The historical development of physics concepts: who did what and when.

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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 ...
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2k views

How is the number of electrons in an atom found?

I was wondering, what type of experiments were held to identify the number of electrons in an atom? (For example, how do we say that carbon has 6 electrons and magnesium 12.) I would like someone to ...
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378 views

How do we know that the Law of Cooling is true?

According to James Stewart's Calculus book (exercise 14, page 609), Newton’s Law of Cooling states that the rate of cooling of an object is proportional to the temperature difference between the ...
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172 views

How did the concept of energy evolve with the years?

The concept of energy is quite common today but this was not the case before. As far as I know, even Newton, for example, didn't use this concept and Liebnitz just noticed that $mv^2$ was conserved ...
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65 views

When was Electromagnetically Induced Transparency first introduced?

The oldest paper I know regarding this topic was published in 1997 by Stephen E. Harris. But I am not sure if he is the first to introduce this idea. Could you tell me when and by who did introduce ...
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131 views

Physics involved in the DNA-structure discovery

In 1962 Francis Crick, James Dewey Watson and Maurice Hugh Frederick Wilkins won the Nobel Prize: For their discoveries concerning the molecular structure of nucleic acids and its significance for ...
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567 views

Before Einstein came up with General Relativity, were there serious reasons to doubt Newton's theory?

Before Einstein came up with General Relativity, was there any serious reason to doubt Newton's theory (and its various developments)? I only know about the discrepancy in Mercury's orbit, which may ...
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1answer
210 views

Engravings in “Wandering the Immeasurable” sculpture outside the CERN globe? [closed]

Does anyone have a PDF or a file that shows all of the engravings on the "Wandering the Immeasurable" sculpture by Gayle Hermick outside of the CERN globe of science and initiative?
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1answer
382 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 ...
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62 views

Have scientists always known that the Sun was not a fuel+air system?

Astronomy is far older than nuclear physics. So there was a long time in which fire was a reasonable explanation for the sun burning. Has any scientist figured out the sun cannot possibly be a normal ...
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130 views

How did special relativity change physicists views on the two prominent inverse square laws (ie Newton grav and Coulomb's law)?

On page 107 in Hartle's Gravity -- An introduction to Einstein's General Relativity, he says the following With the success of special relativity it became apparent that the Newtonian theory of ...
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107 views

What are the alternative explanations for the indirect evidence of gravitational waves? [duplicate]

Even though the consensus is that gravitational waves almost definitely exist, it has been well documented that there is no direct evidence. My question; what are the alternatives to gravitational ...
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111 views

What kind of thing did Lummer and Wien use as a 'black body'?

When I was reading about the experiments on the black body, I was wondering what such a black body would look like. When I google for the black body used during these experiments by Wien and Lummer, I ...
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2answers
181 views

What made Kepler think that orbits are not circular which came to be elliptical?

Kepler formulated his laws in a sort of time where human began to believe in heliocentric universe and telescope was not yet invented/ discovered. So what made Kepler think that orbits aren't circular?...
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3answers
244 views

Why do we need matrices in the Dirac equation?

Consider the following equation: \begin{equation} \nabla^2 - \frac{1}{c^2}\frac{\partial^2}{\partial t^2} = \left(A \partial_x + B \partial_y + C \partial_z + \frac{i}{c}D \partial_t\right)\left(A \...
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218 views

Gauss's Law of Electric Field how it actually works? & How Gauss derived it?

I want to know how Gauss derived his equation of Electric Field. Did he derive it from Coulomb's law? I don't think so. Please tell me some details about how this law works? inside a Gaussian ...
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132 views

How did steady-state universe deal with entropy?

Until the 1960's the general consensus was that the universe is infinite years old (steady-state). The second law of thermodynamics says that entropy always increases, so we'd expect that within a ...
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1answer
85 views

What was Einstein's 1923 Nature paper “The Theory of the Affine Field” about?

After his divorce with Mileva, Einstein published a paper in Nature entitled "The Theory of the Affine Field." Allegedly it confused renowned scientists. Why? What did the paper accomplish? What was ...
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285 views

How did Kepler infer three-dimensional positions from Tycho Brahe's data?

This has bugged me for some time. Tycho Brahe's data on planetary observations, presumably, consisted of the direction in which a planet was observed at a given date and time, but not the distance to ...
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1answer
135 views

How did Kepler formulate his second law from data?

It's amazing that Kepler derived his three laws emperically and then Newton rederived them from his own laws of motion. Its conceivable how Kepler derived the first and third laws, but the second law? ...
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55 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, ...
2
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1answer
189 views

How did Einstein arrive at the right hand side of his general relativity tensor equation?

It seems Einstein postulated the right hand side of his field equations… I see in books that tell the story of how he arrived at what to put on the right hand side of his tensor equations, the physics ...
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Why did Heaviside eliminate the magnetic potential from Maxwell's Equations?

Maxwell's original equations had magnetic potential, but Heaviside eliminated this variable. What was the reason for Heaviside's removal of the magnetic potential?
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363 views

What is reduced momentum in “A Dynamical Theory of the Electromagnetic Field” by James Clerk Maxwell?

