1900: A physics genius wandering around Europe

Chapter 598: Quantum entanglement principle and verification! Wonderful experiment! Bruce inequality! Shocking the audience!

The concept of quantum entanglement shocked all the bigwigs present.

This "ghostly action at a distance" is simply incredible.

It’s as if the two entangled particles have a magical “telepathy” that transcends time and space and senses each other.

When physics has developed to the point of quantum entanglement, it is not far from metaphysics.

Einstein looked excited. He could not accept the existence of quantum entanglement.

There are indeed some superluminal phenomena in this world.

For example, in the Big Bang theory, the expansion speed of space is faster than the speed of light.

Or you can take a flashlight and randomly point it at the sky. The speed of the light emitted by the flashlight is also superluminal.

This velocity is generally called the "phase velocity".

Light itself cannot exceed the speed of light, but what can be exceeded is the speed of change of the phase state of light.

Even human thoughts can reach any corner of the universe in an instant.

All of the above are superluminal phenomena.

But if you analyze it carefully, you will find that these superluminal phenomena have one characteristic in common, which is that they have nothing to do with matter.

They are either related to space, or to abstract states, or to inexplicable consciousness.

Quantum entanglement is completely different. It is a real interaction between matter.

Matter is completely locked to the speed of light and it is absolutely impossible for it to have any properties faster than the speed of light.

So, even if quantum entanglement does not transmit information, Einstein could not imagine that it could exceed the speed of light.

How could two particles infinitely far apart interact with each other instantaneously?

If so, what is the mechanism behind it?
So Einstein asked in shock:

"Bruce, I don't agree with your theory of quantum entanglement."

“What kind of physical mechanism can support this kind of interaction beyond space?”

Li Qiwei smiled slightly and said:

"Quantum entanglement, like the principle of the constancy of the speed of light, is one of the underlying rules of the universe."

"At least we can't understand it for now and can only passively accept it."

Wow!
Everyone was shocked!
If quantum entanglement is the underlying principle, then there is really no way to explain it.

There are many such examples in the field of physics.

After all, natural science is similar to philosophy and both require some [default assumptions].

For example, the concept of space, the concept of time, the concept of matter and so on.

It is impossible for physicists to explain these premises using more fundamental concepts.

However, whether quantum entanglement is such a premise is also a matter of discussion.

So, Li Qiwei continued:

"Of course, I can also provide several feasible perspectives to help everyone understand quantum entanglement more deeply."

Wow!
Everyone immediately pricked up their ears and looked excited.

Who knows what will happen next may be related to several Nobel Prizes.

Professor Bruce's predictions have never disappointed anyone.

"The first is that quantum entanglement may not be an interaction, but something structural."

"There is a deeper and more fundamental structure to our universe than just space."

"This change in structure leads to the existence of quantum entanglement."

"Second, quantum entanglement is some kind of inherent property of the microscopic quantum world."

"It is just like spin, an objective form of quantum existence and has nothing to do with the universe itself."

"The third is that quantum entanglement is the projection of the higher-dimensional world into the three-dimensional universe, so it can ignore space."

"It's like a two-dimensional creature that can't figure out what the height of a three-dimensional creature is."

“Perhaps quantum entanglement is the projection of objects in four-dimensional or five-dimensional space.”

"But the universe we live in is three-dimensional, so we will never know the truth about quantum entanglement."

hiss!
Everyone was shocked when they heard this!

The three guesses proposed by Professor Bruce are more fantastic than the other, almost like science fiction concepts.

But everyone actually felt that there was a slight possibility.

“Quantum entanglement is too mysterious.”

“If we can understand the mystery of quantum entanglement, we should be not far from the ultimate truth.”

At this time, Rutherford, who had been silent for a long time, suddenly spoke:

"Bruce, how do you verify the correctness of quantum entanglement?"

“Quantum entanglement can exceed the speed of light, but humans and even any experimental equipment cannot exceed the speed of light.”

“Therefore, the infinite action at a distance of quantum entanglement can never be confirmed in experiments.”

