A world out of nothing

Blackbody radiation, photoelectric effect, atomic spectra, de Broglie waves, quantum entanglement, strong and weak interactions, theory of everything ...... What exactly are these daunting concepts talking about? What are gluons, bosons, photons, Higgs particles, neutrinos ...... and what are these "sons"? Mendeleev, Curie, Roentgen, Einstein, Planck, Schrödinger, Fermi, Feynman, Born, Heisenberg, Pauli, Bohr, Landau, Dirac, von Neumann, Compton, Oppenheimer, Yang Zhenning, Li Zhengdao, Wu Jianxiong, Ding Zhaozhong, Stephen Hawking ...... Why do these familiar or unfamiliar names remain in history? This is a chronicle of the microscopic world, from Mendeleev's periodic table of elements to Witten's superstring theory, telling the development of quantum mechanics from nothing to something. It is a collective biography of quantum mechanics scientists, documenting those who have advanced the knowledge of the microscopic world. The geniuses who emerged one by one and passed away one by one, bringing us infinite emotions as they gathered and dispersed. This is a history of scientific exploration spanning a century, from World War I to World War II, from the discovery of X-rays to the subjugation of nuclear energy, the scientists of quantum mechanics have advanced the development of medicine, influenced the course of war, and changed the fate of mankind.

01.The birth of the chemical table of elements

On February 2, 1907, it was a bitterly cold day in St. Petersburg, with the temperature dropping to more than -20 degrees Celsius. A group of students walked through the dripping streets to hold a funeral for their teacher. The crowd of up to 10,000 spectators and accompanying people, the lineup is very "luxurious". Those who have listened to the traditional comedy "White Party" may know that in the old days of China's rich people's funerals, the lineup was also very luxurious. The front of the procession is often the eldest son of the deceased, holding the remains of the deceased; followed by friends and relatives; and then the back is a variety of chanting and practice of the procession, monks, old Taoist several people, etc.. The drummers also work very hard, and the sound of the suona is especially individualistic, as the so-called "trumpet sound swallows", creating a continuous atmosphere of sadness. But Europeans are not so lively, the atmosphere is solemn and solemn, everyone just quietly walk to the cemetery. The large banner held by the students at the front was neither the name of the deceased nor a photo of the deceased, but a series of symbols that read H, Fe, Zn ......

What kind of person's death can cause such a big show? And what are those strange symbols? Now as long as you have studied secondary school chemistry know that those symbols are chemical element symbols, H is hydrogen, Fe is iron, Zn is zinc ...... can be out of the funeral how also with chemistry on the side of it? Because the one who just died is the great Russian chemist Mendeleev - the discoverer of the periodic table of elements (Figure 1-1)!

Mendeleev was born in 1834 in cold Siberia, where his father was the principal of a high school, but unfortunately his father died when Mendeleev was 13 years old. Mendeleev's mother was very strong and raised a group of children alone. Mendeleev had 17 siblings, enough to start a basketball league. Mendeleev was the fourteenth in the family, so we might as well call him "Master XIV". Mendeleev's studies were badly skewed, and Latin in particular gave him a headache, often failing exams. What should he do if he could not pass the exams and graduate? Fortunately, the school teacher was a relative of his, so he barely passed and graduated. After graduation, Mendeleev, like a bird out of a cage, dragged a few classmates who also did not like Latin up a nearby hill and burned their Latin textbooks to the ground. Where there are exams, where there is burning textbooks, history always repeats itself in a different way over and over again.

