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22

Hamilton and Klein, Klein was more explicit about it. Hamilton in Lectures on Quaternions (1853) realized that his representation of rotations of rigid bodies by the unit quaternions was not $1$-$1$, but $2$-$1$. Klein in Lectures on the Ikosahedron and the Solution of Equations of the Fifth Degree (1888) replaced the unit quaternions by $2 × 2$ unitary ...


19

It is not random. These names are of Greek origin, and -ic or -ics are Anglicizations of the Greek suffix -ikos, which meant "pertaining to". In other languages it can be rendered as -ika or -ica, Wolfram's "Mathematica" uses such a version. From the Online Etymology Dictionary: "-ics in the names of sciences or disciplines (acoustics, aerobics, ...


15

Max Planck, Scientific Autobiography and Other Papers (Westport, CT: Greenwood, 1949), pp. 33-34:A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die, and a new generation grows up that is familiar with it.as quoted in:• M. López Corredoira and C. Castro Perelman, ...


13

While Lorentz (before 1905) himself didn't directly address the question whether light speed is a universal limiting speed, there were many physicists before Einstein who argued that the speed of light cannot be reached, at least in the context of electrically charged particles. For instance, since 1881 the concept of electromagnetic mass was used, according ...


11

The idea, yes, Aryabhata speculated about something like that as early as c. 500 AD, Brahmagupta called it gurutvākarṣaṇ. So did Kepler, at about the same time as Ahmad Baba al Massufi (late 1500-s), and much less vaguely. Russo even ascribes the idea to Hipparchus (c.150 BC), although this is far fetched. Even the inverse square law for gravity predates ...


11

There are lots of different ways of stating the equivalence principle, and they're not all logically ... er ... equivalent to each other. Names that come up in this connection, from before Einstein, are Galileo and Eotvos. Experiments that test the equality of gravitational and inertial mass are called Eotvos experiments. Einstein's version of the ...


10

$ {\def\Target#1{\rlap{\smash{\label{#1}\phantom{\tag{#1}}}}}} {\def\BackUp{\raise{0.25em}{\Tiny{\boxed{\boldsymbol{\Uparrow} \hspace{-2px}}}}}} $tl;dr- It's unclear. The symbol $`` \hbar "$ itself wasn't anything new. Paul Dirac used it defining $\hbar \equiv \frac{h}{2 \pi}$ in a 1926 paper, but didn't explain the choice of the symbol. It might still be ...


9

There was an opposition. The reasons were mainly philosophical. The main thing which was hard to accept was "action at a distance" through the void space. For example Huygens did not accept this. It contradicted Descartes theory which was prevalent at that time. So the question had too be decided by observations and experiments, as it always happens in ...


9

Ancient Greeks painstakingly avoided negative numbers, although they could have come handy in astronomical calculations and number theory, among other places. Brahmagupta in Correctly Established Doctrine of Brahma (c. 630 AD) uses the language of "fortunes" and "debts", which suggests the merchant origin of the negative number concept, but that remains a ...


8

I suggest that the baseless suggestion offered in this question can best be answered by Einstein's own words about Newton, written in 1919. The background was the now-well-known eclipse expedition of 1919, in which the amount of deflection of light from stars close to the sun's limb had been observed during the eclipse. The results gave a probable ...


7

Hooke was not close (as far as we can judge from his surviving work) to what Newton accomplished. Yes, he conjectured the inverse square law. He understood correctly some simple qualitative features of the motion under this law. He probably performed some simple experiments suggesting these features. And he proposed to Newton to prove that the inverse square ...


7

Going by Wikipedia's definition, a physical constant is a number "generally believed to be both universal in nature and have constant value in time". The significance of these constants began to be recognized in the late 19th century, partly as a result of the standardization of the measurement system. But their modern prominence is due to Eddington's semi-...


7

It came to physics a bit earlier than quantum mechanics. The homomorphism $SU(2)\to SO(3)$ was discovered by Cayley (1843), Hamilton (1847), and Klein (1875) in their pure mathematical studies, and came to the attention of physicists through the theory of rigid body rotation (classical mechanics). It was Klein who brought it to the attention of physicists. ...


6

See Aristotle's Natural Philosophy. According to Aristotle, change in the natural world can be : [either] in accordance with the nature of the object — in which case the change is natural (phusei) or according to nature, or can happen in the face of a contrary disposition on the part of the nature of the entity — in which case the change is forced or ...


6

A side note first - when dealing with non-physicists, they will generally regard quantum mechanics as the end-all-be-all of physics, the coolest weirdest stuff. So, it is not surprising that your colleague focused on quantum mechanics and the rest was just engineering. So, lets look at your list first, then go on to some others of note that worked in the ...


