Shulou(Shulou.com)11/24 Report--

This article comes from the official account of Wechat: ID:fanpu2019, by Wang Shanqin

Oppenheimer, the father of the atomic bomb, is a controversial celebrity. The film Oppenheimer has made him one of the hotspots of world public opinion again after 56 years of illness. Because of his complex experience and character, most people ignore his important contribution in the field of physics. This paper introduces several representative and important achievements of Oppenheimer in order to give people a better understanding of his contributions to physics and astronomy.

Write an article | Wang Shanqin

J Robert Oppenheimer (J. Robert Oppenheimer,1904-1967) is a controversial celebrity. He gained great fame for leading a group of scientists and engineers to build the world's first atomic bomb and successfully explode it (the Manhattan Project). He was suppressed by the military and the government for opposing the manufacture of a hydrogen bomb by the United States after World War II, and was censored and became a tragic figure because of his previous close ties to the left.

A photo of Oppenheimer's ID card while leading the Manhattan project, whose ID number is K6. Photo: Los Alamos National Laboratory has close contacts and cooperation with many of his scientific colleagues, but has been morally criticized for meddling in the marriages of at least two collaborators. Some people think he is a genius, some people think that he puts on airs, and some people think that he is a playboy who likes to hook up with women.

Oppenheimer's complex character and experience make most people ignore his identity as a physicist and therefore his important contributions to physics and astronomy. This paper introduces several representative and important achievements of Oppenheimer in order to give people a better understanding of his contributions to physics and astronomy.

Early learning experience on April 22, 1904, Oppenheimer was born into a Jewish family in New York City. His mother, Ella Oppenheimer (Ella Oppenheimer,1869-1931), was a painter; his father was a wealthy textile importer Julius Seligman Oppenheimer (Julius Seligmann Oppenheimer,1871-1937).

Oppenheimer's father and mother. Photo Source: public copyright 1921, graduated from Oppenheimer High School, but took a year off because of colitis. In 1922, Oppenheimer entered Harvard University, majoring in chemistry. In 1925, he graduated with honors from Harvard University with a bachelor's degree.

Oppenheimer's talent may be partly hereditary. Although his father has not been to college, he is very capable. His brother, Frank Oppenheimer (Frank Oppenheimer,1912-1985), later became a physicist, studying nuclear physics and working on uranium enrichment in the Manhattan Project.

In 1924, Oppenheimer was admitted to Cambridge University. He originally wanted to follow Rutherford (Ernest Rutherford,1871-1937), a famous master of experimental physics, but his college mentor already said in his letter of recommendation that he was strong in theory and weak in experiment. Rutherford read this "reverse letter of recommendation" and was naturally not interested in him. However, he still went to Cambridge University after graduating from Harvard University.

Perhaps after some haggling, Rutherford's mentor Thomson (Joseph John Thomson,1856-1940) asked him on condition that Oppenheimer complete a basic experimental course. This request almost sent Oppenheimer away. He suffered from poor experimental skills and homesickness, and his relationship with the course's mentor, Patrick Blackett,1897-1974, deteriorated sharply.

On one occasion, Oppenheimer put venomous apples on Brackett's table and tried to poison the latter. Luckily Brackett didn't eat.

In the movie Oppenheimer, the remorseful Oppenheimer rushed into the laboratory and happened to see Niels Bohr,1885-1962, who was visiting the lab, picking up a poisoned apple to eat. Oppenheimer grabbed it and threw it into the dustbin, saying that the apple had been eaten by worms. This plot should be fictional, because such a coincidental plot can only be found in films and novels.

In fact, Oppenheimer almost went to jail for trying to poison his mentor. Oppenheimer's parents asked Cambridge University not to file criminal charges or deport him. Oppenheimer was given a suspended sentence and had to meet regularly with psychiatrists in London for psychotherapy. If he had really snatched the poisonous apple and threw it away, no one would have known about it, and he would not have almost gone to jail.

Brackett dodged a bullet and won the 1948 Nobel Prize in Physics for his achievements in experimental physics.

Molecular continuum spectroscopy, molecular dynamics and chemical bonds in 1926, Oppenheimer, who suffered a year in the laboratory at Cambridge University, went to the University of Gottingen, then one of the centers of world physics, to study under quantum mechanics master born (Max Born,1882-1970). The year before, Heisenberg (Werner Heisenberg,1901-1976) established the matrix form of quantum mechanics, and quantum mechanics was born; born and Jordan (Pascual Jordan,1902-1980) and Heisenberg soon perfected this epoch-making work in the same year.