Figure 1-1 Statue: Mendeleev and the Periodic Table of Elements

Mendeleev's mother was no exception. In ancient times, Mencius' mother moved three times, and Mendeleev's mother was no better. When her husband died, the family's income was reduced drastically, and her mother's glass factory was closed down due to a fire, which made life even worse. In 1894, she decided to sell her family's assets and go to Moscow, 2,000 kilometers away, where the educational resources of the big cities were more abundant; later she moved to Berlin, Paris, and finally to St. Petersburg, the capital of Russia. Mendeleev was also a good student and went to medical school, which was a promising career for doctors and lawyers at that time. Unfortunately, Mendeleev fainted during his autopsy class and had to drop out. When his father's alumnus, the director of the St. Petersburg Higher Pedagogical School, heard about this, he decided to help Mendeleev. The teacher training college did not charge tuition fees, and Mendeleev's family was in financial difficulties, so it was the perfect place for him to study. In exchange, it made sense that after graduation the student would have to work as a teacher in a designated school.

In 1850, Mendeleev was enrolled in the physics and mathematics department of the teacher training college, where he excelled. In September of the same year, Mendeleev's mother died of an illness, and Mendeleev was determined to study even harder, winning a gold medal at the school and graduating with the first prize in 1855. Unfortunately, at the time of graduation he got tuberculosis and spent a long time in bed. While recuperating in the Crimea, he completed his master's degree. After graduation, he worked as a teacher in many high schools, such as Simferopol and Odessa, all in that part of Ukraine. He taught a wide range of subjects, and he also had to do research and write papers. Mendeleev's family was a glass maker, and he had been working with silicates since he was a child, so his papers were also related to silicates, for example, "Structure of Silicate Compounds".

In 1857, Mendeleev was hired as a chemistry lecturer at the University of St. Petersburg, but his salary was so meager that he had to work as a tutor to support his family. Not only him, but also his predecessor, Professor Zinin, had to work part-time as a tutor to subsidize his family when he first entered the workplace. There was an engineer from Sweden to help the tsar develop mines, the engineer's child also followed to Russia, Qi Ning gave the child as a tutor. The boy was really smart and very good at chemistry in his teens. His name is Alfred Nobel, is the future of the Nobel Prize, the establishment of the famous explosives king. Alfred Nobel's father engaged in mine development, so his achievements in the explosives industry is considered to have a family history. Theoretically, Nobel and Mendeleev is considered the same master brother relationship, are Zinin's students. Another famous person among Zinin's students is Borodin, a chemist whose achievements in his profession are not as famous as his achievements in his hobby, he was a member of the "Powerful Five" of the Russian musical school, wrote the symphonic poem "On the Steppes of Central Asia" and the opera "Prince Igor". Professor Zinin also recommended them, as talent is hard to come by.

Between 1859 and 1861, Mendeleev was selected to study in Germany and France. After traveling abroad, Mendeleev's greatest feeling was that Russia was too backward, and many advanced instruments were not available in Russia, even test tubes and flasks and other appliances needed to be made by himself. Luckily, his family was from a glass factory, so it did not take much effort to make a flask or a test tube. So when he met the famous chemist Benson in Western Europe, the two of them chatted particularly well, because Benson was also good at making his own experimental instruments. That era is the era of the chemical industry from scratch, the chemical industry progresses very fast, chemists are particularly easy to become industrialists, such as Nobel, his family is doing industry, a cannon sounded gold, the famous weapons company Bofors is his family opened. Invented the alkali method of Solvay later also made a fortune. These two people will be mentioned later.

Mendeleev didn't think much about it at that time, he just wanted to give good lessons to the students at school. He taught basic inorganic chemistry at the university. As soon as he started his chemistry class, he studied various chemical elements. In 1863, scientists had already discovered 56 chemical elements, and on average, a new one was discovered every year. At that time, the discovery of new elements was the work of chemists, who could not have anticipated that physicists would take their jobs a few years later. With so many elements, what is the connection between them? In 1829, the German chemist Debellena proposed the idea of "three elemental groups", dividing 15 of the 44 known elements into five groups. The chemical properties of the elements seemed to exhibit a periodic pattern. The Frenchman Deschamps-Cotes proposed a "spiral diagram" of the properties of the elements, and the German Mayer published a "table of six elements". Later, Newlands of England proposed that the chemical properties of the elements are periodic, and that every seven elements will have similar chemical properties, called the "octave". He made a presentation at the Royal Society of England. After listening to the report, everyone was happy and said: "You are so "funny", you think the elements are the same as the scale, do re mi fa so la ti? That's nonsense! Now you know how to order them by atomic weight, why don't you order them by the Latin alphabet? Newlands was devastated. At that time, the scientific community did not think that these elements were intrinsically related to each other, and that the chemical similarities were just a coincidence. Anyone who studied the periodic law of the elements at that time was cynically ridiculed to varying degrees.