6

Short answer, yes. The lengthiest quote of Landau's on religion that I know of comes from his article The Bourgeoisie and Modern Physics, which I doubt has been translated into English. Here is the Russian source, originaly published in Izvestia VCIK in 1935. My edited Google translation of the relevant passages is below: "However, one should not think ...


6

Newton proved that if the attraction obeys the inverse square law, then the force inside a uniformly charged sphere is zero. It follows from the description that you give that Cavendish used the converse statement. In fact this converse statement is true though I doubt that Cavendish had a proof of it in full generality. It is very common for physicists (...


5

In order to obtain a nonpulsating power source some early investigators used Wimshurst or similar static electricity generators, or batteries of many small storage cells. (The discovery of the electron, David L. Anderson)


5

'Did the Idea of Universal Gravitation predate Newton?' (The question went on to mention the books of Ahmed Baba.) I had a look to see whether Baba's work is available in any way online, but found nothing. Could the questioner point to any source, it would help discussion? Commentators who discuss early origins of gravitational ideas, perhaps as a ...


5

Another example of a "remarkable achievement of hand calculation" was in the field of mathematical astronomy. During 1758, Alexis Clairaut and his collaborators in Paris worked to refine Edmond Halley's prediction (published in 1705) of a return in about 1758 of the comet that now carries Halley's name. Halley's original prediction had been for 1758, ...


5

I've always liked logarithms because of their properties, and for some time I wondered who got the idea in the first place and how were the tables computed. It turns out logarithms were developed and computed simultaneously and independently by John Napier and Joost Bürgi. Both of them calculated huge logarithm tables by hand: Napier computed almost ten ...


5

Newtonian mechanics was resisted throughout its history, all the way until it was replaced by relativity and quantum mechanics. But the criticism did not so much concern the specifics of his laws of motion, there were few Aristotelians around, and, after all, they were pretty well confirmed by experiments, as their interpretations and "metaphysical" ...


5

“In Copenhagen again! The brothers Bohr fetched me at the pier, and now I’m established in Niels Bohr’s private palace. I had numerous conversations with the Bohrs and Mrs. Bohr, of course mostly political—but we even managed to talk an hour and a half on ‘the interpretation of quantum mechanics.’ I’m sure we were showing off, the both of us: giving an ...


5

Before Hamilton (1847) one should cite Euler (1771), Gauss (1819), Rodrigues (1840), and Cayley (1845). Detailed references in e.g. Pujol, J., Hamilton, Rodrigues, Gauss, quaternions, and rotations: a historical reassessment, Commun. Math. Anal. 13, No. 2, 1-14 (2012). ZBL1268.01010. Specifically, to four numbers $p,q,r,s$ with $pp+qq+rr+ss=u$, Euler (1771,...


5

Trigonometric functions became "mainstream" since the publication by Ptolemy (II AD) of trigonometric tables. To be sure he did not use our modern sine and cosine, but a single trigonometric function, the chord ($=2\sin(t/2)$). Modern definitions of sine and cosine were introduced by Indian mathematicians (Surya Siddhanta (V century AD), and reached Europe ...


5

The use of reduced mass in spectroscopy goes back to Bohr's planetary model of the atom. Nasri explains the context in his notes on quantum mechanics: "In 1912, Alfred Fowler showed that similar lines can be produced in a laboratory mixture of hydrogen and helium gas. Bohr noticed that they have the same spectrum of spectral lines as of hydrogen but with ...


4

Paul Krugman's research was caused by Isaac Azimov's Foundation novels. (For this answer, you have to accept economics as a science and you have to accept "caused scientists to do real research" in the sense of motivating them to do it.) From his interview, December 2008, on the Nobel website. (Yes, yes, I know, the Sveriges Riksbank Prize in Economic ...


4

The book Introduction to the Theory of Fourier's Series and Integrals by H. S. Carslaw answers your questions in the first chapter on the History of this subject. Many commonly held false beliefs are debunked in his first chapter, including the idea that Fourier failed to give a rigorous proof of convergence. Another common false belief is that Fourier ...


4

("How did Huygens derive the conservation law for of kinetic energy?") Huygens in 'The Motion of Colliding Bodies' (English translation) contributed ingenious reasoning, mathematics and thought-experiments based on physical assumptions. But this work was all about the collisions of a particular kind of body -- supposed and idealized at some distance away ...


4

The "mathematics" was a combination of experiments with falling bodies, imaginative thought experiments, common sense, and geometric reasoning. Part of it is explained in the book. Galileo found that $v^2$ at the time of impact is proportional to $h$. Torricelli argued that when two bodies are linked together and freely move, but only in a vertical plane, ...


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