Oppenheimer had a good time at the University of Gottingen. In 1926, Oppenheimer completed the quantum theory of molecular continuum. He obtained a method to calculate the electron transition probability, and used it to calculate the photoelectric effect of hydrogen and X-ray, and obtained the absorption coefficient of K edge. His calculations are consistent with the observation of the X-ray absorption of the sun, but not with the X-ray absorption of helium in the laboratory. Years later, it was proved that the sun was composed mainly of hydrogen, and his calculation was correct.

In March 1927, 23-year-old Oppenheimer received his doctorate through his doctoral thesis defense. It was less than two years after he graduated from college and only one year after he began to study for a doctorate.

The chairman of the defense committee is Frank (James Franck,1882-1964), who is famous for conducting the Frank-Hertz experiment with Hertz (Gustav Hertz,1887-1975), which proves Bohr's theory of energy levels of hydrogen atoms. They were awarded the Nobel Prize in Physics in 1925. Hertz here is the son of the younger brother of Hertz (Heinrich Hertz,1857-1894) who verified the electromagnetic wave theory.

After the defense, Frank said, "I'm glad it's over." he's asking me questions. " Under normal circumstances, the respondent committee asks the students questions to examine the students' real ability. )

In 1927, Oppenheimer and born jointly published an important paper on molecular dynamics. This paper was received by the magazine in August of that year, so it was submitted after he graduated from his doctorate. But Oppenheimer should have collaborated with born on the research before graduating from his PhD. In this paper, the motion of the nucleus in the molecule is separated from the motion of the electron, and the motion of the nucleus is ignored, so that the dynamic properties of the molecule can be calculated by quantum mechanics. This approximation method is called born-Oppenheimer approximation (Born-Oppenheimer approximation), which is one of the important foundations of quantum chemistry and molecular physics.

In the movie Oppenheimer, when Oppenheimer and Heisenberg first met, the latter praised the former for their molecular work, referring to the born-Oppenheimer approximation. Although Heisenberg was only three years older than Oppenheimer, he became one of the leading figures in the field of physics because of his previous creation of quantum mechanics. By contrast, Oppenheimer was a junior at the time. It is reasonable for Heisenberg to praise Oppenheimer as an academic elder.

During his stay in Europe, Oppenheimer published more than a dozen papers. With these high-quality papers, he easily won the National Research Council Award (United States National Research Council Fellowship) from the California Institute of Technology (California Institute of Technology,Caltech) in September 1927.

During his stay in Caltech, Oppenheimer established a close friendship with Linus Pauling (Linus Pauling,1901-1994). They collaborated to study the nature of chemical bonds, Oppenheimer did mathematical calculations, and Pauling explained the results. However, their friendship ended quickly when Oppenheimer dated Pauling's wife. Pauling won the Nobel Prize in Chemistry in 1954 and the Peace Prize in 1962, becoming one of the winners of the double Nobel Prize.

In the autumn of 1928, Oppenheimer visited the University of Leiden (University of Leiden) in the Netherlands and gave a lecture in his new Dutch language. During this period, he got the nickname Opje, which was later translated into English Oppie by his students. In the movie Oppenheimer, friends call "Oppie" and students chant "Oppie,Oppie,Oppie." That's where it comes from.

After the return of positron theory, Oppenheimer was hired as an associate professor in the physics department of the University of California, University of California, Berkeley,UCB, and took a part-time job at the invitation of Caltech.

In 1928, Dirac (Paul Dirac,1902-1984) established relativistic quantum mechanics by combining quantum mechanics with relativity. Dirac found that this equation not only leads to a positive energy solution that describes electrons, but also leads to a negative energy solution, which he believes represents protons.

In 1930, Oppenheimer published a paper "Notes on the Theory of the interaction between Field and matter" (Note on the theory of the interaction of field and matter), which challenged Dirac's view. He believes that the mass of the particle corresponding to the negative energy solution should be equal to that of the electron, and the mass of the proton is much larger than that of the electron, so the negative energy solution cannot be a proton; if the negative energy solution is a proton, then the hydrogen atom will quickly self-destruct. The famous mathematical physicist Hermann Weyl (1885-1955) also proposed that the mass of particles corresponding to negative energy solutions should be equal to that of electrons.