Mendeleev was also studying intensely the connections and laws between elements, but people around him, including his teacher Professor Zinin, did not support him. In their opinion, the chemical elements were not connected to each other. Mendeleev grew up playing cards, and he made many cards, on each of which he wrote the names of the elements, their atomic weights, the chemical formulae of the compounds and their main properties. Afterwards, he arranged the cards systematically, first by dividing them into three groups and arranging them by the atomic weight of the elements, but to no avail. He disrupted this combination by arranging them into rows, and then arranging the elements with similar properties in each row into columns. ...... Mendeleev was excited by the fact that this arrangement led to a situation that he had not expected at all - the properties of the elements in each row changed gradually from top to bottom according to the increase in atomic weight. For example, the properties of zinc are similar to those of magnesium, so these two elements are arranged in two adjacent rows, with zinc next to magnesium. According to the atomic weight, in the same line next to zinc should be arsenic, if the arsenic directly behind the zinc, arsenic will fall into the line of aluminum. However, these two elements are not similar in nature. If we put arsenic further down the list, it will be adjacent to silicon. But the nature of silicon is different from the nature of arsenic. Thus, arsenic can be further down the list, behind phosphorus. There is a pattern to the arrangement of the elements! But how can this be explained by the fact that there are still two empty spaces between zinc and arsenic? Mendeleev excitedly imagined that these empty spaces might belong to elements that had not yet been discovered and whose properties should be very similar to those of aluminum and silicon! He went one step further than Newlands and discovered that the more than 60 known elements were not arranged consecutively; there were several empty compartments in between, and there should be undiscovered elements that could fill in these compartments.

Mendeleev found the pattern in the simple arrangement of the symbols of the chemical elements, and he put aside all other work to concentrate on the arrangement of the elements, which he found to be imperfect in the table.

He brought various academic journals related to it, read and studied them repeatedly, and found that the materials in the journals about the properties and composition of certain compounds often contradicted each other. He believed that this was the result of inaccurate determination of atomic weights, which also made some elements in his elemental table not ranked in accordance with their properties.

Mendeleev decided to conduct experiments himself, and in 1862, during an expedition to the Baku oil fields, he proceeded to remeasure the atomic weights of some elements. After six months of work, he found that some of them did not match the conclusions of others. He ranked them in the ranks of elements with similar properties according to the atomic weights of the elements he had determined.

In March 1869, Mendeleev first proposed the periodic law of the elements in a paper entitled "The Relation of Elemental Properties to Atomic Weight", and thus the world's first periodic table of elements was born!

Mendeleev's periodic table of elements (Figure 1-2) has 67 compartments and 4 empty ones. Mendeleev predicted and described in detail the properties of three elements - "boron-like", "aluminum-like" and "silicon-like" - which were unknown to science at that time. But the peers from all over the world shook their heads in disbelief and unanimously accused the periodic table of elements of being pure formalism, a classification of elements based on their proximity for the sake of research, which was actually useless.

Figure 1-2 1871 version of the periodic table of elements

One day, six years later, Mendeleev was reading the Journal of the French Academy of Sciences when he came across an article about the discovery of a new element called gallium by Lecoq de Boisbordelain. He couldn't wait to read it. The properties of the newly discovered element were similar to those of the "aluminum-like" element predicted by Mendeleev. No doubt, this was a great victory! However, the French scientist Lecocq determined the specific gravity of gallium to be 4.7, while Mendeleev calculated it to be 5.9. Mendeleev wrote to Lecocq and told him that the properties of gallium he had discovered were the "aluminum-like" properties he had predicted six years earlier, and told Lecocq that the specific gravity of gallium he had determined was incorrect.

