# All Questions

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19 views

### How did Einstein make the connection between the special and general relativity?

The world famous thought experiments about chasing light beams and accelerating elevators gave Einstein insight into the Nature of spacetime. The chasing lightray experiment hinted at the ...
40 views

### On what grounds did Crick founded the central dogma of biology?

In 1957 Crick installed the central dogma of biology: The Central Dogma. This states that once "information" has passed into protein it cannot get out again. In more detail, the transfer of ...
316 views

### $2^{11} - 1$ and the mystery of Huldaricus Regius

While researching on Mersenne numbers, I often stumble upon statements of this nature (it is not verbatim): Huldaricus Regius in 1536 proved that $2^{11}-1$ is not prime, providing a factorisation ...
101 views

### How come that the “heroes” in physics are gone?

I'm not sure if this question can be answered objectively but I still ask. Once upon a time there were people like Galileo, Newton, Einstein, Feynman, Curie, Tesla, Dirac, Schrödinger, maybe Chopra, ...
35 views

### On the origin of “sandwiches” in quantum mechanics

The term "sandwich" and the verb "to sandwich" appear pretty common but informally in quantum mechanics. Generally when describing some kind of inner product of the form: \langle ...
158 views

### Why is periodic motion always represented as a sine function

Why was periodic motion started to be represented as a sine function at the beginning? Is it because it is perhaps the simplest periodic function? Is there certainly any reason behind this ...
45 views

### Was Einstein's “Maschinchen” a predecessor of the photomultiplier tube?

Einstein once got involved in true experimental physics. That is, he designed his little machine (Maschinchen, in German, a word that makes me laugh; Einstein's Maschinchen...) to detect small ...
34 views

### How was the first calculation of the g-factor done?

Dirac said the magnetic g-factor (a measure of the electron's wiggling in a magnetic field) is exactly 2. Quantum field theory introduced a g-factor that diverged a bit from 2. It needs an increasing ...
58 views
+100

### Earliest numeric value for helium D3 line

In late 1868, Norman Lockyer discovered the existence of the D3 emission line of helium in the solar spectrum. What was the earliest published example of a numeric value for the wavelength of this ...
65 views

### What was the attitude towards atoms around the turn of the nineteenth century?

Einstein invented, on his own, a statistical mechanics, presupposing the existence of atoms. I can't imagine he was unaware of the shortly-before-invented statistical approach by Boltzmann and others, ...
54 views

### What was the poetic duel Einstein had with Lilly Rona about?

Felix Ehrenhaft was married to Lilly Rona. Einstein and Ehrenhaft regularly met and discussed about magnetic poles or fractional charges. Einstein didn't agree and used his authority to keep Ehrenhaft ...
48 views

### Why was André Weil in Finland?

E.g. here it says: During the Second World War André Weil was first imprisoned in Finland, accused of spying, then after being returned to France he was put into Rouen prison convicted of being a ...
33 views

### Why are pilot waves in quantum mechanics said to be Faraday waves?

De Broglie proposed a pilot wave in connection with quantum mechanics. He was more or less forced to abandon this wave in favor of the Copenhagen view. Bohm furthered his approach in the fifties but ...
59 views

### Did tobacco smoke confound the results of an experiment by entering a reaction with the subject of study?

I dimly remember watching a popular sciencie movie that mentioned an experiment conducted by a pair of great physisicists (Einstein was one of them, unless my memory is playing tricks on me) that had ...
250 views

### Whatever happened to quaternions?

Quaternions were made up by Hamilton. They are an extension of complex numbers. It is said that he first introduced "3d tertions". He was thinking what the relation between i and j had to be ...
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### What kind of mathematics had Max Ernst in mind?

Max Ernst was a painter belonging to the Dadaistic movement. One of his paintings shows Euclid in a somewhat, well, let's say Dadaistic fashion (although fashion and Dadaism don't go along well). We ...
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### What were Gregor Mendel's and Darwin's views on evolution?

Mendel's laws (like the laws of segregation or inheritance) became known to a wider publis decades after he discovered these laws. He assumed trait particles in operation that were responible for his ...
45 views

### Where there scientists before Einstein who viewed space(time) as being elastic?

Einstein was the first who saw spacetime as a mallable substance to be malled with mass. As far as I know there were no people who suggested such a view of spacetime before him. But I could be wrong. ...
63 views

### What is the largest academic genealogy tree that we know of?

Many famous scientists are connected by their doctorate advisor-student relations. I wonder if we know which is the largest continuous chain of famous researchers. I have checked pages like ...
63 views

I read: Suddenly – boink! -an apple hits him on the head. “Aha!” he shouts, or perhaps, “Eureka!” In a flash he understands that the very same force that brought the apple crashing toward the ground ...
74 views

### What's the true story about Galilei?

Scientists use the story of Galilei to advocate the glory of the sciences and the stupidity of the church. This is obvious from ironic remarks made by them that criticize its attitude. In fact, this ...
79 views

### When were equivalence classes formalized?

Neither wikipedia or the first few pages of Google are showing me much about the history of the development of equivalence classes. When was this notion first formalized? Footnote: I originally asked ...
62 views

### Which modern sciences/technologies were contingent on the Copernican Revolution, & which could have developed even while believing in geocentrism? [closed]

Suppose that, for whatever reason, neither Copernicus nor anyone else had discovered the heliocentric model, and cosmology remained stuck in the geocentric model. ("For whatever reason" ...
45 views

### Help understanding Egyptian circle

I was reading this Wikipedia page searching for the Egyptian area of circle and there is a following picture there: Trying to understand what is meant by this since it is under the "Area" ...
60 views

### When were brains seen as computers for the first time?

Let me state firstly that I don't think that the nervous system is a computer. Not down up, nor top down. On top of that, brains cannot truly be separated from the body. I am curious still. Who were ...
102 views