Driven by Oppenheimer and Weir, Dirac proposed in 1931 that the negative energy solution represents an undiscovered particle whose mass is equal to the electron mass, and the charge is opposite to the electron charge, that is, it is positively charged. This is the positron. In fact, Oppenheimer's 1930 paper essentially predicted the existence of positrons.

In 1936, Anderson (Carl David Anderson,1905-1991) discovered positrons in cosmic rays, which was the first time that antiparticles had been discovered. Anderson won the 1936 Nobel Prize in physics for this.

Lamb shift and quantum electrodynamics according to the Dirac equation, the two energy levels of the hydrogen atom 2S1/2 and 2P1/2 have the same energy ("degeneracy"). In 1931, Oppenheimer and student Harvey Hall published a paper "Relativistic Theory of photoelectric effect" (Relativistic Theory of the Photoelectric Effect), which pointed out that the two energy levels are actually different. Hall received his doctorate in 1931 and was the first doctoral student to graduate under Oppenheimer.

In 1947, another of Oppenheimer's doctoral students, Lamb (Willis Lamb,1913-2008 Magi received his doctorate under Oppenheimer in 1938) and Retherford (Robert Retherford,1912-1981, Lamb's doctoral student, not Rutherford mentioned above) used microwave technology to measure the energy difference between the two levels, so the difference was called "Lamb shift" (Lamb shift). Lamb won the 1955 Nobel Prize in Physics for measuring Lamb shift.

In the same year when Lamb shift was discovered, Bette (Hans Bethe,1906-2005) explained the mechanism of Lamb shift for the first time, which laid the foundation for the development of quantum electrodynamics (QED). Bette has a deep knowledge of nuclear physics; he pioneered the study of nuclear reactions in stars and became an authority in nuclear astrophysics, for which he won the Nobel Prize in physics in 1967.

Bette also joined the Manhattan Project during World War II as head of the theory group. He played a decisive role in calculating the "critical mass" of the atomic bomb and designing the "implosion method" (implosion method). Bette played a heavy part in the movie Oppenheimer. The fragments that often appear around the core in movies are what implosion requires. After these fragments explode, they produce extremely uniform pressure toward the center, and the intense compression reduces the critical mass of the core of the radioactive material below the mass of the core, thus initiating the chain reaction and successfully exploding. )

Bette. Source: Schwinger (Julian Schwinger,1918-1994), who later became one of the QED aggregators, also intersects with Oppenheimer. After earning his doctorate at the age of 21, he worked as a postdoctoral fellow at UCB from 1939 to 1941 and won the 1965 Nobel Prize in Physics for his contribution to the QED field. During his time at UCB, he may have been influenced by Oppenheimer.

It is said that Oppenheimer likes to sit down and ask questions to test others when his postdoctoral or doctoral students are teaching assistants for themselves. When Schwinger was also his assistant, Oppenheimer remained the same; however, Schwinger quickly helped Oppenheimer kick the habit with his own quick and perfect answer (it is unclear whether Oppenheimer will return to the habit after Schwinger left).

Schwinger is a favorite pupil of the rabbi (Isidor Rabi,1898-1988). The rabbi is a good friend of Oppenheimer and has a heavy role in the movie Oppenheimer.

During the Oppenheimer-Phillips process in UCB, Oppenheimer had a close relationship with Lawrence (Ernest Lawrence,1901-1958), a master of experimental physics. Lawrence also played a heavy role in the movie Oppenheimer.

Lawrence invented the world's first cyclotron and set up a radiation laboratory in UCB. The laboratory later became Lawrence Berkeley National Laboratory (Lawrence Berkeley National Laboratory,LBNL). Oppenheimer provided a theoretical explanation for the experimental data obtained by Lawrence's team.

LBNL's city commuter car. Image: taken in downtown Berkeley in 1935, McMillan (Edwin McMillan,1907-1991), Lawrence and Robert Thornton used a cyclotron to accelerate the deuteron beam and bombard the target nucleus. The deuteron consists of a proton and a neutron. When the deuteron bombards the target nucleus, the protons are relatively far away because of the repulsive force of the protons in the target nucleus, which makes the neutrons point to the target. When the velocity of the deuteron is very high, the neutrons will fuse with the heavier target nucleus and the remaining protons will escape.

