Questions tagged [physics]
For questions about the scientific discipline that concerns itself with analyzing the laws of nature in full generality. It is one of the largest branches of natural science. Before applying this tag to a question, please consider using the "theoretical-physics" or "experimental-physics" tags instead, as they are more descriptive.
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Einstein's handwritten manuscript on General Relativity
The book "The Road to Relativity" by Gutfreund and Renn annotates Einstein's original handwritten manuscript from 1916 - "The Foundation of the General Theory of Relativity." I can ...
2
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1answer
315 views
Why does Riazuddin not have a last name?
Riazuddin was a Pakistani theoretical physicist, his name looks a little bit different to me from others because he doesn't have a last name. There are some others Pakistani theoretical physicists ...
3
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1answer
528 views
How did J.J. Thomson learn that what he discovered was different than an atom or a molecule?
Wikipedia says he discovered that the electron was different than an atom or molecule. His line of reasoning is not shown. I additionally searched stack exchange and unless I missed it.....
I am lost ...
3
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1answer
87 views
Where exactly did George Brown publish the first paper about Turnstile antennas?
In its most basic form the Turnstile antenna is two half-wave dipole antennas that are perpendicular and driven 90 degrees out of phase. For a recent review see Crossed Dipole Antennas: A review (also ...
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1answer
106 views
Was de Broglie, the physicist who suggested matter behaves like waves, a prince? [closed]
Hi guys, I've been reading about the wave-particle duality of matter, and I came across this statement that said de Broglie was a prince. Is that true?
3
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0answers
53 views
Different versions of mass during early years of special relativity
My question is basically about four different versions of mass from the early years of special relativity when the concept of relativistic mass was acceptable. I'd appreciate it if you try to keep ...
3
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0answers
51 views
Was the wide use of mercury in experiments in the 19th century related to alchemy?
We know that Newton's hair samples showed high level of mercury and of course he used mercury like crazy in his alchemy experiments (as did many/all alchemists not just in the west but also China) and ...
3
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2answers
121 views
Why did energy-momentum relationship have to wait until 1928 to be established?
This web page shows how to derive energy-momentum relationship, $E_{total}^2=p^{2}c^{2}+\left( mc^{2}\right) ^{2}$, given the following equations. Please note that some sources make a distinction ...
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31 views
What was Claudio Bunster's role in the Human Rights Commission in Chile?
Claudio Bunster, a Chilean physicist, was educated in the University of Chile and Princeton. He returned to Chile when the Pinochet dictatorship was at its height and, against all expectations, and ...
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2answers
137 views
Why isn't the history of mechanics dated from Archimedes time?
It's often said - and more often written - and perhaps, even more spoken of - that modern physics began with Galileo due to his application of mathematics to motion. This is the position taken by ...
3
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2answers
65 views
What was known about the properties of the nucleus before the Liquid drop model was proposed?
What was known about the properties of the nucleus (its shape, its density etc) and the nuclear forces before the Liquid drop model was proposed? I believe that some empirical knowledge must be out ...
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164 views
kinetic energy formula written as mv^2
I stumbled across the following quote and couldn't understand how one wouldn't use the factor of 1/2 without completely disrupting the work-energy principle. Though, informal, energy is defined as the ...
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1answer
73 views
Where did the contour integral sign appear for the first time?
A simple question: Where did the contour integral sign appear for the first time?
Wikipedia says that it was introduced by physicist Arnold Sommefield in 1917 ( Table of mathematical symbols by ...
2
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1answer
118 views
Is string theory today facing the same backlash that atomic theory faced during its inception?
I read in this Quanta article that although many critics say that it is far removed from nature, it has developed many powerful tools. Furthermore some don’t care if it’s a theory of everything and ...
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0answers
66 views
Some questions about radioactivity around 1900
All the questions are closely related to each other therefore, in my opinion, it wouldn't make much sense to ask them separately. I'm trying to find the answers in historical context. I appreciate ...
1
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1answer
67 views
Are “galvanic” and “voltaic” synonymous?
The OED defines galvanism (coined ~1792) as
Electricity developed by chemical action
and voltaic (coined ~1813) as
Used in producing electricity by chemical action after the method discovered by ...