After reading Mendeleev's letter, Le Coq was confused. Mendeleev did not get this element at all, so how could he conclude that the specific gravity he had determined was incorrect? Still, it was easy to test the specific gravity, so Le Kock took the measurements again carefully, and he was convinced that Mendeleev was right! It was only after reading Mendeleev's paper on the periodic law published six years earlier that Le Coq fully understood the significance of his discovery: he had experimentally proved the prediction of the Russian scientist Mendeleev, thus confirming the correctness of Mendeleev's periodic table of elements! The discovery of gallium caused an even stronger reaction among scientists, and Mendeleev and LeCock immediately became famous all over the world. Encouraged by this initial triumph, scientists began to explore the other two elements that Mendeleev had predicted had not yet been discovered. Dozens of laboratories in Europe were working intensely, and thousands of scientists were eager to make unusual discoveries.

Another four years later, Swedish scientist Professor Nielsen discovered a new element that perfectly matched Mendeleev's description of "boron-like", which Nielsen called "scandium". In early 1886, the German chemist Winkler discovered the new element "germanium", which again confirmed Mendeleev's prediction of a "silicon-like" element.

After the periodic law of the elements was recognized, all kinds of honors came to Mendeleev, and he became the world's first-class master of chemistry and the hero of science in the hearts of the Russian people overnight (Figure 1-3). He was appointed as a foreign member of several national academies of science, and in 1882 he was awarded the highest honor of the Royal Society, the David Medal, together with Meyer. Despite his great contributions, Mendeleev did not become a member of the Russian Academy of Sciences because he supported the student movement in St. Petersburg and resigned from the University of St. Petersburg in anger, offending the Tsarist government. After Zinin's death, the Academy of Sciences was vacated, and the education department pressured the committee not to allow Mendeleev to be elected, and the final vote was 9:10 in favor. But Mendeleev did not care, he simply refused to join. Later, the government asked him to be the director of the "General Directorate of Weights and Measures", and Mendeleev introduced the international system of units into Russia. The navy asked him to help improve gunpowder, as they had just lost the battle at Lushunkou in 1905. Mendeleev worked everywhere for Russia.

Figure 1-3 Mendeleev commemorative stamps

Mendeleev also did not get the Nobel Prize because the jury had a scientist who had a personal grudge against Mendeleev, a man named Arrhenius, who proposed the doctrine of ionization of solutions. Because of his ionization theory, he failed to pass his graduation thesis and could not graduate. His supervisor thought that he was talking nonsense, but internationally known academic leaders looked up to this student who could not graduate and even came to see him at school, which scared his supervisor a lot. After coming to power, he learned to take personal revenge on others. It is his interference, resulting in a vote for 4:5 against, Mendeleev did not get the Nobel Prize. In the end, where there are people, there are rivers and lakes, this year's Nobel Prize was awarded to Moisan. After the turn of the year, we think that this time it should be Mendeleev's turn to get the prize, which know Mendeleev suddenly died. Mendeleev said, "Genius is like this: if you work all your life, you become a genius." He really worked until the last moment, and due to a sudden heart attack, Mendeleev died on February 2, 1907 (January 20, 1907 in Russian).

Mendeleev simply discovered the periodic law of the elements. As the atomic weight increases, the properties of the elements are approximated at intervals. But what is the law behind the periodic law of the elements? People do not know. Where would nature easily reveal its secrets to humans? Wouldn't that be too cheap for us.

