1900: A physics genius wandering around Europe

Chapter 561: The Power of Antimatter! Terrifying Annihilation! Endless Shock! Does the Anti-World Really Exist in the Universe?
What is antimatter?
What happens when it meets real matter?
This is probably the first question everyone has after hearing about antimatter.

At this moment, when Li Qiwei proposed the shocking antimatter theory, someone finally couldn't help but ask a question.

The entire conference hall fell silent in an instant, and everyone was waiting for Professor Bruce's explanation.

No matter what the result is, today's speech will surely cause a sensation in the entire physics community!

At this time, Li Qiwei spoke.

“This question is complex yet simple.”

"It's complicated because we don't even know the properties of antimatter, so how can we study its relationship with matter?"

"It's simple because we can just find antimatter, put it together with normal matter, and do an experiment to find out."

Everyone smiled.

"However, since I have theoretically predicted the existence of antimatter, I can also try to theoretically predict its properties."

"For the sake of convenience, let's take electrons and anti-electrons as an example."

"Everyone, please look at this new wave equation again."

"It is known that electrons and anti-electrons have the same mass and spin, but their charge and magnetic moment are opposite."

"Let's do a thought experiment."

"Suppose now there is a positron and an anti-electron, moving towards each other at the same speed, and then they collide with each other."

"First, according to the law of conservation of charge, the system formed after the impact must be electrically neutral."

"So it's impossible for an electron-positron to form two positrons, or two antielectrons."

"Secondly, according to the law of conservation of mass, the system formed after the collision must have twice the mass of the electron."

"So, it can't be particles like protons and neutrons, because their mass is thousands of times that of electrons."

"Finally, the collision needs to satisfy the law of conservation of energy."

"In this way, I can probably give a few guesses."

"The first is that after the positron and the electron collide, nothing happens, which is equivalent to an elastic collision."

"Although their individual charges still exist, the resulting system is electrically neutral."

"The second is that after the collision between the positron and the anti-electron, a new particle with twice the mass of the electron is formed, and it is also electrically neutral."

Everyone nodded when they heard this.

These two conjectures are still very reasonable.

Tight logic and reasonable guesswork.

In everyone's mind, the three conservation laws definitely have a higher priority than antimatter.

These three laws can be regarded as the foundation of the foundation of physics and are absolutely beyond doubt.

No matter how mysterious antimatter is, it must obey the law of conservation.

"The anti-universe is not a place beyond the law of physics!"

Therefore, the inferences based on them are also logical.

However, while everyone was discussing, Li Qiwei suddenly said:

"However, I personally don't like the above two conjectures very much."

"I have another conjecture that seems a little weird."

Wow!
Everyone was shocked!
Anything that even Professor Bruce finds incredible must be world-shattering!
But, besides these two collision results, are there any other outcomes?
Planck, Einstein, Schrödinger, Heisenberg and others were all concentrating on thinking.

Then, Li Qiwei continued:

"In the first hypothesis, positive charge and negative charge met, but nothing happened, which I think is a bit unreasonable."

"In the second conjecture, charge neutralization is my preferred view, but I don't like to add inexplicable new particles."

"So, the third conjecture I proposed is a combination of conjectures one and two."

"I think that when the positron and the electron meet, they will become two electrically neutral photons!"

boom!
The whole audience was shocked!

Everyone widened their eyes and found it unbelievable!

How did electrons get involved with photons?

The difference between these two particles is too great.

"How is this possible?"

"I feel that Professor Bruce's third conjecture is a bit far-fetched."

“This is really unbelievable!”

"."

Everyone was talking about it.

However, Planck and other bigwigs frowned and thought about the feasibility of it.

Soon, someone couldn't help but ask:
"Professor Bruce, if the positron and the electron meet and become two photons, doesn't that violate the law of conservation of mass?"

"Electrons have mass, while photons have zero mass."

Wow!
Everyone nodded in agreement.

Li Qiwei smiled slightly and said:

"No! The third conjecture does not violate the law of conservation of mass."

"According to the mass-energy equation in the special theory of relativity, when the positron and the anti-electron meet, they can convert all of their mass into energy."

"And this energy is released in the form of photons."

"This is in line with the law of conservation of mass."

"This process looks like when the positive and negative electrons meet, they turn into a ball of light, and then the electron disappears into space, leaving nothing behind."

"So, I call this process [annihilation]."

hiss!
quiet!
Deathly silence!

Everyone was shocked after hearing the concept of annihilation!
this is too scary!

This is too unbelievable!

When positive and negative electrons meet, they turn into light?
In fact, there is nothing special about matter turning into light.

According to the mass-energy equation, mass and energy are two sides of the same coin.

The missing mass becomes energy, which usually takes the form of photons.

