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29 views

Ludwig Prandtl'S student [on hold]

a daughter of Ludwig Prandtl in a book about her father mentions that he had a PhD student who was in the Eastern front and corresponding with her father/ writing his PhD is the name of this student ...
1
vote
1answer
67 views

Is there a historical name for an inductor that starts with the letter $L$? (RL circuits) [closed]

Why is a circuit with a resistor and inductor called an RL circuit and not an RI circuit? Was there a now-obsolete name for an inductor that started with the letter $L$?
0
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3answers
68 views

Source of “Physics is solved” quote [closed]

I have a vague memory of some prominent scientist in the time just before quantum mechanics got going bragging that physics was solved except for a few edge cases and some slightly more precise ...
6
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0answers
56 views

Why is equipartition law called a theorem too, in some books? [closed]

In some books, the equipartition law is called a theorem. But a law is an observation, and cannot be proved. On the other hand, a theorem is something established using earlier assertions. So what ...
1
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0answers
40 views

Have there been any patented physical models or computational algorithms? [closed]

There was a recent question (linked below) on the Law SE about the potential to patent algorithms. It appears there is a lot of gray area in the subject. Of course natural laws cannot be subject to ...
36
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3answers
8k views

What was the 'quantum mechanics' before quantum mechanics?

Quantum mechanics is near-universally considered one of the most difficult concepts to grasp, but what were the persistently unintuitive, conceptually challenging fields physicists had to grasp before ...
1
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1answer
122 views

Meaning of a remark by Heisenberg: Die “Bahn” entsteht erst dadurch, dass wir sie beobachten

In a paper by Joos and Zeh, Z Phys B 59 (1985) 223, they say: This 'coming into being of classical properties' appears related to what Heisenberg may have meant by his famous remark [7]: 'Die "Bahn"...
3
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2answers
137 views

How much of the standard model could have been discovered in a world without computers?

Computers were not needed for the discovery of quantum mechanics (1920s) or general relativity (1910s), and the standard model was proposed when computers were much less powerful than today (1970s). ...
2
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1answer
167 views

What is the etymology of the term “amplitude” as used in quantum mechanics?

Some people claim that the single most important conceptual point in all of quantum mechanics is that "probability amplitudes" (inner products) can be complex, as opposed to strictly positive. But in ...
1
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1answer
114 views

Quote from Genius

In Genius Season 1 Episode 1 at 9:00, Young Albert Einstein defies his teacher by solving the equation on board and states Natural log of constant multiplied by x equals natural log of one plus v ...
1
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0answers
46 views

History of thought experiments [closed]

I am writing a little article about thought experiments through the history of physics (university level); more specifically, from the times of Thales of Miletus (~ ancient Greeks) to our day. I want ...
1
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0answers
23 views

Reference for biography of Philipp Lenard [closed]

I was asked to write about the physicist Philipp Lenard, known for his research with cathode rays and as a winner of a Nobel prize, but i wasn't able to find good references (with exception for those ...
7
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3answers
327 views

What parts of a physics undergraduate curriculum have been discovered since 1966?

What parts of an undergraduate curriculum in fundamental physics have been discovered since, say, 1966? (I'm choosing this because it's 50 years ago.) Physics textbooks have moved on since 1966 (...
21
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1answer
1k views

Why are gauge theories called so?

Why are gauge theories called so? I guessed it was because gauge also means to estimate, so when one is trying to find the gauge theory for such and such interactions one has to estimate what might be ...
21
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3answers
3k views

Was the understanding of QM fundamental to the creation of transistors and silicon semiconductors?

Without quantum mechanics there would be no transistor, and hence no personal computer; no laser, and hence no Blu-ray players. James Kakalios, a physics professor at the University of Minnesota, ...
8
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1answer
2k views

Why does math work for describing and solving physics problems? [closed]

The clarified version As far as I understand, Wigner considers a "miracle" the fact that it is even possible to find a mathematical equation that describes a natural phenomenon. It is not exactly ...
4
votes
1answer
946 views

Why didn't Newton study electricity and magnetism?

