The clouds are rolling and the three-month calculation and thesis writing time have passed in a flash.

On that day, under the sunshine of Southern California, the computational papers mentioned by Gu Play and his wife, as well as the subsequent writing of popular science monographs, had been preliminarily completed.

In July, all the papers were submitted and defended.

In the following month or so, Gu Wan concentrated all his time to write the popular science monograph, and also captured his tool man sister Li Shuangye, who had just finished her junior year at the Central University of Science and Technology in China, and took advantage of the summer vacation to come to the United States.

Every day, he provides his sister with good food, drink and fun, in exchange for her helping Gu Yu work and write books.

Li Shuangye is also painful and happy, after all, the hedonistic conditions provided by his brother are very good, almost every day under the maid's service to reach out for food to open his mouth, and when he is tired, he can also make an appointment to take him out for a ride, or find a masseuse at home to help with massage.

Is the source of the pain, naturally there are too many manuscripts, and the black hole-themed science fiction that my brother arranged for her to write last time has not been completely written, and she is going to do a popular science monograph again.

However, it is better to have a boss who wants the horses to run and give the horses grazing fiercely, than those who don't give graze, Li Shuangye was originally interested in this career, so he was willing to eat it.

"Brother, sister-in-law, take a look at this version of the manuscript, does this meet your requirements?"

One day at the end of July, after Li Shuangye sprinted for a day of writing in his brother's big villa with a sea view, in the middle of the night, he finally threw the complete manuscript on Gu Wan's desk.

Gu Yu glanced at it a few times, and then threw it to Ma Yiyi, who was sitting opposite, but his face was facing Li Shuangye and ordered: "Let your sister-in-law see it, it's useless for me to see it, if a layman like her can find it understandable and interesting, then it can be a blockbuster and can have the effect of attracting real readers." ”

Hawking's "A Brief History of Time" on Earth seems to have sold millions of copies, but I have to admit that at least seventy or eighty percent of the people who buy books don't read that book at all, and they buy books to pretend to be forced.

In particular, a large number of social science liberal arts students with swollen faces and fat people are placed on the desk, showing that they have bought such high-quality books, or bought them and sent them to share them with friends, and then such a difficult academic work on physics was thrown there to eat ashes, and they didn't read it at all.

Anyone who really regards the sales of "A Brief History of Time" as the actual readership of the book, and thus thinks that popular science is also a profitable business, is a big mistake and will suffer.

Ma Yiyi faced her husband's lack of face, and she was also slightly petty: "You have to be a layman who can understand it, then it's not enough to find me, my sister can be regarded as a scholar."

You should find a maid in the house, then it can be really simple and easy to understand. People Bai Juyi writes poems and pursues the old woman's understanding, why don't you keep up with Bai Juyi?"

Gu Play knew that he had said the wrong thing, so he comforted his wife with a little body language and told his wife to stop.

Ma Yiyi struggled a few times, and finally got angry enough and obediently began to read the manuscript.

“…… According to the observations of cosmologists, the proportion of chemical elements in our universe today is about 73% of the total number of atoms in the universe with hydrogen, about 23% with helium, and all the heavier elements such as lithium, beryllium, boron, carbon, nitrogen, and oxygen add up to only 4%~5%.

This elemental composition is what our universe is today. Allowing stars to converge and begin continuous, gentle nuclear fusion and radiate energy, allowing terrestrial planets to form and orbit stars, and eventually to evolve into life.

We can't help but ask, why is this proportion? Is this a coincidence or an inevitability? If we were to do it all over again, would it still be this proportion? Would it still form the world we have today? Is there any sufficiency of the prerequisites for the birth of life?"

The introduction is quite alarmist, and elementary school students can understand it, at least knowing what the book is about and what the current situation is.

Ma Yiyi felt that this part was fine, so she continued to look at the professional part.

"The ratio of hydrogen to helium in the universe, and even the ratio of other elements heavier than helium, lies in the ratio of protons to neutrons in the universe.

As we all know, a standard helium nucleus is made up of two protons and two neutrons, while a standard hydrogen atom is made up of one proton and no neutrons. Helium atoms need 1 to 1 neutrons and protons, and hydrogen atoms only need protons.

As for the elements heavier than helium, they could not have existed at the beginning of the universe, because they were all produced after the birth of stars as a result of ultra-high-pressure nuclear fusion reactions. When the universe was first born, there was only radiation, only high heat and expansion, and gravity and pressure were secondary, so it was not yet the turn of nuclear fusion to enter the universe.

The birth of the first star is far away from the birth of the universe, and it is the product of the universe that has cooled down enough, so it is not within the scope of discussion of the creation of the universe.

So, the core of the question goes back to the most succinct formulation: At the beginning of the creation of the universe, why was the ratio of the total mass of hydrogen and helium close to 3 to 1, and why was the ratio of protons to neutrons close to 7 to 1 at that moment?"

Reading this, Ma Yiyi did a little mental calculation and confirmed that the numbers were fine.

(Hydrogen is pure protons, so 3 parts hydrogen has 3 parts.) Helium is a proton neutron in half, so the mass of 1 part helium can be broken down into 0.5 parts mass and 0.5 parts medium. Therefore, when hydrogen and helium are added, the proton neutron is 3.5 parts to 0.5 parts, which is 7 to 1. ）

This starts with the law of life and death of the middle son. As we all know, neutrons are extremely unstable when they are not fixed to the nucleus of an atom and exist in a naturally free state, automatically releasing an electron, and then its body decays into a proton.