This is the case, for example, with the nuclear fusion process inside stars.

But the annihilation process is obviously more shocking.

Li Chengdao was once again shocked by his second brother's prediction.

He actually had the same idea as his father!

"It's incredible!"

Li Chengde smiled slightly, hiding his achievements and fame.

At this time, Li Qiwei added:

"I don't think there are even conditions required for annihilation to occur."

"Whenever the positive and negative electrons meet, they will immediately annihilate and produce photons."

"This is significantly different from the mass-energy conversion conditions in nuclear fusion."

Many marketing accounts will exaggerate:

"Shocking! Antimatter annihilation is more powerful than atomic bombs and hydrogen bombs!"

"One gram of antimatter can destroy the world!"

All these statements are wrong!
Whether it is antimatter annihilation, nuclear fusion or nuclear fission, the principle of energy release is the mass-energy equation.

The advantage of the former over the latter is that the mass-energy conversion efficiency is different!
The efficiency of antimatter annihilation can reach 100%.

In other words, no matter how much antimatter there is, it can be completely converted into energy.

But the nuclear fission atomic bomb is different.

Because of the existence of critical mass, if you want 1g of matter to undergo nuclear fission, you may need 2000g of matter as a basis.

The remaining 1999g of material is all wasted.

Nuclear fusion is the most efficient method of mass-energy conversion currently mastered by humans, with a mass-energy conversion ratio of approximately 0.7%.

That is, for every 1kg of matter that undergoes fusion, only 7g of energy can be released at most.

Although the efficiency is low, you can rely on great force to work miracles.

If you have 1g of antimatter bomb, I will use a few kilograms of matter to make an atomic bomb, and the energy released in the end will be the same.

Therefore, it is nonsense to say that 1g of antimatter can destroy the world.

To annihilate 1g of antimatter, another 1g of matter is needed, so a total of 2g of matter is converted into energy.

According to the mass-energy equation, this energy is roughly equivalent to 4.3 tons of TNT.

The Little Boy dropped by the United States had an equivalent of 2 tons of TNT.

Therefore, the energy produced by the annihilation of 1g of antimatter is a little more than that of 2 little boys.

It's a long way from destroying the world.

However, the advantages of antimatter annihilation are indeed obvious.

You hold a piece of matter the size of an aspirin tablet in your left hand and a piece of antimatter the same size in your right hand.

Then throw it away.

boom!
Destroy a city easily.

This is the power of antimatter!

There is no need for any wires, any calculation of critical mass, or any purification of elements.

Just a single encounter can lead to annihilation and an explosion of world-destroying energy.

But the problem also followed.

Antimatter is too unstable.

It explodes the moment it touches positive matter, so how can you hold it with your hands?

In later generations, it will be extremely difficult to produce and preserve antimatter.

First of all, the manufacturing aspect.

According to estimates, if Europe's largest particle collider is used and operated continuously for a hundred years, it can produce about 0.1μg (one ten-millionth of a gram) of antimatter.

The energy released by the annihilation of this amount of antimatter is roughly the same as that of a cannonball.

But the cost of manufacturing it, even if calculated only based on the electricity costs of the collider, would be more than $1 trillion!

What a terrible and high price to pay!

Even if you sell the entire Earth to aliens, you still can't raise enough money to produce 10g of antimatter.

Moreover, even if it is made, preserving it will be a big problem.

Currently, scientists can produce about a few nanograms of antimatter each year.

These antimatter are confined in a magnetic trap formed by the magnetic field and cannot come into contact with any matter.

This is countless times more harsh than the conditions for artificial controlled nuclear fusion.

The latter may one day achieve a breakthrough in materials science and be able to create materials that can withstand ultra-high temperatures, thus becoming possible to make containers for storing plasma.

But antimatter cannot be used in any container made up of matter atoms.

Therefore, the so-called antimatter spacecraft engine is just a fantasy, and it is impossible to be assembled in the spacecraft in our positive world.

Not only that, the temperature at which antimatter is stored is almost close to absolute zero, in order to reduce the kinetic energy of the antiparticles and maintain their existence time.

Generally speaking, the antimatter produced by scientists is at the subatomic level or a few anti-atoms.

Their storage time is roughly in milliseconds.

The longest-lasting antihydrogen atom ever confined existed for about 20 seconds.

If humans really encounter an antimatter planet in the universe one day, it will be a problem to take it away.

Therefore, based on the above situation, don’t even think about making antimatter bombs for the time being.

That is impossible!

There was a movie in later generations that told the story of terrorists who stole 0.1g of antimatter from a research institute and wanted to make a bomb to blow up a city.

This plot is a bit far-fetched.

Not to mention how much it would cost to produce 0.1g of antimatter, and how to store the bomb. Even if it was made into a bomb, its power would only be one-fifth of that of the little boy.

