Oppenheimer: Remembering the physics that first made him great

There is a scene in Christopher Nolan’s new film, Oppenheimer, where the eponymous physicist is thronged by his adoring pupils after his paper is published. They have gathered to celebrate the ‘black hole paper’ that J. Robert Oppenheimer wrote with his student Hartland Snyder. “The world will remember the day,” one of his students says.  

The world of physics does indeed remember the paper. While Oppenheimer is remembered in history as the “father of the atomic bomb”, his greatest contribution as a physicist was on the physics of black holes. The work of Oppenheimer and Hartland Snyder helped transform black holes from figments of mathematics to real, physical possibilities – something to be found in the cosmos out there.

Exceptionally versatile

At the time of this work, Oppenheimer was a professor of physics at the University of California, Berkeley. The Manhattan Project and the atomic bomb were still some years in his future. He was unknown to the public but the community of physicists knew him as the man who had established the finest school of theoretical physics outside of Europe.

Before Oppenheimer, it was customary for young American theoretical physicists to go to Europe, which had become the mecca of physics. Oppenheimer had made the pilgrimage himself in his youth and studied with some of the pioneers of quantum theory, such as Max Born and Wolfgang Pauli. After Oppenheimer joined Berkeley, many of the best young American physicists flocked there instead, drawn to his genius.

Oppenheimer and his students worked on a wide range of topics – from cosmic rays to nuclear physics, from quantum electrodynamics to astrophysics. Each student worked on a different topic, and the exceptionally versatile Oppenheimer oversaw it all.

For most physicists, who prefer to dig deep into one or two topics at a time, this would be a nightmare scenario. But Oppenheimer thrived on it.

When he later became the scientific director of the Manhattan Project at Los Alamos, his versatility helped him oversee diverse aspects of building the world’s first nuclear weapons.

From darkness to light

Among his students, Snyder was regarded as the most proficient at hard mathematical problems. He would go on to make important contributions to accelerator physics and noncommutative field theory. Oppenheimer gave him the problem of black hole formation to solve.

In their collaboration, Oppenheimer provided the vision and Snyder fleshed it out. Together, they brought black holes to life.

The possibility of black holes had been discovered shortly after Albert Einstein developed his theory of general relativity, in 1915. According to this theory, matter warps the fabric of spacetime around it. To determine the exact amount of warp, physicists have to solve a set of equations known as Einstein’s equations. The first person to find such a solution to these equations was the German physicist Karl Schwarzschild: he computed the warping outside a perfectly spherical mass.

Schwarzschild’s solution contained a surprise. He found that if you compute the warping near spheres of the same mass but of smaller and smaller radii, the warp keeps increasing. Below a certain critical radius, the neighbouring spacetime would curve into a pocket from which not even light can escape. That is, if a certain amount of mass was packed into a small enough radius, a black hole would exist around it.

Most physicists dismissed the possibility of black holes as mathematical fiction. They pointed to the fact that there was no known way by which matter could be squeezed so tight that a black hole would form.

A remarkably accurate picture

The next step came from the astrophysicist Subrahmanyan Chandrasekhar. His work showed that black holes could be formed when certain stars run out of fuel and collapse under their own weight. But a description of a star imploding and forming a black hole was still missing.

This is where Oppenheimer and Snyder came in. Oppenheimer had already made a foray into the topic of stellar collapse, which convinced him of the inevitability of black holes. Together with his student George Volkoff, he was able to significantly extend Chandrasekhar’s result.  Now, with Snyder, Oppenheimer set out to provide a mathematical description of the birth of a black hole.

The collapse of a star is an enormously complicated process that would have been impossible to fully understand mathematically. But Oppenheimer had a talent for zeroing in on the essential features of a problem. He told Snyder to solve the problem for a perfectly spherical star with no internal forces. Unrealistic though their model was, Oppenheimer and Snyder’s final result was remarkably accurate.

But even with the simplifications, the problem was not easy. Oppenheimer and Snyder had to work out how the contraction of the star would affect the spacetime inside it. (Unbeknownst to them, the problem had been solved a year earlier by an Indian physicist named Bishveshwar Datt).

For all their simplifications, their final result provided a remarkably accurate picture of the birth of a black hole. It showed that a black hole would inevitably form once the star collapsed into its critical radius. It also showed that the star would continue to implode, eventually reaching infinite density, creating a singularity.