3
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1answer
72 views
Why do we use $U$ for potential energy in classical mechanics?
I am unaware if someone has asked this before, but I am studying classical mechanics and I don’t know why do we use $U$ for potential energy. I have read that Rankine used it first, but I can’t find ...
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1answer
65 views
What are the stories of physicists's prediction of problems that future generation will be busy with/topics that revolutionize future of physics?
There are stories that famous physicists made predictions of a list of problems; problems that the future generation of physicists will be busy with or revolutionize the future of physics in the ...
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0answers
49 views
How did Millikan consider utilizing oil to help determine the charge of the electron?
Robert Millikan's oil drop experiment help to find the charge of electrons using oil. An x-ray was aimed at the oil drops to give them a charge, and the droplets were attracted to the negative plate. ...
3
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1answer
426 views
Who made the first derivation of the angle to maximise projectile range, which turned out to be wrong?
I remember hearing once that the first "proof" that the angle to maximise projectile range gave the correct answer, 45 degrees, but was later found that the proof was wrong. I can't remember ...
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2answers
385 views
Why are there so many German terms in the field of radiative transfer?
A lot of phenomena in radiative transfer are named after a person who studied them (Rayleigh scattering, Mie scattering, Bragg diffraction, Kikuchi lines, Tyndall effect,...). Others are designated by ...
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83 views
On atomism and philosophy of science
The background of this question is as follows. Sean Carroll is in the process of giving a series of talks recorded in his home office and published on YouTube. The setup is intentionally very informal....
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1answer
87 views
Did Galileo use an erroneous geometrical result in 'Two New Sciences'?
In Thm. 4, Prop. 4 of Galileo's 'Two New Sciences' (pg. 187, Crew Translation), Galileo says the following: "From a single point $B$ draw the planes $BA$ and $BC$, having the same length but ...
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1answer
124 views
Einstein: 'SR is a theory of invariants, not relativity' — source?
It is occasionally remarked that Einstein was unhappy that SR became referred to as a ‘theory of relativity’, when in his eyes it was, much more importantly, a theory of invariants (Invariantentheorie)...
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1answer
100 views
Why is it that so many early astronomers and cosmologists wanted to believe in a static/infinite/eternal Universe?
I've been doing some research for a cosmology series and I'm struck by how many physicists and philosophers, from Newton to Einstein, had a notion that the Universe should be static and eternal. Why ...
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1answer
95 views
Who studied kinematics before Galileo? Did Galileo base his kinematic research on the previous work of any other scientist?
Galileo is known to have studied kinematics through his work with projectiles. How did he first consider researching motion and velocity? Was he inspired by previous work done by earlier scientific ...
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76 views
Was Lagrange the first to have used generalized coordinates?
I was wondering if Lagrange was the first to use generalized coordinates as defined by their wikipedia article.
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50 views
When was the first analysis of the single-slit experiment done using wave theory?
I am a bit confused by the history here.
We know that in early 1800's Thomas Young performed the double-slit experiment to demonstrate light interference. After wave theory of light became more ...
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2answers
1k views
Heisenberg's Obituary to Pauli
In an interview of Heisenberg by Thomas Kuhn:
When Pauli had died, I was asked to write this memorial volume. Weisskopf had asked me. Then, actually, originally I had written an article on Pauli's ...
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2answers
6k views
Who is the lady on the image? [closed]
I stumbled upon the following napkin (yes, a napkin) and was wondering who the lady on the picture is:
She is surrounded by some basic mathematical functions, as well as physical equations which ...
4
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0answers
74 views
Who introduced the comma notation for partial derivatives?
In general relativity, it is common to use the comma notation for partial derivatives
$$\frac{\partial g_{\mu\nu}}{\partial x_\rho} = g_{\mu\nu_,\rho}$$
Where did this notation first appear? Was it ...
2
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0answers
49 views
Did Rydberg ever learn of Bohr's quantum-mechanical explanation of his formula?
The Rydberg formula on the wavelengths of a spectral line in chemical elements was first stated empirically in 1888 by Johannes Rydberg. A theoretical explanation of the formula wouldn't arive until ...
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48 views
How did percolation theory come to be established in network science, and who first studied it?
