Questions tagged [physics]
For questions about the scientific discipline that concerns itself with analysing the laws of nature in full generality
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What are some good references elucidating the discovery/creation of Fourier Series?
I've always grappled with anything related to Fourier since my undergrad days. Recently, when revisiting why I learned what I did, I discovered how Fourier's desire to understand the flow of heat ...
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What is the etymology of the term space-time?
I'm looking for the earliest references to the word space-time (in the modern sense), in any language.
The first references would likely be in German, as Raum-Zeit or Raumzeit.
Of course, H. Minkowski ...
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Who first proposed the theory of tidal locking?
I'm interested in the history of the concept of tidal locking but haven't been able to find any articles presenting a timeline of its development. I'm hoping to have a look at the first published ...
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Why are canonical coordinates canonical?
Canonical coordinates are
coordinates $q_i$ and $p_i$ in phase space that are used in the Hamiltonian formalism. The canonical coordinates satisfy the fundamental Poisson bracket relations:
\...
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Great physicists with no mentors
I often check biographies of physicists and at one point or another in the beginning of their careers they have the opportunity to be mentored by other and often also great scientists. But, I know for ...
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Galileo's Discussion of Uniform Motion
Can someone help me here? the language is archaic. This is (translation of) Galileo
If two particles carried at a uniform rate, the ratio of their speeds will be the product of the ratio of the ...
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Who first solved the classical harmonic oscillator?
There is a question Who solved the quantum harmonic oscillator?, but not one for the classical oscillator. Wikipedia's article Harmonic Oscillator does not have historical information either. So who ...
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Did Kepler arrive at his planetary laws based on Mars's orbit alone?
Kepler apparently arrived at his first two laws based on the Tycho's data for Mars. But Mars has the largest eccentricity except for Mercury, so it is easier to tell the difference between a circle ...
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What is the history behind defining temperature as measure of hotness?
I know that when two bodies of different temperature are kept in contact "heat" flows from hotter body to colder. But how did anyone know that it is the "hotness" that flows, one could have said that ...
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Was the sun assumed to be at rest aether frame?
Back in the past, was the sun assumed to be at rest in the luminous aether frame?
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How did 19th century physicists do their undergraduate/graduate studies?
I have read that
In 1847, he became aware of physicist James Prescott Joule’s argument for the mutual convertibility of heat and mechanical work and for their mechanical equivalence.
We study ...
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How did people react to the realization that Aristotle's ideas had gone without question for way too long?
Recently read the book "Gravity" by George Gamow, in which he says:
For centuries Aristotelian philosophy and scholasticism dominated human thought. Scientific questions were answered by dialectic ...
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Where did Ptolemy compare the Earth to the distance of fixed stars?
I read the following in C. S. Lewis, Miracles (page 77-8)
The immensity of the universe is not a recent discovery. More than seventeen hundred years ago Ptolemy taught that in relation to the ...
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What is the last physics paper or book written in Latin?
What is the last physics paper or book written in Latin? I know Carl Neumann, for example, wrote papers in Latin in the 19th century. Are there any more recently than that?
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Why is Einstein's mass-energy relation usually written as $E=mc^2$, and not $\Delta E=\Delta m c^2$?
Why is Einstein's mass-energy relation usually written as $E=mc^2$, and not $\Delta E=\Delta m c^2$?
When you calculate the energy $\Delta E$ released during nuclear fission, you take the difference ...
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How did Newton come up with his formula?
In high school students are taught the formula that describes the universal gravitational force $F=G\frac{m_1 m_2}{r^2}$. However it is not taught how and why Newton came up with it. Does Newton give ...
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How did Maxwell conclude that light is an electromagnetic wave?
This is a copy of a question I just asked at Physics Stack Exchange. From reading the text on the related questions, it seems that Maxwell equated light with the carrier of electromagnetic force just ...
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How did Planck calculate the Planck constant?
Having started to learn about quantum behavior, this formula came up:
$$E = hf $$
Where $E$ is energy, $h$ is the Planck constant and $f$ is the frequency.
My physics teacher suggested an ...
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When did the use of Sine and Cosine as functions become mainstream?
In the work of early physicists like Newton, everything is explained in terms of cumbersome (in today's standards) geometry. They don't talk about "cosines" of certain angle, but about proportions ...
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Who really discovered/invented the Hooke's law?
According to Wikipedia,
The law is named after 17th-century British physicist Robert Hooke. He first stated the law in 1676 as a Latin anagram. He published the solution of his anagram in 1678 as: ...
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Where does the habit of calling the elements of a projective Hilbert space "rays" originate from?
When describing the projective Hilbert space as the state space in quantum mechanics, physicists habitually refer to its elements as "rays in Hilbert space", while the mathematical literature seems to ...
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Who discovered the normal mode decomposition of coupled oscillators?
Coupled oscillators can be broken down into a superposition of normal mode oscillations. Who was the first person to solve for this system in this way?
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Who introduced the creation and annihilation operators for the harmonic oscillator?
Or who first solved the harmonic oscillator in the algebraic method?
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What are the major flaws of the “caloric” theory of heat?
I was reading about the history of thermodynamics and came across Lavoisier's idea of heat. He proposed that heat was a fluid. I am curious to know what are the major drawbacks of this theory. I know ...