Moreover, this process is not reversible in its natural state, that is, the uncharged neutron will decay into a positively charged proton, and a negatively charged electron. However, positively charged protons and negatively charged electrons cannot be re-synthesized into neutrons - this is what is often referred to as β decay in atomic physics.

However, the above-mentioned decay in the natural state is irreversible, but it does not mean that the beginning of the universe is also irreversible - 0.1 seconds after the birth of the universe, the temperature of the universe at that time was as high as 100 billion degrees, in that environment, the electrons will be too large because of the huge energy, and the state of 'strong electrons', this strong electron can be reintegrated with the proton when it hits the proton and becomes a neutron.

So, if the universe has been kept at 100 billion degrees Celsius, then the ratio of protons to neutrons there should always be five to five, instead of the current seven to one. The reason why the follow-up is irreversible is that the universe has cooled rapidly, unable to maintain a high temperature of 100 billion degrees or at least tens of billions of degrees, and after only a dozen seconds, the temperature has dropped to billions of degrees, and the natural reverse decay of neutrons resynthesized by the above-mentioned strong electrons and protons can no longer occur.

At this point, the question shifts further: how many neutrons will survive from the time the neutrons begin to 'die' in batches due to β decay and transform into protons, and before the temperature of the universe is reduced enough to produce stable nuclei?"

Ma Yiyi read this, and the outline of the first part of the book was roughly finished.

It's grandiose, and the second part is full of rigorous calculations.

In the book, Gu Yu calculated the temperature required for protons and neutrons to form the nucleus of helium - in the previous 100 billion to billions of degrees, the nucleus did not exist. Because it is too hot, the movement of elementary particles is too violent, and the nucleus cannot exist at all, because it cannot be restrained, and will be broken free by protons and neutrons.

For the nucleus to exist, the upper temperature required is 900 million degrees.

That is, more than 900 million degrees, all atoms will collapse, and none of them can exist in the atomic state, but only in the state of elementary particles such as discrete protons, neutrons, and electrons.

The core of the follow-up content is also deduced from "how long it took to go from the temperature of the universe to the point where it was not enough to support the reverse process of beta decay, and to the further cooling to 900 million degrees." And during this time, how many neutrons are finished".

The average period of beta decay is 15 minutes. In other words, if the interval between the time points when the universe cools to these two temperatures is more than 15 minutes, then all the neutrons in the universe will be killed, or only a negligible very few will survive.

Today's world will be a world of pure protons, pure hydrogen atoms, and nothing else.

But fortunately, the interval between the time points when the universe cools down to the above two temperatures is not as long as 15 minutes, so some of the neutrons in this world have survived, and there are all the elements behind the periodic table, instead of just a single element.

Galaxies, planets, and civilizations should all be grateful for the grace of the universe that cools down fast enough.

The calculation process in the book is very cumbersome, and in the end, Gu Yu preliminarily calculated a time of about 3 minutes and 28 seconds, and determined that the universe was reduced to 900 million degrees at about 3 minutes and 28 seconds after its birth.

It was at this point that a quarter of the neutrons survived, and three-quarters of the neutrons decayed into protons, so everything in the universe followed.

The time of 3 minutes and 28 seconds has never been written on the earth, but there is a great earth scientist at Weinberg who has calculated a number of 3 minutes and 46 seconds.

(Weinberg is also a Nobel laureate in physics, and on Earth, he won the Nobel Prize a year later than Penzias and others, who discovered the cosmic microwave background radiation.) Because his calculation of the cooling rate of the origin of the universe needs to rely on the observation of the cosmic microwave background radiation. Therefore, Gu Wan also chose to further do the follow-up inversion calculation after observing the latest and lowest cosmic microwave background radiation. ）

If Gu Wan's book had been written here, then he would not be any better than Weinberg on Earth. But the problem is that he writes much more than that.

His conclusion differs from Weinberg's because he adds other radiative perturbation variables. Gu Play not only calculated the inversion of the cosmic microwave background radiation, but also added the inversion of other latest achievements such as antimatter and black hole radiation error.

Of course, that's not all. In fact, there are many more distractions that cannot be explained clearly in tens of thousands of words.

In a word, except for the "dark energy" error proposed by the earthlings who needed to use the Hubble Space Telescope to observe the major error in the observation of the cosmic expansion rate, it cannot be calculated by Gu Yu into the perturbation variables.

Other interference variables that can be summarized without relying on ultra-advanced experimental instruments, observation equipment, and purely theoretical brain supplements are all included in Gu Play.

And the process is very clear, basically adding a variable and recalculating it again, so that people can feel the aesthetics of physics.

As for "dark matter and dark energy", he can only make prophetic mentions for the time being, such as "If the future discovery of the expansion rate of the universe is wrong with the current calculation of our cognitive quantities, then all the above calculations will have to be reversed, and we must be ready to accept new discoveries at any time and define those unknown physical quantities in time".

At this point, his new popular science monograph has been extremely solid, and even more holes have been buried to prove it.

Waiting for the world to prove his greatness,

Or that year, he opened his own space company and spent $2 billion to build an orbital space telescope, similar to the Hubble of the earthlings.

Then he can prove his greatness on his own.

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