This is a soft question about the history of physics. In Newton's time, electrical and magnetic phenomena (such as amber attracting things or the alignment of compass needles) were well known. Yet I ...
-2
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2answers
72 views

Reference request: history of models and equations? [closed]

I am looking for an in-depth self-contained text for the layman which covers the historic development of major questions in physics and the models and equations considered to answer them, and their ...
-1
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2answers
2k views

Is electromotive force really a force? [duplicate]

As far the definition goes emf of electromotive force is basically potential difference. It even has dimensions of potential. Then why is it called a force?
2
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0answers
185 views

Which problem is Oppenheimer working on in this picture? [closed]

Does anybody recognize the equations on the blackboard? Above his hand, with the $\gamma_k$ term and its complex conjugate, it looks like a written out matrix representation of a Hamiltonian $U$, ...
-2
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2answers
177 views

Has Dirac ever co-authored a paper? [closed]

Just curious. Not counting PhD theses, books, and review papers, but regular research papers with original ideas.
1
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1answer
202 views

Was quantum mechanics made to fit the Bell violations or they just happen to fit them?

Entangled bipartite states can violate the CHSH inequality by up to $2\sqrt{2}$ with suitable measurements. Is it that in nature we don't witness violation of CHSH more than this and quantum mechanics ...
6
votes
1answer
359 views

When was the first time that superconducting quasiparticles were called Majorana fermions?

Since a number of years, the field of superconductivity has a growing obsession with Majorana fermions. I wonder how far back we can go: When was the first time that superconducting quasiparticles ...
2
votes
1answer
782 views

What was Feynman's famous formula?

In Welton(1983), Memories of Feynman, Welton mentions two formulas which he denotes as Feynman's Famous Formula (FFF) and FFF #2. Which famous formulas is he talking about? Is he maybe talking about ...
5
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0answers
405 views

Why is an Ampere an SI unit? [duplicate]

It has always annoyed me that an Ampere is an SI unit, rather than a Coulomb. Why is this the case? Was current discovered first historically? I believe that the standards were published in the 1960s, ...
3
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0answers
93 views

When did people start to regard “time” as a physical quantity? [closed]

I was trying to figure out how people came to know about time then I realized that people started keeping track of time to know about sunset and sunrise. But I can't figure out how did time came into ...
2
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1answer
131 views

Prerequisites for Ptolemy's Almagest

I hope this is a valid question to ask on this website (since it's astronomy and not e.g. mechanics, I wasn't so sure). What prerequisites are needed for fully understanding Ptolemy's Almagest. Fully ...
39
votes
2answers
14k views

What are Stephen Hawking's main contributions to research-level physics?

Without a doubt, Stephen Hawking is the most famous living scientist; indeed, his public visibility in all of history seems to be rivaled only by Einstein and easily eclipses giants of physics such as ...
2
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0answers
84 views

Which scientists have managed to name their laws/terms after themselves? [closed]

It would be pretty vain for someone to name a scientific law, unit, or term after themselves. "Newtons" as the name for the measurement of force, for example, was adopted in 1948, so I don't expect ...
1
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2answers
193 views

Norsk Hydro and heavy water - what was the perceived threat?

Through various raids and acts of sabotage during WWII, the Allies succeeded in preventing Germany from coming into possession of large quantities of heavy water produced by the Norsk Hydro plant in ...
2
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0answers
286 views

Story about a mathematician, a dinner party, and the three-body problem

I remember dimly hearing a story, coincidentally also at a dinner party, and I was trying recently to track the details down with no success. I was hoping someone here might have also heard this story ...
3
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3answers
1k views

Who proposed the bulk-edge correspondence principle?

Who proposed the bulk-edge correspondence principle? The principle is often quoted in counting the number of zero energy states localized on the interface between two insulators with distinct band ...
4
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1answer
952 views

Why does the BB84 paper “Quantum cryptography: Public key distribution and coin tossing” have a 'withdrawn' status?