I'm afraid it's a little short of destroying the city.

At this moment, the many physics giants present were obviously not interested in making antimatter bombs.

They just want to study the mechanism behind it.

At this time, someone asked again:

"Professor Bruce, why must two photons be generated when the positron and electron annihilate each other?"

"Can't we just generate one photon?"

Everyone exclaimed "Huh".

That's a good question.

After hearing this, Li Qiwei thought for a while and said:
"According to the law of conservation of momentum, if only one photon is generated, then the momentum of that photon will be zero."

"This obviously does not conform to the law of conservation of momentum."

"So, two photons must be generated to balance the momentum."

As he spoke, Li Qiwei began to calculate using the formula.

By combining the new wave equation, mass-energy equation, and mechanics, we can calculate the state of the system before and after the collision.

The formula results show that the probability of generating 2 photons is the highest.

Ridgeway added:
"Of course, all this still needs to be verified by experiments!"

At this time, Einstein smiled and asked:

"Bruce, do you think antimatter really exists in our universe?"

"If so, why have we never found any trace of it?"

Everyone's eyes lit up when they heard this.

This question is probably the one that everyone is most concerned about.

Ridgeway joked:

"Professor Einstein is deliberately making things difficult for me."

"If I could find antimatter now, my theory could be included in textbooks."

Everyone smiled knowingly.

"Well, I'll let my thoughts run wild and tell you what I think."

“I think this question needs to be split into two questions.”

"The first is whether there are [microscopic antiparticles] such as anti-electrons and anti-protons in the universe."

"The second is whether there is [macroscopic antimatter] such as anti-planets or even anti-galaxies in the universe."

"I have different views on the existence of these two types of antimatter."

"First, I don't think there is necessarily macroscopic antimatter in the universe."

"According to the mass-energy equation and annihilation theory, matter and antimatter will explode as soon as they meet, generating enormous energy."

"If an antimatter meteorite the size of a house falls to Earth, the energy it generates will be enough to destroy anything on Earth."

"Even blowing the earth to pieces."

"But so far, the fact that we can sit here and discuss the issue of antimatter proves that there are no antimatter meteorites."

"In addition, the moon is exposed to the vacuum of space and is attacked by countless dust fragments every day."

"If there really is macroscopic antimatter, then we should see big explosions on the moon quite often."

"Obviously, astronomers have not discovered and reported this phenomenon."

"This shows that, at least in the solar system, there should be no macroscopic antimatter."

"Of course, some people may question: maybe there are only no antimatter planets in our solar system or the Milky Way, but there are antimatter planets in the depths of the universe."

“That’s out of the question.”

Wow!
Upon hearing this, everyone started a heated discussion.

Everyone thought that Professor Bruce's analysis was very reasonable.

The energy generated by the macroscopic annihilation of matter and antimatter is truly enormous.

Even if there was an explosion on the moon, people on Earth would be able to see a dazzling light.

Moreover, this kind of explosion does not require any high temperature or high pressure conditions and is billions of times simpler than stellar nuclear fusion.

If there really is a lot of antimatter, explosions should be everywhere.

Therefore, according to the normal principle of averages, it makes no sense that there is antimatter somewhere else but not in the solar system.

What's the matter? You Earthlings are special.

In later generations, astronomers used the most advanced telescopes but have not found any traces of macroscopic antimatter.

Scientists can be sure that there is no macroscopic antimatter within at least a thousand light years.

Of course, none of this is conclusive yet.

Perhaps there is another antimatter universe outside the observable universe.

However, that no longer makes sense to humans.

At this time, Li Qiwei continued:

"And the possibility of the existence of microscopic antiparticles is too high."

"On the one hand, even if a single particle annihilates, the energy produced is negligible."

"Take the positron and anti-electron as an example. The energy produced after their annihilation is about 8×10^-14 J."

"This little bit of energy has no effect on the macroscopic world, so we usually cannot feel the existence of antiparticles."

"In addition, since the annihilation of particles and antiparticles can produce photons, then conversely, under certain circumstances, will two photons become a positron-electron pair?"

"I think it's entirely possible!"

"We can see all kinds of photons in our daily lives, so it must take harsh conditions for photons to become positron-electron pairs."

"And in the vast universe, any extreme environment exists."

"So, I think there is a very high probability that microscopic antiparticles exist in the universe."

"Maybe one day when technology is advanced, we humans will be able to create antiparticles ourselves!"

Wow!
Everyone was shocked!

Professor Bruce's ability to deceive and incite is simply too strong.

After his analysis, everyone present felt that antiparticles definitely exist in the universe.

Since positrons and electrons can turn into photons, it doesn't make sense that photons can't turn into positrons and electrons.