### Aziz of Complex Analysis

Does anyone know about Prof. Abdul Aziz on whose name Aziz's theorem is named? Aziz's theorem is a theorem about the location of zeros of polynomials.
166 views

### Why didn't the phase space formulation of Quantum Mechanics get the upper hand?

At university I learned quantum mechanics in or position or momentum variables. Later (in fact on this site), I learned about the phase space formulation in which both are used at the same time. The ...
40 views

### How did Eratosthenes know the difference between two cities? [duplicate]

First, be familiar with how Eratosthenes first got an estimation of the earth's circumference. My questions is fairly simple: how did they know the distance between two cities back in the days? ...
51 views

### When was the bitter controversy between Ehrenhaft and Millikan ended?

Felix Ehrenhaft made a claim that he saw electric charges smaller than an electron. In that respect he was ahead of his time. Far ahead, as quarks haven't been detected yet directly. His measurements ...
171 views

### Why wasn't madam Wu awarded a Nobel Prize?

In landmark experiment in physics Wu discovered that Nature has a preference for right or left. It were the proposers of this asymmetry though who ran away with the the Nobel prize. Madam Wu wasn't ...
104 views

### Explanation of the main points in Gauss's resultant calculus

After he read Mobius's 1827 treatise on the "barycentric calculus" (according to Gauss's own testimony, he read this treatise only in 1843), Gauss wrote down several unpublished notes on ...
137 views

### How did the ancient Indian sages know speed of light?

There is a shloka in the Rig Veda, which mentions the value of speed of light. तथा च स्मर्यते योजनानां सहस्त्रं द्वे द्वे शते द्वे च योजने एकेन निमिषार्धे- न क्रममाण नमोऽस्तुते- ॥ (Devnagari script) ...
41 views

### Can we find clues in the archives of science why physicists chose to say goodbye to determinism after the introduction of QM?

It is a well-known fact that quantum mechanics states that ďeterminism does not exist on a fundamental level. On that level, Nature is inherently probabilistic. That is, that is how the theory is ...
130 views

### What did Fourier mean by stating that every function can be decomposed into sine and cosine functions?

Fourier stated that every function can be decomposed into sine and cosine functions. Was he referring to periodic functions only? To a certain class only? I ask, because it seems clear (at least to me)...
70 views

### Was Fourier inspired by Ptolemy?

Ptolemy invented a system to describe the periodic motion of the planets by epicycles. Fourier did something similar for periodic motion in mechanics. Every such motion can be thought of as ...
70 views

### Was Becquerel's discovery of radioactivity inspired by his father?

Becquerel was awarded the Nobel prize for his discovery of radioactivity. He was researching phosphoresence and decided one day to place the stuff he used in a drawer to keep it out of the sun. He put ...
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### Did Poincaré argue against defining terms before you proceed?

Can the following point of view be traced back to a particular publication by Poincaré? In Section 3.1 of Gravitation, by Misner, Thorne and Wheeler, the authors write: Here and elsewhere in science, ...
4k views

### What are examples of serendipity in the history of the sciences and math?

Cosmic microwave background radiation was discovered after Penzias & Wilson couldn't get rid of the noise generated by their horn. In fact, the noise was their discovery. The strings in string ...
57 views

### Is there any literature or articles which expand more on Einstein's thoughts about Dostoyevsky's novels?

It is a well known fact that he admired Dostoyevsky even more than scientists. I'm looking for things like, Einstein's opinions about his religious discourse? What did he think of his bold statements ...
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### Did the sages that composed the earliest version of Surya Siddhanta know for certain that the Sun is not a planet and the Moon not a star?

The Vedic jyotisha acquaints us with the navgraha which includes 'Surya' (by which term the Sun is meant in India today) & 'Chandra'(a modern Indian term meaning the Moon) while it excludes the ...
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### What was Higgs' attitude towards his own mechanism?

Higgs invented a mechanism to endow quarks and leptons an W- and Z-particles with mass. If a particle is massless though then how can it be slowed down by interacting with another particle? Maybe the ...
86 views

### How the random numbers were generated which were used during world war 2(ww2)?

I know One-time-pad were used during ww2 and, I want to know how the random numbers were generated.
36 views

### Did proponents of classical and statistical thermodynamics get along well with each other?

Proponents of classical thermodynamics believed the subject matter to be continuous, while the statistical thermodynamics proponents' subject matter was made up of atoms and variations of collectives ...
60 views

### How does Copernicus explain the discrepancy from “On the Revolutions of the Heavenly Spheres” Book 5. chapter 16

In "On the Revolutions of the Heavenly Spheres" Book 5. chapter 16, Copernicus appears to acknowledge a discrepancy between the old Ptolemy observation and the model. Here is a Google ...
102 views

### What does the Fourier transform have to do with heat?

For example the current version of the Fourier analysis article on Wikipedia says the study is: […] named after Joseph Fourier, who showed that representing a function as a sum of trigonometric ...
208 views

### Does the practice of viewing modern mathematics as the necessary direction in which ancient mathematics must have evolved have a name?

I have noticed a tendency among some historians and scholars of mathematics to regard the mathematics of antiquity as a less developed version of modern mathematics. This view reminds me of the belief ...
94 views

### Collatz letter to Professor Mays

According to a translation of the letter of Collatz to Professor Mays in 1980, Collatz mentions that he hasn't figured out whether the number n = 80 resulted in a cycle or not, concerning the collatz ...
100 views

### To what level did mathematics develop in the western world without Hindu-Arabic numbers?

To what level did mathematics develop in the western world without Hindu-Arabic numbers? A related question is how were calculations performed without Hindu-Arabic numbers? (I don't know if I should ...