Just when everyone was marveling at the magic of Mendeleev's periodic table of elements, there was trouble. William Cavendish, the then Chancellor of Cambridge University in England, was the rightful Duke of Devonshire. His family ancestors have a "science geek" named Henry Cavendish, this person is eccentric, and not married, deep in the study of science, a lifetime of indifference to fame and fortune, never rely on the number of brush papers to reflect their academic level, leaving a wealth of manuscripts. His successor, William Cavendish, 7th Duke of Devonshire, became the Chancellor of Cambridge University and built a laboratory out of his own pocket, employing Maxwell, the master of electromagnetism at the time, to take the helm, a position equivalent to the head of the physics department of Cambridge University. Maxwell was interested in Cavendish's manuscripts and spent a lot of time organizing them, and after Maxwell's death in 1879, Baron Riley (née John Strutt, the third Baron Riley) took over.

Baron Riley noticed one thing recorded inside Cavendish's manuscript. A glass container, upside down inside the lye, air are gathered at the top. Stick in two electrodes, hit the electric spark, the oxygen and nitrogen in the air under the action of the spark will form nitrogen dioxide. Nitrogen dioxide is acidic and will be absorbed by the lye solution. There will also be a small amount of carbon dioxide in the air, which itself is also acidic and will also be absorbed by the lye. With the continuous discharge, the top air less and less, it is reasonable to say that there is nothing else in the air, and finally should be absorbed little left, all the air will be consumed. But Cavendish found that this is not the case, and finally there is always a small bubble can not be eliminated. Why is this? Cavendish just made a record, and did not draw a conclusion. 100 years have passed, we simply did not pay attention to this matter, but Baron Riley noticed. He was measuring the density of various gases, other gas density measurement results are very accurate, but only the density of nitrogen is always measured inaccurate. (Figure 1-4)

Figure 1-4 Cavendish used a similar device in principle

There are two ways to obtain pure nitrogen, the first is to extract nitrogen from nitrogen-containing compounds, and the second is to remove other gases from the air, and then only nitrogen remains. With these two methods to obtain the nitrogen gas measured density is actually different, a difference of 1.2 per thousand. Baron Riley a head two big, this is why in the end? This if others happen to be, simply do not take it seriously, but Baron Riley is a particularly careful person, he always felt that this thing is not right. The devil is always in the details, many scientific discoveries are in the decimal point after several digits of the value of the change dug out. He repeated the test over and over again, and the measured specific gravity just wasn't right. So Cavendish's manuscript gave him an inspiration, could there be other components in the air?

Baron Riley himself can not handle, they will send out a wide range of heroes to see who is interested in helping him. After shouting for half a day, no one paid any attention to him. Then a man named Ramsay popped up and expressed his interest (Figure 1-5). This Ramsey used a different approach. He let the air constantly through the blazing hot magnesium powder, magnesium powder is very lively, high temperature will interact with oxygen and nitrogen. Finally, the tossing and turning, always leaving a small bubble. This small bubble in the end what is the thing? The amount is too small, the determination of the composition is obviously not enough, Ramsey began to burn magnesium powder on a large scale, the final collection of this strange gas several liters, Baron Riley himself also made another 500 ml. This is good, enough for experiments. They tried to find ways to put this stuff together with other elements, heating and also, discharge, people are swords and guns, and who do not react. This is what is sacred, actually have a vajra invincible body? Ramsey took a look, can not toss this thing, then had to bring out his teacher's most handy magic weapon.

Figure 1-5 Baron Riley and Ramsay

Who is Ramsey's teacher? His teacher was Kirchhoff, a physicist of great renown. More importantly, Kirchhoff also had a "good friend" (Kirchhoff's friend, referred to as "friend"), which is the aforementioned Benson. This Benson is good at their own drumming chemical instruments, the lack of a bottle or jar, they can build. The laboratory commonly use alcohol lamps, but the temperature of the alcohol lamp is not enough, this student began to use gas to make high-temperature lamps. But the gas lamps made by Benson were so dense and smoky that they did not work well. It so happened that his student brought back from England a new lamp designed by Faraday, but this lamp had a small flame and low temperature, still not enough. Benson came up with an improvement plan, and finally Peter Disdega was able to improve the lamp according to Benson's ideas, but the name was still "Benson lamp" (Figure 1-6).