Oppenheimer and Snyder’s work also produced a striking demonstration of the relativity of time for different observers. For an observer on an imploding star that was as heavy as our Sun, it would take mere hours to shrink to the size of the critical radius. But for an observer outside, it would take an eternity. They would see the collapse get slower and slower as the star shrank to become smaller and smaller, never quite crossing the critical radius.

The Oppenheimer-Snyder paper should have closed the debate on black holes. Unfortunately, most physicists were not ready to accept the weirdness of black holes yet and argued that the idealisations that Oppenheimer and Snyder had made were too unrealistic. Oppenheimer himself lost all interest in the subject: he would change the topic whenever someone tried to discuss it with him.

It was only after Roger Penrose proved the inevitability of black hole formation that the importance of the Oppenheimer-Snyder paper became recognised. But by then, both the authors were deceased.

Into the black hole

One has to wonder how Oppenheimer’s life and career would have panned out under different circumstances, if he could have continued at Berkeley as the brilliant teacher and physicist that he was. But that was not to be.

Oppenheimer’s and Snyder’s paper was published by the journal Physical Review on September 1, 1939. Two other notable events took place that day. First, Niels Bohr and John Wheeler published a paper that explained nuclear fission and demonstrated the utility of the isotope uranium-235 to produce nuclear chain reactions. Second, Adolf Hitler’s army invaded Poland, starting World War II.

The course of history from that point on was perhaps as inevitable as the collapse of a star into a black hole. Oppenheimer was caught in its relentless pull, never to escape.

Nirmalya Kajuri is an assistant professor of physics in IIT Mandi.

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Review: Nolan’s ‘Oppenheimer’ is a Harrowing Tale of One Man’s Life | FirstShowing.net

Review: Nolan’s ‘Oppenheimer’ is a Harrowing Tale of One Man’s Life

by Manuel São Bento
July 20, 2023

Christopher Nolan is undoubtedly one of the most influential filmmakers of this century. His movies are regularly featured in articles about the best films of each year, of each decade, and even some of the best in the history of cinema. For me personally, he’s a director whose name alone gets me into the theater every time. Nolan brought narrative complexity to blockbusters, transforming them into impactful stories that left viewers profoundly thinking about what they saw and what happened. The writer / director made audiences all around the world look at the theater experience as something more than an excuse to stuff themselves with popcorn. And he does it once again with Oppenheimer, his 12th feature film since Following in 1998.

Nolan’s last two movies, Dunkirk (2017) and Tenet (2020), were criticized – by a minority, admittedly – for being too confusing and difficult to follow. The first for its three distinct storylines occurring in the sky, the sea, and on the ground. The second for the visuals induced by the sci-fi premise of time going backwards. For these viewers, I don’t think Oppenheimer is going to be any simpler or easier to follow. It’s a narrative totally driven by extremely fast, intricate, scientific dialogue – tons of exposition about quantum physics & mechanics – and with rare moments of analogy explanations to help viewers grasp the most basic ideas.

Three heavy hours spent with dozens of characters each with a significant impact on the main plot or in the protagonist’s arc, as well as different timelines, several meetings and interrogations, sections in color and in black-and-white… all at a pace, sometimes, so brisk that any tiny external distraction can suddenly cost the comprehension of motivations, ambitions, location changes, character names and, mainly, awareness of time and space. Oppenheimer really justifies the use of the expression “it’s not for everyone.” That said…

Oppenheimer is, technically, another masterwork that all film lovers should see in the biggest IMAX screen possible. A phenomenal lesson in how to assemble an incredibly immersive blockbuster with less than half the budget of all others. Nolan has always been known for his insistence on practical effects and shooting on film, something that shows tremendously in DP Hoyte van Hoytema’s crystal-clear images and stunning cinematography. From the mesmerizing close-ups to the shifts between color and black-and-white, it’s one of the most visually fascinating biopics I’ve ever had the pleasure of watching.

Nevertheless, the technical standout must go to the sound production. Both the overall sound design and composer Ludwig Göransson’s score transform Oppenheimer into more than just a movie. In the first few seconds, I could feel the ground shaking, my body vibrating, and my heart pounding. It’s such a potent experience and so rarely felt in a theater that I’m afraid sensitive viewers may feel uncomfortable during some of the more…explosive…moments. It was one of the aspects that helped me maintain my focus on the story at hand and the respective character interactions. It’s an extra layer that contributes exceptionally to the tension and suspense of each scene in an already remarkably atmospheric film.