"How can we evaluate a theory that is destined to be unproven?"

Wow!
Everyone woke up instantly.

Rutherford hit the nail on the head.

Any theory must be verified by experiments!

Even quantum mechanics is no exception.

Even the bizarre probability waves, uncertainty principle, and complementarity principle have been verified by experiments.

Therefore, even though Einstein strongly opposed it, most people still support quantum mechanics.

But now, here comes the problem.

Professor Einstein's thought experiment cannot be verified experimentally.

Professor Bruce's theory of quantum entanglement cannot be verified experimentally either.

The argument between the two men lost its meaning.

"No, strictly speaking, it is Professor Bruce who is at a disadvantage."

"Because a perfect theory should be able to explain any doubts."

“Even if the questioning cannot be realized, the theory should be able to disprove it based on logic and experimental results.”

Everyone was talking about it.

It would be a pity if such a wonderful discussion did not have a definite result in the end.

This is a loss even to the physics community.

Einstein looked solemn.

What Rutherford said was actually what he just wanted to say.

He really couldn't imagine the existence of quantum entanglement unless he saw it with his own eyes.

At this moment, Li Qiwei smiled faintly and said:

"There is really no way to verify that quantum entanglement works over infinite distances."

"We can't really separate a pair of entangled particles by a light-year."

"However, quantum entanglement itself can be verified."

"And I just happened to think of a plan."

hiss!
Everyone was shocked when they heard this!
"My God!"

"Professor Bruce not only proposed quantum entanglement, but also came up with a verification plan?"

"Isn't this the same as the single-electron double-slit interference experiment a few days ago?"

"It's too strong!"

Rutherford and Einstein's eyes simultaneously gleamed with brilliance and they were extremely shocked.

Bruce can actually prove quantum entanglement!

Is this really possible?

Li Qiwei said:
“The core of the argument between Professor Einstein and me was not the superluminal mechanism of quantum entanglement, but determinism and uncertainty.”

"Professor Einstein believed that the states of the two particles were determined before observation."

"And I think the state of two particles can only be determined when they are observed."

"So, I only need to prove that the state of a particle cannot be determined before observation, and I can prove that Professor Einstein is wrong." "Then, I will use experiments to prove that observing the state of one particle can affect another particle."

“Take the electron, for example.”

"For two electrons, even if they are only a few kilometers apart, the Coulomb force between them is small enough to be negligible."

"In other words, if you can prove that two electrons that are a few kilometers apart are somehow related to each other."

"Then it is sufficient to show that this correlation is quantum entanglement."

"Otherwise, there is no known interaction that could explain this phenomenon."

When everyone heard this, their eyes suddenly lit up.

There is absolutely nothing wrong with Professor Bruce's logic.

"It is impossible for two electrons to collude like humans, and there is no involvement of photons in this process."

"So, if one particle can really affect another particle, then this influence must transcend time and space."

"The infinite-at-a-distance nature of quantum entanglement is a natural inference."

"At least if this experiment succeeds, it will prove that quantum mechanics is not a problem."

But the question is, how to conduct this experiment?

Rutherford, the world's top experimental physicist, couldn't figure it out for the time being.

At this moment, everyone's eyes were once again focused on Li Qiwei, their faces full of anticipation.

Li Qiwei explained as he drew the picture:

“As shown in the picture.”

"The electron spin we just discussed only has two directions: up and down."

"If we analyze the electron in a three-dimensional coordinate system, we can see that the electron spin is only on the z-axis (up and down) at this time."

"But the electron's spin projection can also be measured on the x-axis (front-to-back) and the y-axis (left-to-right)."

"For example, if measured on the y-axis, the electron's spin direction is still up or down. (Calculated based on the projection)"

“Now, a concept is artificially defined.”

"When the spin of electron A is upward and the spin of electron B is always downward, the spin correlation between A and B is defined as +1."

"When the spin of electron A is upward, and the spin of electron B is always upward, the spin correlation between A and B is defined as -1."