The original paper proposing quantum key distribution protocol (now known as BB84): Charles H. Bennett, Gilles Brassard, Quantum cryptography: Public key distribution and coin tossing seems to have <...
1
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2answers
224 views

Origin of the word Permittivity

Who coined the word "permittivity"? It appears that first usage was in 1887. Please cite your source.
3
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0answers
111 views

Dingle vs. Bondi: Twin Paradox Debate on BBC radio?

Herbert Dingle and H. Bondi debated the twin paradox on BBC radio before 1971. Does anyone have a link to the audio of this debate? thanks
0
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1answer
91 views

Why so much geometry in principia and others

I was recently reading 'On the the shoulders of giants' by stephen hawking and looked at many physics(mechanics) problems solved by Copernicus,Newton etc. why is there so much of geometry used by them....
8
votes
2answers
515 views

Where does this term “shell” with prefix “on-/off-” come from?

Is there some historical reasons or is there a specific reason behind it? This question is connected to: Why on-shell vs. off-shell matters?
1
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1answer
684 views

How big was the first transistor?

The first working point-contact transistor made in 1947 by Bell Labs. I'm looking for specific dimensions, all I've been able to find is "Fits in the palm of your hand".
4
votes
1answer
325 views

Why have $n$, $\ell$, $m_\ell$, $m_s$ been picked as quantum number symbols $\mathbf{\text{in this order}}$?

I’m learning about electron configurations and don’t quite understand why $n$, $\ell$, $m_\ell$, $m_s$ have been picked as symbols for the quantum numbers. As far as I understand it, the principal ...
2
votes
1answer
179 views

Who popularized $E=mc^2$?

When asking a layman for a mathematical or physical equation you will almost certainly get the answer "$E$ equals $m$ $c$ squared". In fact, $E=mc^2$ is something like a symbol of physics in popular ...
0
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1answer
178 views

Are there correct physical predictions made only from thought experiments other than in General Relativity? [closed]

When Einstein started to think about gravitation, he completely created a new theory that no experiment supported. He based his reasoning, as he explained it later, on small thought experiments (...
7
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2answers
297 views

Development/history of Mesoscopic Physics/quantum transport

I am studying mesoscopic physics/quantum transport. Now I am wondering (out of interest): how did this field emerge and what made it such a huge field? I couldn't find this somewhere clear on the web ...
4
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0answers
1k views

Why the letter $B$ for magnetic fields? [closed]

Is there a reason behind the usage of this letter to represent magnetic fields, or is it a randomly made choice?
1
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0answers
45 views

What were the immediate consequences Yang-Lee work on Weak Interaction?

I am studying the history of Modern Physics and Yang-Lee earned their Nobel the next year after the Cobalt experiments. I am familiar with the chronology, but am not clear what those findings meant to ...
7
votes
2answers
448 views

Who is usually credited for the creation of QFT?

I read in a book just now that says: [...] but it was not explained until the invention of quantum field theory by Richard Feynmann [sic] and others in the 1940's. I have been under the impression ...
3
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0answers
458 views

Why supra-conductivity became super-conductivity?

The original article by the Kamerlingh Onnes team in Leiden does not give a name to the new effect: Kamerlingh Onnes, H. Further experiments with liquid helium. C. On the change of electric ...
2
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2answers
803 views

Why are lab Magnets painted red? [closed]

Wy are lab magnets painted red in color? I tried searching everywhere but couldn't get a satisfactory answer.
11
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2answers
2k views

Historical reason behind using $ν$ instead of $f$ to stand for frequency in the equation $E=hν$?

Normally, we use the letter $f$ to stand for frequency in equations. $$T = 1/f$$ $$v = \lambda f$$ $$Φ +E_k = h f$$ So I'm curious as why the letter $ν$ (nu) is used to represent frequency in the ...
1
vote
1answer
136 views

Obtaining a measurement very indirectly [closed]

While answering a question I came to reflect on the fact that in science experimental setups measure things indirectly. Example: the setup of the Pound-Rebka experiment. The amount of absorption was ...
2
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0answers
90 views

How would Einstein's later years have been different with modern computers? [closed]

This is a historical question partly, and maybe too broad for this site, but would require some familiarity with modern physics research practice so hopefully appropriate here. Einstein's later ...