Figure 1-6 Bunsen burner

Bunsen burner is actually a gas lamp, the temperature is very high, can reach 2300 degrees Celsius, and the gas lamp flame color is very light, will not interfere with the experiment. Kirchhoff and Benson worked together at the University of Heidelberg, and at that time Benson was fascinated by the phenomenon that different metallic salts sprinkled on the Bunsen burner would appear in colorful flames, which were very beautiful. Benson discovered that the colors seemed to be related to the metal elements. For example, if you burn a salt containing sodium, the light will be yellow, and if you burn a salt containing calcium, the light will be brick red. The more Benson burned, the more excited he was, and what he caught burned. Kirchhoff could not stand it anymore: Stop burning! You burn up endlessly!

Benson told Kirchhoff that the different colors are likely to represent different elements. Kirchhoff's eyes lit up: Really? It seems to be so ah, Kirchhoff's brain turned, people with subjective impressions to describe the color, is not at all reliable, to accurately describe the color of light, can only rely on spectral analysis. He said to Benson, Benson a thigh, said dry. Kirchhoff immediately went to find a trigonometric prism, two people a knocking, built the world's first spectrometer (Figure 1-7).

Figure 1-7 Spectrometer

Figure 1-8 Spectral lines of low pressure sodium lamp

They both burned again, the metal salt that can be burned to find and burn again, a great success. The spectrum of the sodium salt, for example, is two yellow spectral lines, not a continuous spectrum, and the spectral lines are very narrow. The spectral lines of various elements are not quite the same (Figure 1-8). If the continuous spectrum is not easy to identify, now a thin spectral line, that is like a unique bar code for each element. Benson also sprinkled a large amount of metal salt on it to test whether Kirchhoff could invert the elements based on the spectral lines. After many successive tests, Kirchhoff always answered without fail. The two men were so happy that they both discovered a new method of identifying elements with high sensitivity, which was in 1859. The following year, the Yuanmingyuan was burned. I can not help but feel a little, are people, the gap is so big ......

It was on October 20, 1859 that they both made a presentation to the Berlin Academy of Sciences. The title of the report was so scary that they said they had figured out the composition of the elements on the sun. A group of scientists at the bottom of the stage wondered, "When did you two go for a walk on the sun? When the two of them described the experiment in detail, everyone couldn't help but applaud. Newton used a prism to discover the dispersion of light, the original sunlight can be broken down into different colors. Later, the German physicist Furlong and Fay invented the grating, which can also decompose the spectrum, and the effect is better than the trigonometry. He found that the spectrum of sunlight has a large number of dark lines, and he recorded as many as 600 of them. But people never knew where these dark lines came from and why they were there. Benson and Kirchhoff found that these dark lines corresponded to the bright line spectra emitted by certain elements. In this way, the two of them determined that the Fron and Fe lines (Figure 1-9) are the fingerprints of the chemical elements inside the Sun.

Figure 1-9 Furlong and Feline

Kirchhoff said they burned everything they could and found everything they could. The more than 600 spectral lines of the sun correspond to the elements on Earth one by one. In other words, the composition of the celestial bodies inside the universe should be roughly the same. Astrophysics has thus entered a new phase. Humans can now use spectra to analyze the elements that make up matter.

Turn back to Baron Riley and Ramsay. They really have no choice, the newly discovered gas is invulnerable to guns, no matter how you toss, it does not react with other elements. Ramsey remembered his teacher Kirchhoff's spectrometer. But his teacher had always burned metal salts to determine the spectrum, how to do the gas? It was impossible to burn it on a flame. This is not difficult to defeat the scientists, they invented a way to discharge in the gas bottle, using the electric field to excite the gas glow. The person who invented this thing called Crooks, he is one of the backup group of Baron Riley and Ramsay, this device is called "Crooks tube". Of course, they did not expect this discharge of the tube actually led to the birth of two other major discoveries. A mouth can not say two things, let's put aside.