“The universe is so huge!”

“It’s like a super laboratory that can provide any environment and conditions.”

“No matter how magical antimatter is, it is not as magical as the universe itself.”

"So, antimatter must exist in the universe!"

At this moment, many physicists present were full of confidence!
Even Einstein and others were impressed by Professor Bruce's confidence.

Looking at everyone's excited expressions, Li Qiwei continued:
"I know that many people in the physics community are currently studying cosmic rays."

"For example, Professor Rutherford's group, Professor Millikan's group, etc."

"I believe that one day in the future, someone may be able to discover the existence of antiparticles from cosmic rays!"

Li Qiwei sighed in his heart. When talking about antimatter, we have to mention the Chinese physicist Zhao Zhongyao.

In real history, when Dirac proposed the concept of anti-electron in 1928, the world was shocked.

However, no one knew at the time that the positron and the electron would annihilate and produce photons.

In 1929, Zhao Zhongyao studied for his doctorate in Millikan's research group. His research topic was the scattering of hard gamma rays.

The so-called hard gamma rays refer to rays with very high energy, so they exhibit strong particle properties and appear very "hard".

Once, when he was doing an experiment, he discovered that hard gamma rays would produce a special kind of radiation when passing through metallic lead.

At that time, Zhao Zhongyao didn't know what this strange radiation was, but he still rigorously published the data and phenomena in the form of a paper.

At this time, Millikan had another doctor under him, Anderson.

He was very interested in Zhao Zhongyao's research, but he didn't know the mechanism of special radiation.

Anderson's own research topic is the study of cosmic rays.

He directed the rays into a cloud chamber with a strong magnetic field and then analyzed what particles were in the rays.

In 1932, Anderson discovered that a path identical to the electron's trajectory appeared in the Wilson cloud chamber, but in the opposite direction.

This means that the particle has the same mass as an electron, but an opposite charge.

Anderson was puzzled at first, but then he suddenly woke up.

"Isn't this the anti-electron?"

Thus, as the first antimatter discovered, the anti-electron was officially introduced!

The sensation it caused can be imagined.

Anderson became famous all of a sudden!

At that time, the theoretical physics community had already proven that when the positron and electron meet, annihilation should occur and photons should be generated.

Anderson suddenly remembered the experiment conducted by Zhao Zhongyao who was in the same group.

He had a bold guess about the mysterious radiation.

In just the second year, he repeated Zhao Zhongyao's experimental results and proved that the radiation was actually the light produced by the annihilation of positron-electron pairs.

It turns out that when hard gamma rays bombard lead, a pair of positrons and electrons are produced, and this pair of positrons and electrons immediately annihilate into two new photons.

The so-called radiation is the photon after annihilation.

The physics community was in an uproar!
This shows that Zhao Zhongyao discovered the anti-electron earlier than Anderson!

But no one associated all these honors with that young Chinese man.

At that time, Chinese science was weak and had no say in the world physics community.

So, just four years later, Anderson won the Nobel Prize in Physics for discovering the anti-electron.

Zhao Zhongyao, on the other hand, remained unknown.

But Rutherford always insisted on Zhao Zhongyao's achievement in discovering anti-electrons.

He even publicly added a comment to the paper written by Zhao Zhongyao:
"This result provides further evidence for the production of electron-positron pairs."

Nobel Prize winner Tsung-Dao Lee once said:
"Teacher Zhao should have been the first Chinese to win the Nobel Prize in Physics."

At this moment, Li Qiwei looked towards the east with a distant gaze.

"Zhongyao, don't worry. With the principal here this time, no one can bury your achievements."

Huaxia, National Southeast University.

Zhao Zhongyao, who just graduated this year, became an assistant professor in the Department of Physics at National Southeast University because of his excellent academic performance.

Suddenly, he sneezed violently.

A colleague next to me asked, "Teacher Zhao, what's wrong with you? Are you sick?"

Zhao Zhongyao waved his hands quickly: "It's okay, it's okay."

However, he was very puzzled.

Not only was he not sick, but it seemed as if an inexplicable energy was injected into his body, and he felt full of energy!
"Heisenberg, Pauli, Dirac, Fermi and others who participated in the second Physics Olympiad are now well-known in the physics community."

"I, Zhao, am not necessarily weaker than them!"

Zhao Zhongyao heard from the grapevine that Professor Li might come back next year.

He is actively preparing to go to Borneo to apply to become Professor Li's doctoral student.

"That's my battlefield!"

“I must work hard!”

As if they had telepathic connection, Li Qiwei smiled slightly.

After everyone was shocked, Einstein suddenly asked another question.

"Bruce, why is there no macroscopic antimatter in the universe?"

Wow!
Everyone was shocked!
What is the problem?
(End of this chapter)