McMillan and others found that when the deuteron energy is low or the target nucleus is lighter, the results are in good agreement with the theory of Gamov (George Gamow,1904-1968). When the deuteron energy is higher or the target nucleus is heavier, the ability of nuclear interaction is lower than that predicted by Gamov theory. McMillan was later involved in the Manhattan Project and won the 1951 Nobel Prize in Chemistry for his important contributions to nuclear physics and chemistry. His tutor was Pauling when he was an undergraduate. )

McMillan (left) and Lawrence (right). Source: in ENERGY.GOV1935, Oppenheimer and Phillips, one of his first doctoral students (Melba Phillips,1907-2004, received his doctorate in 1933) published a paper, "notes on the transmutation function of deuterons" (Note on the transmutation function for deuterons), and proposed a theory to explain the results. This theory adopts adiabatic approximation, that is, it is assumed that there is no heat loss in the whole system during the collision. This theory, later known as the Oppenheimer-Phillips process (Oppenheimer-Phillips process), was an important achievement in early nuclear physics and is still in use today.

The ultimate mass of neutron stars in 1936, 32-year-old Oppenheimer became a full professor. Around this time, he became interested in astrophysics.

In 1938, Oppenheimer and his postdoctoral fellow Thurber (Robert Serber,1909-1997) published "on the Stability of Neutron Nuclei in Stars" (On the Stability of Stellar Neutron Cores), which studied the upper limit of the mass of stable neutron cores.

In 1939, Oppenheimer and student Volkoff (George Volkoff,1914-2000) published "on massive Neutron Nuclei" (On Massive Neutron Cores), which further proved that there is a limit to the mass of neutron stars; beyond this limit, neutron stars will not be stable, but will contract unhindered by gravity.

Since this work is based on the work of Tolman (Richard Tolman,1881-1948) in 1934 and 1939, this limit is called the Tolman-Oppenheimer-Volkoff limit (Tolman-Oppenheimer-Volkoff limit), or TOV limit (TOV limit).

Oppenheimer and Volkoff's paper only considers the degenerate pressure between neutrons, so the TOV limit is only 0.7 solar mass. However, the strong force between hot pressing and neutrons is ignored. Later studies took these factors into account, and the TOV limit was between 1.5 and 3 suns.

The equation of state of extremely dense matter is so complex that the exact value of the TOV limit has never been determined; it is now certain that this value can exceed two suns because such heavy neutron stars have been identified in observations. The study of the merging event GW170817 of double neutron stars shows that the TOV limit of neutron stars can exceed 2.17 suns.

Although Oppenheimer was good friends with Tolman and his work was influenced by Tolman's work, he later intervened in Tolman's marriage. He and Tolman's wife, Ruth Tolman (Ruth Tolman,1893-1957), met in 1928 (Ruth married Tolman in 1924) and became friends first and then lovers after World War II. Tolman was one of two mentors during Dr. Pauling's time. It was amazing that he had intervened in the marriage between master and apprentice.

This relationship did not last long because Oppenheimer soon left Caltech to become director of the Princeton Institute for Advanced Studies (Institute for Advanced Study,IAS) in 1947. In 1948, Tolman died of a heart attack, and Oppenheimer and Ruth continued their on-and-off relationship. In the movie Oppenheimer, Oppenheimer refutes the rumor that Tolman died of heartbreak.

Black holes: the continuous contraction of massive celestial bodies at the end of 1915, Einstein established the general theory of relativity. Soon after, Schwarzschild (Karl Schwarzschild,1873-1916) obtained the expression of the metric (the square of the infinitesimal distance) of space-time near a spherically symmetric stationary object, namely the Schwarzschild metric.

The expression of the Schwarzschild metric becomes infinite in two places, one where the radius is zero and the other where the radius is equal to 2GM / c2. The latter is called "Schwarzschild radius", "gravitational radius" or "event horizon" of spherically symmetric static uncharged celestial bodies. The infinity here can be eliminated by using other coordinates. However, infinity at a radius of zero cannot be eliminated, and if matter is condensed to this point, its density is infinity, which is the "singularity". In the language of the later developed space-time geometry, the geodesic breaks at the singularity. )

A schematic diagram of a spherically symmetric static uncharged black hole (Schwarzschild black hole). The red dot in the center of the graph is a singularity (Singularity), where the density is infinite, the boundary is the event horizon (Event Horizon), and the distance from the event horizon to the center is the Schwarzschild radius (Schwarzschild radius). Source: in Sandstorm de1939, Einstein (Albert Einstein,1879-1955) published a paper on massive spherically symmetric stationary Systems (On a Stationary System with Spherical Symmetry Consisting of Many Gravitating Masses), which used general relativity to prove that black holes could not be produced.