With the help of the discharge device it is possible to observe the spectral lines of the gas. Not to see, a look at the shock ah, Ramsay found that the spectrum of this element has never seen before, it is clearly a new element. The gas was so inactive that they gave it the name "argon", which means laziness in Greek, and the inert gas got its name. When the British Science Association met in Oxford, they announced to the world from the rostrum of Oxford University that there was a gas in the air that they did not know existed before. Everyone was dumbfounded. I did not expect that the ordinary air inside there are unknown secrets. At this point, some people thought about it! No, according to the periodic table of elements, this element does not belong to any of the spaces. The periodic table does not foresee the existence of this thing at all. Is the periodic table wrong?

Ramsey himself is calm, the newly discovered argon element is not like the element of which clan, it is difficult to be self-contained? This is quite possible. Ramsey later picked up where he left off and isolated several more noble gases. These gases formed a new group of the periodic table, adding another column to the periodic table, which illustrates the foresight and foresight of Mendeleev's periodic table. This was already in 1895, when Mendeleev was unavailable, being the director of the General Directorate of Weights and Measures. The Tsar did not like him, but he was so famous that he had to be replaced in an unoccupied position to save nonsense.

In the late 19th century, many disciplines were blossoming. Everyone was confident that there was nothing they couldn't handle if they just kept digging. But it didn't last long, and a few years later, the 20th century changed, and if the 19th century science was characterized by being "reliable" and "fixable," then in the 20th century, the scientific community was ruined several times. The 20th century physics is characterized by "unclear, unclear, just under the frown and on the heart".

Take Kirchhoff, for example, whose main work is still in physics. He introduced the concept of black-body radiation. The so-called black body, that is the ideal object that does not reflect any radiation. In this case, any radiation you can measure is emitted by this guy himself. But such an ideal object in nature generally does not exist, but reality can simulate an ideal black body. Suppose a container with a rough interior and a small eye on the wall, if there is light shot in, in the rough surface inside is constantly reflected and absorbed, the probability of just being able to come out of this small eye is very, very low. This small eye, basically, can be treated as a black body to.

Kirchhoff came up with this idea in 1862. This is the result of three years since he began to "burn things" in 1859, summed up. The black body will radiate its own energy, will also absorb energy, only with the temperature has nothing to do with the composition of matter, he deduced from Maxwell's electromagnetism theory. But he did not expect that this inadvertently dug a big hole for classical physics. Now people have unknowingly dug two holes: one is where the periodicity of the elements actually comes from; the other is what is the cause of the spectral lines, why the spectrum is not continuous? Do all the spectral lines of an element conform to some mathematical law? Kirchhoff just dug a hole anyway and died in 1887. As luck would have it, someone else fell into this hole later. One was the aforementioned Baron Riley, one of the discoverers of inert gases. Another was a mathematics teacher, whose name was Balmoral, also involved in the affair.

For Balmain, this is a mathematical problem, not a physics problem. It's just a matter of finding out the mathematical relationship between a bunch of numbers, and that's easy to do. After two tosses, he was really tossed out. Balmain was already 60 years old at that time, and the old man was really not ambiguous. His formula was so accurate that it differed from the actual measured value by only 1/40,000, and the formula was written in an elegant and simple way. Later on, the old man got addicted to the formula, and he also developed the spectra of helium and the spectral lines of lithium (Figure 1-10).

Figure 1-10 The four spectral lines of the Barr's end line system in the visible range

Balmain senior played an important role in the development of spectroscopy and modern physics. The mystery behind the spectral lines was not at all simple, and a late-bloomer gave a very beautiful explanation and won the Nobel Prize in Physics for it. But this was already decades later.

In the eyes of scientists, the spectral line formula is so beautifully simple. The public, however, is baffled by them and most people have no interest in them. However, the publication of a photo aroused strong public interest in physics and became a hot topic of discussion on the streets.