I was reading Maxwell's paper titled [A Dynamical Theory of the Electromagnetic Field][1]. In part 2, section 3 ("Dynamical Illustration of Reduced Momentum"), Maxwell discusses a mechanical ...
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277 views

What's the symbol behind Einstein's head? [closed]

What's the symbol called that's behind and to the right of Einstein's head in this picture? Bonus if you can tell me what the whole formula is!
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86 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 ...
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519 views

How were the ratios of distances between planets and the Sun first calculated?

I was reading some literature and I found that long before the actual distances between other planets and Earth or distance between Sun and Earth were known, physicists had calculated the ratios ...
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If the field concept was invented by Faraday, then how did Newton interpret the $g$?

This is Newton's law of universal gravitation. $F=G\frac{m_1.m_2}{r^2}$ Gravitational field $g$ is derived from this formula $g=G\frac{m_1}{r^2}$ This is named gravitational "field" strength. If ...
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303 views

What theoretical predictions took the longest to be experimentally confirmed? [closed]

Looking forward to Einstein's general relativity centennial in 2015, I was thinking about how cool it would be if LIGO detects gravitational waves in 1916 (centennial of Einstein's "weak field" paper) ...
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5answers
637 views

On the foundations of quantum physics

Quantum physics has to be validated by experiments. But experiments are to be interpreted in the context of quantum physics. Isn'it like a snake biting its own tail? For example, using a scanning ...
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2answers
555 views

How did the operators come about?

This relates a little bit to my previous question (Experimentally, what categorizes a measurement as corresponding to a certain observable?), but it's different in a way and more historical. One of ...
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1answer
125 views

Einstein's space-time theory [closed]

I'm a high school student who never studied any relativity before, but I'm just wondering what was THE question that Einstein asked himself before going into this field. I knew he has done lots of ...
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3answers
3k views

How did Rutherford's gold foil disprove the plum pudding model?

What stops one of the two following scenarios from happening, consistent with the plum pudding model? The $\alpha$ particle, attracted by the electrons on the outer shell of the pudding, orbits ...
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120 views

History of QFT after 1973 [closed]

Where I can read about history of development quantum field theory after 1973? I'm interested in historical reviews, like as first chapter of the Weinberg's book.
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77 views

Maxwell's Inspiration to think about fields

I was looking at a Wikipedia article which had the following statement Atomists, notably James Clerk Maxwell and Ludwig Boltzmann, applied [...]. In modern literature Maxwell is often thought ...
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1answer
113 views

How did Planck use the concept of statistical entropy in trying to understand the meaning of his own law?

I was reading Introducing Quantum Theory: A graphic guide (by J.P.McEvoy & Oscar Zarate) and came across Planck's predicament of understanding his very own law that accurately explained the ...
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61 views

What is the history of the multichannel analyzer?

I'm doing a presentation over multichannel analyzers and one of the topics is "A Brief History of Multichannel Analyzers" and I am having great difficulty finding anything on the subject. I have done ...
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1answer
60 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 ...
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2answers
675 views

How exactly does applying the Equipartition Theorem to radiation leads to UV catastrophe?

I'm reading a book by George Gamow, "Thirty years that shook Physics" and have trouble understanding his way of describing the UV catastrophe. In a first part he points out that applying the ...
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56 views

Where do Newton's laws come from? [duplicate]

I have studied physics for about three years at university but after these years I still don't know how Newton derived his laws. I know that he tried to find the best model to describe the motions ...
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2answers
10k 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 ...
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4answers
584 views

Why is an electron negatively charged, and what is the difference between negative and positive charges?

Nobody has yet defined the actual meaning of a charge, or why a negative charge is different from a positive charge. Everybody knows that positive charge is due to protons and negative charge is due ...
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2answers
2k views

How did Newton establish his famous third law of motion?

For every action,there is equal and opposite reaction . This is the famous Newton's third law of motion. But how did he come to this conclusion? We can prove 2nd law using calculus. But how did Newton ...
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69 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 ...
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1answer
69 views

Why is the specific notation used for term symbols useful?

This has bugged me for a long time. Term symbols describe electronic states of atoms which have well-defined total electronic angular momentum $J$ as well as total spin and orbital angular momenta $...
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486 views

What made Einstein think that gravity was caused by the curvature of spacetime?

What observation/thought experiment led him to think this?
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2answers
5k views

How did Isaac Newton figure out how the law of gravity worked? [duplicate]

There are this and this similar Phys.SE questions, but I didn't find what I'm looking for, nor was the person's question specific enough. How did Newton figure out $$F=GMm/ r^2~?$$ What was his ...
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How did Newton discover the universal law of gravitation?

I am having trouble comprehending how anyone could come up with this formula: $$F = \frac{GMm}{d^2}.$$ Could someone walk me through this?
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136 views

Formulas for Haitz's law?

The Nobel Prize in Physics 2014 is for LED. There is a related Haitz's law: ...every decade, the cost per lumen (unit of useful light emitted) falls by a factor of 10, and the amount of light ...
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721 views

Who discovered that electromagnetic wave doesn't need a medium?

I have read that physicists in 19 century searching for the aether. They thought that light must have some medium to carry. When did they know that light and other electromagnetic wave doesn't need ...