In the same year, Oppenheimer and his doctoral student Snyder (Hartland Snyder,1913-1962), based on a recent paper by Oppenheimer and Volkoff, used general relativity to study the contraction of stars whose masses exceed the TOV limit, and published the paper on persistent gravitational contraction (On Continuing Gravitational Contraction) on September 1.

In this paper, Oppenheimer and Snyder proved that stars of sufficient mass will continue to contract under their own gravity and shrink within the Schwarzschild radius when they run out of nuclear fuel.

At and within the Schwarzschild radius, even light cannot escape, so the whole celestial body becomes black. Such celestial bodies were later called "black holes". This paper by Oppenheimer and Snyder actually proposes for the first time that black holes can be formed within the framework of general relativity.

In this paper, Oppenheimer and Snyder also specifically pointed out that in the process of star contraction, the gravitational intensity of its surface is getting stronger and stronger, and the gravitational redshift of starlight is becoming more and more obvious. the starlight detected by distant observers is getting redder and redder, gradually becoming long-wave radiation. The time it takes for the distant observer to see the star shrink to the Schwarzschild radius will become infinite, so the result will never be seen. However, observers falling as the star's surface shrinks ("co-motion observers") will still feel the passage of time (the author's note: the premise is not torn or killed by tidal forces). It only takes a day or so to feel yourself falling to the Schwarzschild radius. These conclusions are not out of date so far.

An imaginary view of astronauts passing through the event horizon of a black hole from the outside in (for a spherically symmetric static uncharged black hole, the event horizon is the Schwarzschild radius). The observer in the distance could not see him reaching the event horizon, but he could see himself approaching the event horizon and penetrating. Source: this paper by Roen Kelly Oppenheimer and Snyder does not mention Einstein's paper a few months ago. They may not have seen Einstein's paper at that time, or they may not find it appropriate or necessary to refute Einstein directly.

Einstein and Oppenheimer, 1950. Photo source: US Govt. The Defense Threat Reduction Agency film Oppenheimer shows the scene in which Oppenheimer and others celebrate the publication of this paper. The film borrows the words of its characters to say that the news that Hitler started the war stole the limelight of the paper. In fact, even without this major event to steal the limelight, this article could not stir up waves in the whole academic circles at that time, because the physics circles at that time were generally studying topics related to quantum mechanics. general relativity was an unpopular research field at that time.

Moreover, the conclusions drawn by Oppenheimer and Snyder's paper were not accepted by scholars studying general relativity at that time. I'm afraid even Oppenheimer himself won't be so happy about it. He hasn't done any more research in this field since.

It was not until decades later that astronomers gradually determined based on observations that black holes did exist in the universe. In 2017, an international team combined several of the world's (temporary) submillimeter wave telescopes into the event Horizon Telescope (Event Horizon Telescope) and photographed the supermassive black hole in the core of galaxy M87, taking the first picture of a human black hole.

The event horizon telescope captured the supermassive black hole at the core of M87 (the black area at the center of the image) and the material around it that emits large amounts of radiation. This image is a pseudo-color image, using different colors to represent submillimeter wave radiation emitted by substances at different temperatures. Photo Source: Event Horizon Telescope descendants of physics history experts generally believe that Oppenheimer's most important contribution in his life is the work of predicting the inevitable formation of black holes. But Oppenheimer himself doesn't think so. he thinks his most important work is on electrons and positrons.

The world owes him a Nobel Prize. Oppenheimer was nominated for the Nobel Prize in physics in 1946, 1951 and 1967, but did not win the prize.

Oppenheimer's only award in the field of scientific research was the Enrico Fermi Award (Enrico Fermi Award) in 1963. The reason for winning the award is his contribution in the field of theoretical physics and his contribution to the manufacture of atomic bombs in key years. Taylor (Edward Teller,1908-2003) nominated him as the winner to mend the rift between the two. Although the award included a political gesture to rehabilitate Oppenheimer to some extent, he deserved the award for his scientific achievements and his contribution to the manufacture of the atomic bomb. In the movie Oppenheimer, the aging Oppenheimer is decorated with a medal, and his best friend rabbi hobbles over to shake his hand. Taylor comes to shake hands, and Oppenheimer shakes hands with him. This is one of the most moving scenes in the film.