Nolan’s Oppenheimer movie is divided into three acts quite clearly. The first follows scientist J. Robert Oppenheimer’s (Cillian Murphy) early career up until the moment he becomes director of the Los Alamos Laboratory in New Mexico, where the Manhattan Project was orchestrated. During this period, the audience meets many scientists, colleagues and professors, who accompanied the growth of Oppenheimer as a theoretical physicist, as well as the women who were part of his life. Everyone – I repeat, everyone – has an essential impact on his life, whether by helping to set the path that led Oppenheimer to Los Alamos, building the first atomic bomb, or dealing with the traumatic aftermath.

It’s in this first hour, more or less, that Oppenheimer presents exactly the type of movie it will be. A quasi-documentary that doesn’t waste time with irrelevant information or random conversations. Viewers can complain about the lack of interest or entertainment, but all the scenes have a purpose, so the 180-minute runtime is earned even if we feel its weight. The speed with which characters are introduced and with which, almost immediately, Oppenheimer advances in his career through new studies in different locations with other scientists and associates, is admittedly hard to follow initially.

Watching this movie requires a certain adjustment not only with regards to the frantic pace of the scenes themselves but also regarding the fact that a post-bomb narrative is running simultaneously. As we follow Oppenheimer’s scientific career, we also track the various “trials” about the makings of the “Father of the Atomic Bomb” and the people who surrounded him over the years. Contrary to what many might think, the switch between color and black-and-white isn’t necessarily related to time, rather to perspective: the former is subjective and almost always seen through the eyes of the protagonist, while the second is an objective, analytical lens examining the events that occurred.

The second act goes through the study of and development of the atomic bomb, culminating in the seminal Trinity Test. This sequence is a masterclass in how to build extreme tension and suspense. In a very clever and exponentially more powerful manner, Nolan reminds the audience that sound waves reaching the nearby observers aren’t instantaneous. An explosion at a certain distance implies that its sound only gets to us a few seconds later. Oppenheimer’s climactic moment of truth makes viewers hold their breath during a countdown loaded with intense levels of tension… and continue to hold for a few more seconds, which will make the calmest person in the room quite uneasy.

It’s one of the year’s most unforgettable sequences and it’s brilliantly executed… but beware of unrealistic expectations. The constant talk surrounding the practical recreation of the atomic bomb without special effects generated much anticipation for a moment that should be important for its meaning, not its potential spectacle. Oppenheimer is a superb audio-visual experience, undoubtedly, but those who actually expect to *see* an atomic bomb detonating on the big screen in all its splendor and terrifying grandeur, without any optical obstructions or camera deviations, will inevitably end up disappointed.

The Trinity Test is definitely Oppenheimer’s climactic peak, but the third act is surprisingly as captivating, if not more than the rest of the movie. Nolan chooses to address the personal, political, military, and human consequences of the scientific discovery that changed, forever, how the “new world” looks at war. The moral dilemmas that haunt Oppenheimer for most of the runtime jump – quite literally – to reality and the movie truly becomes a terrifying horror story with sequences so harrowing, disturbing, and scary that it won’t be easy to fall asleep the night after watching this.

Oppenheimer Review

The final few minutes answer questions that had remained ambiguous before in a shocking manner, and Oppenheimer’s deep character study is extended even further. Nolan explores to the fullest all the smallest details of his life and demonstrates, often through glimpses of the protagonist’s imagination, everything that Oppenheimer thinks about his actions, as well as all the people who, in some way, impacted his life. This brings me to one of the reasons, if not the main reason why the film works so damn well: the cast.

There are no words to describe how crucial the contributions of all the actors involved are to the audience’s involvement in the narrative. Oppenheimer treats his characters like the real human beings they were, and the fact that A-listers, Oscar-winning actors show up for just a couple of minutes in a single scene with few lines is a testament to the movie’s strive for authenticity and believably. Countless actors deserve endless praise, but I prefer to focus on the main ones, starting with Murphy.

