelyn stopped and counted with her fingers:

"The annual dividend of tomato sauce is about more than one million pounds, and then there is an instrument manufacturing factory, a steel factory, two shipyards, four carriages and horses, and a farm of more than 1,000 acres."

"Prince Albert asked me before if I wanted to be a part of the Firearms Bureau. I don't like war so much, so I refused."

"If the dividend deposit and the business are all converted into cash, it will be about 70 to 80 million pounds?"

Xu Yun and Mai Mai:

"??!!"

Convex (艹盘艺), why did you find out the identity of this rich woman at this time?

The 70 to 80 million in these years will be tens of billions in future generations.

No wonder the girl turned a blind eye to her IOU at the beginning, and she really didn't pay attention to the hundreds of thousands of pounds

And at the same time Xu Yun's heart was shaking, Avelyn's question rang in his ears again:

"Luo Feng, it's not difficult to produce these devices, but what are you going to use them for?"

Only then did Xu Yun come back to his senses, and took a look at the rich woman.

After a moment of silence, two words popped out of his mouth:

"Secret!"