Alvarez (Luis Alvarez,1911-1988), winner of the Nobel Prize in Physics in 1968, believes that if Oppenheimer can live to black holes, he may win the Nobel Prize in Physics for his work on neutron stars and black holes.

But he obviously didn't wait until that day. He was addicted to smoking, so he got throat cancer. After unsuccessful radiation and chemotherapy, he died on February 18, 1967 at the age of 62 (before his 63rd birthday).

In Oppenheimer in 1946, cigarettes were still in hand. Photo: Ed Westcott. Government photographer) in 2020, Roger Penrose,1931- won the Nobel Prize in Physics for using rigorous mathematical methods to prove that black holes are bound to form. Oppenheimer and Snyder first proved this point in physics as early as 1939, when Penrose was 8 years old.

Alvarez, who lived only until 1988, believed that Oppenheimer was qualified to win the Nobel Prize for predicting the formation of black holes. Now, compared with Penrose, who won the Nobel Prize for proving that black holes can be formed by mathematical methods, we are more sure that the world does owe Oppenheimer a Nobel Prize in physics.

Is he a good physicist? Oppenheimer's scientific career is not long. It took only about 25 years from the publication of important papers in 1926 to the cessation of publication in 1950.

During those 25 years, his research was often interrupted or interfered with: from 1942 to 1945, he largely interrupted his own research because he led the Manhattan Project; from 1947, he became director of IAS and served as chairman of the General Advisory Board (General Advisory Committee) of the Atomic Energy Commission (atomic energy commission); and he participated in debates on hydrogen bombs in 1949 and 1950. These administrative positions and debates have obviously greatly reduced the time Oppenheimer can spend on research. In fact, when he returned to Caltech in 1945, he found that he could no longer do research, which should be the reason why he was happy to take up management-related positions.

Oppenheimer (right) and General Groves (Leslie Groves Jr.,1896-1970) (left) led the Manhattan Project in 1942. Source: Los Alamos National Laboratory can say that Oppenheimer's last important work was to predict the inevitable formation of black holes in 1939. As a result, he has been active in physics and astrophysics for only about 14 years. Even during these 14 years, it is a pity that he was unable to devote all his attention to physics because of his wide range of interests (the rabbi euphemistically said that "Oppenheimer was too educated in areas outside the tradition of science").

Looking back on his legendary life, he finished his doctorate in only one year, pointed out Dirac's mistakes at the age of 26, and at the age of 35 completed the pioneering work on the extreme mass of neutron stars and the formation of black holes, which established his position in the field of physics.

During his time at UCB, Oppenheimer promoted UCB's theoretical physics to the world-class level with his excellent physics and management skills. (in the movie Oppenheimer, officials at the hearing asked him why he went to Europe to study. UCB's physics is first-class. Oppenheimer replied: yes, I built it. ), and trained many doctoral students, some of whom became famous physicists.

Some people think that Oppenheimer did not find anything worth discovering and did not become a good physicist. This evaluation is not fair. Although his achievements in the field of physics are not as good as those of Einstein, Bohr, Heisenberg and others, he is still an excellent and even outstanding physicist. As mentioned above, his work on black holes is worthy of winning the Nobel Prize in physics, but he just doesn't live long enough.

But even if he lives a hundred years old, he won't wait for the Nobel Prize. When Penrose won the Nobel Prize for a black hole in 2020, if Oppenheimer was still alive, he would be 106 years old. So far, there has not been such a long-lived Nobel laureate. We can only regret to say that the Nobel committee is sometimes too cautious and conservative.

Nevertheless, we should also understand that a scientist's contribution cannot be measured by whether he has won the Nobel Prize or not. If he has done enough work to win the Nobel Prize, it will be enough to show that he is outstanding and will be remembered by future generations.

Therefore, Oppenheimer's important contributions to physics and astronomy should be remembered by future generations.

Postscript: when I was studying y ú in the UCB Department of Astronomy, I learned that he and Oppenheimer both worked in the UCB Physics Department by consulting Schwinger's data. The building of the UCB Physics Department is next to the building of the Astronomy Department. After learning that both Oppenheimer and Schwinger had worked here, I felt a sense of awe when I entered the UCB Physics Department Building. Writing this article today is a belated tribute to Oppenheimer's achievements in physics and astronomy. He is a controversial figure; however, it is indisputable that he has contributed to the understanding of both the micro-world and the universe.

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.