In addition to an accurately scrawny physical resemblance to the real Oppenheimer, the Irish actor represents the scientist’s moral and ethical complexity with what is probably his career-best performance – a reminder that this is only his second leading role. For example, the chaos caused by the bombs dropped on Hiroshima and Nagasaki is never explicitly seen. Nolan chooses to point the camera to the actor’s face when witnessing photos of the horror experienced in Japan in August of 1945.

Murphy manages to capture Oppenheimer’s mixed emotions perfectly. On one hand, he was responsible for one of the most groundbreaking scientific discoveries in human history. On the other hand, he absolutely feels guilty for the death of thousands of innocent people in a war that, supposedly, was already over. His obsession is analyzed in excruciating detail by Nolan, and the dilemmas that marked his life also passed on to the intimate affairs with his wife Kitty (Emily Blunt) and with Jean Tatlock (Florence Pugh).

Oppenheimer’s events took place during a time when women lacked the respect, rights, and positions of power that, over time, have thankfully changed. Thus, Blunt and Pugh not only have limited screen time but often come across as vulnerable, dependent female characters. Kitty has an incredibly satisfying moment near the conclusion of the movie, but overall, both serve more to emphasize the dichotomy present in the main character’s arc. Pugh is also shown nude in most of her scenes, taking part in some of the weirdest sequences in Nolan’s filmography to date.

Right at the same level as Murphy is Robert Downey Jr. appearing in the black-and-white scenes. After more than a decade of playing a superhero, it’s refreshingly and genuinely fascinating to watch the actor take on the role of Lewis Strauss, a philanthropist who ultimately becomes the story’s antagonist. Despite acknowledging we’re talking about a biopic based on real events and with real people, I still prefer to avoid spoilers for viewers who aren’t aware of the full account – and let’s be honest, the vast majority of today’s audience probably don’t even recognize the name.

That said, RDJ is absolutely fantastic and, like Murphy and Blunt, is unlikely to miss any awards ceremony. Matt Damon plays General Leslie Groves, the military man responsible for the Manhattan Project and recruiting Oppenheimer. The movie possesses rare moments of humor, virtually all of which come from Damon’s performance, through sarcastic comments or ironic attitudes. Oppenheimer is packed with some of the most famous actors alive, so I don’t really need to go around in circles. The bottom line is that everyone is brilliant in their own way in their allocated time.

Aside from occasional problems with Oppenheimer’s unrelenting pacing, as well as its non-linear narrative structure, there isn’t much to pick on in such a well-crafted, well-written blockbuster. Jennifer Lame’s editing is inherently linked to these less positive aspects, but it also contributes greatly to the engaging, intriguing development of the narrative over three hours. A lack of general knowledge about world history, as well as that of the United States of America and its decision making during the WWII era, can bring some complications for those who wish to follow the story without any misunderstandings.

A final note for the outstanding makeup work. At a time when the use of artificial intelligence and de-aging technology is endlessly debated, Oppenheimer demonstrates that digital effects will never be able to beat the incomparable realism of practical effects and cinematic elements. The visualization of the characters is one of the most critical factors in distinguishing the various timelines. I also didn’t notice the sound mixing issue that many complain about in Nolan flicks, but I admit that the fact that subtitles are always available (in the country where I’m watching movies) affects my perception of whether the dialogue is really being drowned out by the background sound or if it’s just my non-native inability to understand everything that is said in the English language anyway.

Final Thoughts

Christopher Nolan’s Oppenheimer is a true masterclass in how to build extreme tension & suspense through fast, detailed dialogue, an insanely powerful sound production, and an equally explosive score from Ludwig Göransson. Words cannot fully describe Hoyte van Hoytema’s gorgeous cinematography. It is a harrowing, disturbing, genuinely frightening story about how one man’s compulsion and political power changed the world. Cillian Murphy, Robert Downey Jr., and Emily Blunt shouldn’t miss any awards ceremonies… they’re absolutely superb, as are the rest of the exceptional actors involved in the movie. Pacing, structure, and runtime, in addition to its quasi-documentary style and its narrative complexity, make this a difficult, heavy watch that will, for sure, leave some viewers disappointed, bored, or simply tired. Ultimately, Oppenheimer justifies the use of the expression “not for everyone”.

Manuel’s Rating: A-
Follow Manuel on Twitter – @msbreviews / Or Letterboxd – @msbreviews

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