Physics In History

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Imagine solving 357 years old mathematical problem that other mathematicians said "impossible to prove".

But in my opinion, all things in nature occur mathematically. - René Descartes

In your opinion, why did Newton never marry? ✍️

If I were not a physicist, I would probably be a musician. I often think in music. I live my daydreams in music. I see my life in terms of music... I get most joy in life out of music. - A. Einstein

Physicist Richard Feynman was a prankster and a joker. He enjoyed playing practical jokes on his colleagues and friends, such as cracking safes, picking locks, and impersonating other people. He also liked to make fun of himself and his own mistakes. He once said, "The first principle is that you must not fool yourself and you are the easiest person to fool" 📷 Feynman at CERN around 1954, courtesy of CDS

The Big Bang theory says nothing about what banged, why it banged, or what happened before it banged. -- Alan Guth

Doing nothing vs Small consistent effort ✍️

Long before general relativity made curved space famous, Boltzmann lectured on the conceptual foundations of non-Euclidean geometry as early as the 1870s. He saw its potential not just as a mathematical curiosity but as a way to rethink the continuum in physics—anticipating later work by Einstein and others.

Fun Fact: Louis Pasteur, a remarkable French scientist who made significant discoveries and inventions in the fields of chemistry, microbiology, and medicine was not a good student in his early years. He failed his first attempt at the entrance exam for the École Normale Supérieure, a prestigious institution for higher education in France. He also struggled with mathematics and physics, and only obtained mediocre grades in his general science degree. 📷unknown

In your opinion, does the universe have a purpose ? ✍️

Richard Feynman explaining atoms and stars in this ‘Fun to Imagine’ BBC series, recorded at Feynman's home in Altadena, California, ca. 1983 🧠 - 📹 BBC Archive

“We cannot solve our problems with the same thinking we used when we created them.” - Albert Einstein

J. Robert Oppenheimer lecturing at Kyoto University, Japan on September 14, 1960.

Albert Einstein visited the Hopi people near the Grand Canyon in 1931, where he was honored with a feathered headdress and a peace pipe at Hopi House. The gesture recognized his pacifist ideals and is preserved in a well-known photograph.

Richard Feynman on the meaning of life ✍️

Happy 108th Birthday to the brilliant Richard Feynman. —one of the most charismatic physicists of the 20th century, best known for his foundational work in quantum electrodynamics (QED), for which he shared the 1965 Nobel Prize in Physics. He had a rare gift for making complex ideas feel intuitive, developing the famous “Feynman diagrams” as a visual shorthand for particle interactions. Beyond his science, he was a celebrated teacher, bongo drummer, safe-cracker, and storyteller—a genuinely curious, irreverent personality who believed that the joy of discovery was inseparable from understanding itself. His lectures at Caltech remain legendary, and books like Surely You’re Joking, Mr. Feynman! capture his infectious delight in figuring out how the world works.

In 1939, Adolf Hitler was nominated for the Nobel Peace Prize. It was actually meant as sarcasm by Swedish MP E.G.C. Brandt to protest appeasement politics. The outrage was immediate, and the nomination was withdrawn. No Peace Prize was awarded that year.

Quantum decoherence is the process where a quantum system loses its superposition due to interactions with its environment. This doesn’t "collapse" the wavefunction but entangles the system with its surroundings, making quantum interference unobservable. As coherence fades, classical behavior emerges, explaining why we don’t see quantum superpositions in everyday life.

The big bang vs. Steady state theory 🌌 The big bang theory and the steady state theory are two competing models of the origin and evolution of the universe. They differ in their assumptions, predictions, and evidence. The big bang theory assumes that the universe began in a singular point of infinite density and temperature, which exploded about 13.8 billion years ago and has been expanding and cooling ever since. The big bang theory predicts that the universe should have a finite age, a dynamic history, and a cosmic microwave background radiation (CMBR), which is the remnant heat from the initial explosion. The big bang theory also explains the observed abundance of light elements such as hydrogen and helium, which were formed in the first few minutes after the big bang. The steady state theory assumes that the universe has no beginning or end, and that it is eternal and unchanging. The steady state theory predicts that the universe should have a constant density, a constant rate of expansion, and no CMBR. The steady state theory also proposes that new matter is continuously created in the space between the galaxies, to maintain the constant density. The evidence for and against these two theories is based on various observations of the universe, such as the CMBR, the redshift of distant galaxies, and the abundance of light elements. The CMBR is a very strong evidence for the big bang theory, as it matches the predicted spectrum of radiation from a hot and dense early universe. The redshift of distant galaxies is also consistent with the big bang theory, as it indicates that the universe is expanding and that it was smaller and denser in the past. The abundance of light elements is another evidence for the big bang theory, as it agrees with the calculations of nuclear reactions in the early universe. The evidence against the steady state theory is mainly based on the lack of observed new matter being created in the universe. If new matter was being created, it would have a different distribution and composition than the existing matter, which would be detectable by various methods. However, no such evidence has been found, which contradicts the steady state theory. Moreover, the steady state theory cannot explain the CMBR, which is observed in all directions of the sky. The steady state theory also fails to account for the observed abundance of light elements, which are too low to be explained by continuous creation. The current status of the debate over these two theories is that the big bang theory is widely accepted by the scientific community as the best explanation for the origin and evolution of the universe. The steady state theory has been largely abandoned by most cosmologists, as it has been falsified by many observations and experiments. However, some variations and modifications of the steady state theory have been proposed by some researchers, such as the quasi-steady state cosmology, which tries to incorporate some aspects of both theories. 📷NSCL/flickr

Einstein’s 1905 relativity paper originally had no citations. The paper “On the Electrodynamics of Moving Bodies” (Annalen der Physik, 1905) was about 9,000 words (30 pages in journal format), but it had no references at all — very unusual for a physics paper.