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What is Heaviside's version of Maxwell's equations?
I have read, in many places, statements like this:
Heaviside was able to greatly simplify Maxwell's 20 equations in 20
variables, replacing them by four equations in two variables. Today we
...
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How many papers on general relativity did Marcel Grossmann author or co-author?
Marcel Grossmann is perhaps best known for helping Einstein learn the Riemannian geometry necessary to formulate general relativity. He was instrumental in its early development. Wikipedia states:
...
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Who invented the concepts of potential and kinetic energy? [duplicate]
Who invented potential and kinetic energy ?
Was it Newton ?
Or someone else ?
I have the impression Newton used those ideas but they already existed.
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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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Why do we write $E=mc^2$ and not $E=c^2 m$?
My question goes from Phys.SE where people advised me to ask my question here.
I always learn in maths and physics when something is a constant in an equation we have to put it before which varies. ...
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Did classical physicists feel ill-at-ease about point charges?
The point charge concept is clearly a very useful mathematical fiction, but it is also problematic from the point of view of "physical intuition". Even a layperson would feel that an explanation is ...
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What was the historical importance of the discovery of high-$T_c$ superconductors?
I remember very well from my (only) class in solid state physics how enthusiastically the professor recounted the discovery of high-$T_c$ superconductors. In one particularly vivid anecdote, he ...
Danu♦
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Did Maxwell invent the Maxwell's wheel?
Tried to find it online, but nothing. Everyone refers to it and that it's named after the famous James Clerk Maxwell (of the Maxwell electromagnetic laws and some other things), but there is no direct ...
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Books on the History of Physics
I've just finished reading Quantum: Einstein, Bohr, and the Great Debate About the Nature of Reality by Manjit Kumar, which deals with the history of QM from Plank's quantisation for black body ...
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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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What technology was used to determine the shape of the blackbody spectrum at the 19th century?
The shape of the blackbody radiation spectrum was known in the 19th century from experimental measurements, and before the theoretical discovery of Planck's law.
At those times, how did people manage ...
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What is the origin in the discrepancy between engineers' and physicists' notation of waves?
my question is very simple. Physicists use this notation in order to write a (for example) plane wave:
$$
\xi(z) = \xi^+ \mathrm{e}^{+\mathrm{i}kz} + \xi^- \mathrm{e}^{-\mathrm{i}kz},
$$
where $\xi^+$ ...
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What are some concepts/discoveries in mathematics and science that found practical application years after they had been formulated/discovered?
I'm looking for examples of ideas/discoveries/concepts in Maths or Science that had no practical application at first and were maybe considered as nothing but a theoretical concept but they turned out ...
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Where did the false "equal transit-time" explanation of lift originate from?
It's supposedly a "widely circulated" false claim that wings generate lift because of their asymmetric shape, forcing air above to travel faster so that they meet up on the trailing edge at the same ...
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How did Huygens derive the conservation law for of kinetic energy?
In the book 'Energy - The Subtle Concept' by Energy, the Subtle Concept by Jennifer Coopersmith the author says that Huygens was the first to use the term $mv^2$ in physics. He was considering elastic ...
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Why historically the hour was divided into 60 minutes and when it had started? [duplicate]
Why and when was the hour divided into exactly 60 minutes (and not for example 70 or 80)?
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How did Stern or Gerlach, of Stern-Gerlach experiment, create individual silver atoms? How were they accelerated?
How, a century ago, could Stern and/or Gerlach KNOW that they had created single silver atoms?
How were they moved, or accelerated?
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Equivalence principle before Einstein [duplicate]
In a German interview some physicists were asked, what they would ask Einstein, if he were alive today. One of them wanted to know how Einstein came up with the idea of the equivalence principle, that ...
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How were negative numbers first used in physics?
The use of negative numbers in most of today's calculations is natural. But how did the use of negative numbers began in physics? What physical quantity required the introduction of negative numbers ...
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Who first derived $a =v^2/r$
This is a basic formula in mechanics, which determines the acceleration of a particle performing uniform circular motion.
By who first derived it? In Newton's Principa, what one can find is that
$$...
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When did error propagation become prominent in physics?
I think is well known that greek scientists and even founding fathers of modern science did not use error propagation in their calculations. Today, instead, is unacceptable to work out any prediction ...
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What did it historically mean in physics for something to "exist"?
What is the history of influential definitions of objective existence --- This Is Real, It Exists --- in physics? Where did they appear in the literature and in what context were they put forward?
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What made Einstein believe (or know) that time was affected by speed and gravity?
How did he come up with this idea before there was any experimental data to prove this?
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On the development of Newtonian Mechanics
Having borrowed from the library an English translation of Newton's Principia (Motte's), I read the begining sections, Part 1 and the Systems of the world, and noticed that Newton did physics ...
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Have there been instances in physics where different scientists have interpreted the same data differently? [closed]
Have there been instances in physics where different scientists have interpreted the same data differently? If yes, can you please give me specific examples and explain why one interpretation was ...
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Was Captain Cook’s voyage to observe the transit of Venus going to enable better ship navigation at the time?
On a recent visit to the Royal Observatory at Greenwich I was struck by its proximity to the Naval Academy next door. The theme of the history of clocks and development of astronomy was driven by the ...
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