“When the spin of electron A is upward and the probability of electron B being downward is 50%, the spin correlation between A and B is stipulated to be 0.”

"If we always measure the spin of two electrons on the same axis, then the correlation must be +1."

"In this case, it is impossible to tell whether the two electrons are quantum entangled or not."

"So, think about it another way, measuring the spin of electron A on the x-axis and the spin of electron B on the y-axis, and see how they are correlated."

"This correlation is denoted by Pxy, and the angle between x and y is 0° to 180°."

"The same goes for Pxz and Pzy."

"Here comes the point!"

"If Professor Einstein is right, the spin directions of the two electrons were determined before they separated."

"And there is no correlation between the two electrons."

"Then the spin correlation is always +1 when measured only on the x-axis."

"At this point, slowly move the electron detector in the y direction so that it forms a certain angle with the detector in the x direction."

"At this point, the spin correlation will gradually decrease."

"When the angle is 90°, the spin correlation becomes 0; when the angle is 180°, the spin correlation becomes -1."

"By repeating this experiment a large number of times, we can statistically draw a correlation between the two electrons."

"If Professor Einstein is right, then this correlation must be linear."

"Similarly, if we measure Pxz and Pzy in the same way, we will get the same result as Pxy."

"As shown in the figure, based on the above experimental logic and mathematical deduction, we can eventually derive a correlation inequality."

"That is: |Pxz﹣Pzy|≤1+Pxy."

"If this inequality holds true, it means that Professor Einstein is correct."

"If this inequality does not hold, it means quantum entanglement is correct."

“The above is the experimental plan I designed.”

quiet!
Deathly silence!

Everyone was stunned after hearing this!
The innovation of this experiment exceeded everyone's imagination.

For a moment, no one could fully understand.

Everyone's mind is filled with constant whispers: Who am I? What is this?
"Oh my God! How on earth did Professor Bruce come up with this verification scheme?"

"And in such a short time, it's incredible."

"If anyone says that Professor Bruce is not good at experimental physics again, I will give him a big dick."

"One inequality can decide the most pressing controversy in quantum mechanics!"

"It's absolutely terrifying!"

"I think this inequality will be called Bruce's inequality in the future."

After more than ten minutes, the silence in the room was finally broken and bursts of exclamations broke out.

Everyone was discussing intensely.

Bruce's inequality name was also called out, and everyone felt it was natural.

This inequality is so important that it even determines the life and death of quantum mechanics!

But only a few people really understood this experiment.

Rutherford was shocked and said excitedly:
"There is nothing wrong with the logic of the experiment."

"It can verify the correctness of quantum entanglement."

"What a genius idea! This experimental plan is truly amazing!"

The experimental physics giant Rutherford has spoken, which is enough to prove that Professor Bruce's plan is correct.

Soon, after explanations from Bohr and others, everyone understood.

Everyone looked excited:

"Is the winner finally coming?"

At this time, Lorenz suddenly smiled and said:

"Everyone, please look out the window."

"I'm afraid we won't be able to complete Professor Bruce's experiment today."

"Also, are you sure you want to do this experiment tomorrow?"

Wow!
As soon as the words fell, everyone couldn't help but yelled:
"Do it, you must do it!"

“We want to witness this great moment with our own eyes!”

“I don’t want to go back and only read about this experiment that changed the world of physics in a paper.”

"Professor Bruce, do it!"

At this moment, even Einstein, Rutherford, Bohr and others were moved.

Like everyone else, they can't wait and don't want to miss this historic moment!

Li Qiwei smiled slightly.

"As you wish."

Then, he discussed with several bigwigs.

In order to save time, all experimental equipment had to be temporarily borrowed from several universities in Brussels.

Everyone believes that the Belgian side will not find it troublesome, but will do its best to meet all the needs of Professor Bruce.

Just as Li Qiwei and others were discussing the details of tomorrow's experiment.

The physics community is already in an uproar.

"what happened?"

"Isn't the three-day meeting over?"

"Why haven't the bosses come out yet?"

"In the end what happened?"

(End of this chapter)