Richard Feynman's blackboard, preserved after his death in 1988, offers a glimpse into his final thoughts and ongoing work. It features a partially completed calculation related to the quantum Hall effect, specifically concerning the motion of a single electron in a magnetic field. The board also displays a quote from "King Lear" – "What art thou that dost torment me in this world" – alongside a drawing and some seemingly unrelated calculations, hinting at the diverse range of topics occupying his mind. The preserved blackboard serves as a poignant reminder of Feynman's relentless curiosity and enduring engagement with physics.
Hans Bethe, renowned for calculating stellar energy production, surprisingly found success by applying simplifying assumptions to complex quantum problems. He tackled seemingly intractable calculations, like the splitting of energy levels in magnetic fields (Zeeman effect) and the behavior of crystals, by focusing on the most dominant interactions and ignoring smaller effects. This approach, though approximate, often yielded surprisingly accurate and insightful results, showcasing Bethe's knack for identifying the essential physics at play. His ability to "see through" complicated equations made him a pivotal figure in 20th-century physics, influencing generations of scientists.
Hacker News users discussed Bethe's pragmatic approach to physics, contrasting it with more mathematically driven physicists. Some highlighted his focus on getting usable results and his ability to simplify complex problems, exemplified by his work on the Lamb shift and stellar nucleosynthesis. Others commented on the article's portrayal of Bethe's personality, describing him as humble and approachable, even when dealing with complex subjects. Several commenters shared anecdotes about Bethe, emphasizing his teaching ability and the impact he had on their understanding of physics. The importance of approximation and "back-of-the-envelope" calculations in theoretical physics was also a recurring theme, with Bethe presented as a master of these techniques.
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https://news.ycombinator.com/item?id=43131017
HN users discuss the contents of Feynman's blackboard, focusing on the cryptic nature of "Know how to solve every problem that has been solved." Some interpret it as a reminder to understand fundamental principles rather than memorizing specific solutions, while others see it as highlighting the importance of studying existing solutions before tackling new problems. A few users point out the irony of the seemingly unfinished thought next to it, "What I cannot create, I do not understand," speculating on what Feynman might have intended to add. Others comment on the more mundane items, like the phone numbers and grocery list, offering a glimpse into Feynman's everyday life. Several express appreciation for the preservation of the blackboard as a historical artifact, providing insight into the mind of a brilliant physicist.
The Hacker News post titled "Richard Feynman's blackboard at the time of his death (1988)" generated several interesting comments discussing the contents of Feynman's blackboard and reflecting on his genius.
Several users attempted to decipher and interpret the equations and notes on the board. One user pointed out the notation "d(amplitude)/dt," suggesting Feynman might have been working on something related to quantum mechanics, specifically, how the amplitude of a quantum state changes over time. This user also speculated about the significance of other notations like "∇ψψ*" potentially representing probability currents, further reinforcing the idea that he was engaged in quantum-mechanical calculations. Another user focused on the diagram featuring labeled points 'A', 'B', and 'C', interpreting it as potentially related to scattering amplitudes or path integrals, key concepts in Feynman's work. The discussion included some debate about whether the diagram represented an electron emitting a photon or some other particle interaction.
Beyond the technical interpretations, many comments reflected on Feynman's working style and the unique glimpse into his mind provided by the blackboard. One user remarked on the seeming randomness and exploratory nature of the notes, suggesting Feynman's process involved freely exploring ideas and connections. Another comment highlighted the simplicity of the tools Feynman used, just a blackboard and chalk, contrasting it with modern computational methods. This sparked a small thread discussing the merits of working through problems by hand versus relying on computers.
Some users shared personal anecdotes related to Feynman, including one recounting a story about Feynman's emphasis on understanding concepts deeply rather than just memorizing equations. Others simply expressed admiration for Feynman's intellect and contributions to physics, with one calling the blackboard photo a "beautiful and poignant relic."
A couple of comments offered links to further resources, such as a collection of Feynman's lectures and a discussion about the specific problem he might have been working on.
Overall, the comments provide a fascinating mix of technical analysis, personal reflections, and shared appreciation for Richard Feynman's remarkable mind. They offer a glimpse into how others interpret the remnants of his thought process and the lasting impact of his work.