According to the textbook "Network Science" by Albert-László Barabási, percolation theory is a specialized branch of both mathematics and physics [1]. It involves node clustering in a ...
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2answers
121 views
Is there an etymological dictionary of terms in physics?
There are of course many physics dictionaries and glossaries and some words can be found in general etymological dictionaries and even English dictionaries; but is there a Physics Etymological ...
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66 views
What is the original source of the problem of finding equivalent resistance between two nodes in an infinite grid of resistors?
A famous problem in electronics or physics course,is the following---
Consider an infinite 2d grid of resistors having resistance of equal value.Find the resistance between any two nodes in the grid.
...
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0answers
69 views
“Nuclear fusion is 30 years away” since when?
It's a well-known, running joke (or criticism) in the fusion community that
Fusion is always 30 years away.
refering to the considerable difficulties that harnessing nuclear fusion as an energy ...
3
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1answer
81 views
Who established that $K_e = \frac{1}{4 \pi \varepsilon _m}$?
Coulomb's Law states that :
$$F_e = K_e\dfrac{q_1q_2}{r^2}$$
where $q_1$, $q_2$ are magnitudes of the two point charges, $r$ is the distance between them and $K_e$ is
Coulomb's Constant (aka ...
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0answers
58 views
How transparency was explained by corpuscular theory and Young/Fresnel's wave theory
How did the light theories of Newton and Young/Fresnel explain the transparency of materials such as glass, or opacity of materials such as paper and wood?
Newton's theory of light was largely based ...
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1answer
103 views
Which conception of a “machine” allows to call “mechanical” the new physics of the 17th century?
My questions deal more properly with pre-Newtonian modern physics in its Cartesian or Hobbesian versions.
The word "mechanical" comes from a Greek word meaning "machine". However, the received ...
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50 views
Fresnel's partial aether drag hypothesis
In 1810, François Arago realised that variations in the refractive
index of a substance predicted by the corpuscular theory would provide
a useful method for measuring the velocity of light. These ...
2
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0answers
100 views
Where can I find Lagrange’s original equilateral triangular solution for arbitrary masses?
This answer to What kind of triangle is formed by three unequal masses in a circular restricted three body orbit? explains that
In the Newtonian limit, an equilateral 3-body solution exists for any ...
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0answers
62 views
How has the degree of mathematisation in physics university education in the U.S. changed in the 20th century?
I'm mostly interested in the degree of mathematisation with which physics was taught. Intuitively, I believe to recall that Europe has had a long tradition of mathematical physics, while physics ...
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1answer
98 views
Quantum chromodynamics - an origin of the name
A theory of strong interaction is called quantum chromodynamics (QCD). Particles interacting strongly are supposed to have color charge, for example quarks appear in three "mutations" - red, green and ...
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0answers
116 views
Origin of Fourier Transform (1878)
I located Joseph Fourier's book, Analytial Theory of Heat (1878), but at first glance it looks like it is all about heat. What did Fourier call the Fourier transform? When did he first use it?
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1answer
59 views
How was a material independent temperature scale created?
Temperature measurements started with the developments of thermoscopes and thermometers. They were based on the fact that liquids in general expanded significantly on change in temperature (especially ...
4
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1answer
99 views
Was Joseph Priestley “isolated”
Joseph Priestley is often said to have discovered Oxygen, or not due to calling it Dephlogisticated air - depending on one's preference. However, regardless of this, it is often said in popular ...
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60 views
Did the mathematician Garrett Birkhoff ever work with or mention Feynman's path integrals?
Did Garrett Birkhoff ever work with Feynman's path integral? Did he ever work in his Many-Histories interpretation? Or at least, did he mention it in any of his articles?
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2answers
164 views
How did Newton prove his third law of motion?
I guess it is an experimental law, so what was the experiment?
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1answer
205 views
Natura non facit saltus (nature does not make jumps), who said that?
The sentence is Latin for nature doesn't make jumps. It refers to the fact that, in most physical processes, quantities vary continuously.
The principle was used by Leibniz, Kant and Darwin among ...
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0answers
48 views
Use of kT for energy of a wave?
The energy of $\frac12kT$ for each degree of freedom of a particle from statistical mechanics was derived from particles, and yet Rayleigh and Jeans just nonchalantly said let's borrow this and apply ...
