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

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QM without complex numbers

I am trying to understand how complex numbers made their way into QM. Can we have a theory of the same physics without complex numbers? If so, is the theory using complex numbers easier?
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11answers
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How did Newton discover his second law?

I've always assumed/been told that Newton's 2nd law is an empirical law — it must be discovered by experiment. If this is the case, what experiments did Newton do to discover this? Is it related to ...
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2answers
3k views

History of interpretation of Newton's first law

Nowadays it seems to be popular among physics educators to present Newton's first law as a definition of inertial frames and/or a statement that such frames exist. This is clearly a modern overlay. ...
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2answers
399 views

Electromagnetic Momentum

My book says : The fact that electromagnetic radiation of energy carried momentum was known from classical theory and from the experiments of Nichols and Hull in 1903. This relation is also consistent ...
8
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3answers
606 views

What made us think that Earth moves around the Sun?

Trying to observe the night sky for a few weeks, the motion of the Sun and the stars pretty much fits into the Geocentric Theory i.e. All of them move around the Earth. What then, which particular ...
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6answers
2k views

Did Einstein prove $E=mc^2$ correctly? [closed]

In his book "Einstein's mistakes" H. C. Ohanian, the author, holds that Einstein delivered 7 proofs for $E=mc^2$ in his life that all were in some way incorrect. This despite the fact that correct ...
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1answer
966 views

Who (and Why) started the “electrons are negative, protons are positive” convention? [duplicate]

For some reason everyone labels electrons using a minus sign and protons using a positive sign, even though the opposite seems more intuitive: Who started the convention that electrons should be ...
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4answers
106 views

Newtonian physics vs Special relativity - what is the most “relative”?

This might be a question purely of words and the meaning of them but isn't Newtonian physics more "relative" than Einstein's Special relativity? Newtonian physics predicts that laws of momentum & ...
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3answers
2k views

What are the details around the origin of the string theory?

It is well-known even among the lay public (thanks to popular books) that string theory first arose in the field of strong interactions where certain scattering amplitudes had properties that could be ...
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1answer
1k views

What came first, Rice Crispy or “Snap,” “Crackle,” and “Pop”? [closed]

The fourth, fifth, and sixth derivatives of position are called "Snap" "Crackle" and "Pop". What came first, the rice crispy characters, or the physics units?
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3answers
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Why is the symplectic manifold version of Hamiltonian mechanics used in Newtonian mechanics?

Books such as Mathematical methods of classical mechanics describe an approach to classical (Newtonian/Galilean) mechanics where Hamiltonian mechanics turn into a theory of symplectic forms on ...
4
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1answer
2k views

Gabriele Veneziano, strong nuclear force and beta-function

Background to the question: From The History of String Theory: Gabriele Veneziano, a research fellow at CERN (a European particle accelerator lab) in 1968, observed a strange coincidence - many ...
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2answers
2k views

How did Halley calculate the distance to the Sun by measuring the transit of Venus?

What numbers did Halley, Cook, et al. have? What was the strategy by which they calculated the AU?
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2answers
967 views

How did Newton discover his third law of motion?

How did Newton discover his third law? Was it his original finding or was it a restatement of someone else's, like the first law coming from Galileo? What initiated the concept of what is now known as ...
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2answers
1k views

“Dear radioactive ladies and gentlemen” - Letter by Wolfgang Pauli

In 1930, Wolfgang Pauli wrote a letter to Lise Meitner for a convention in Tübingen, considering the problem of beta decay. Does anybody know, where to find the original letter online ?
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5answers
769 views

Regarding string theory: how to refute the argument “if it cannot be tested experimentally then it is not science”? [duplicate]

Possible Duplicate: What differs string theory from philosophy or religion? I find a lot of people disbelieve in string theory, saying that since it cannot be tested experimentally then it ...
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2answers
12k views

Lev Landau's “Theoretical Minimum”

The great russian physicist Lev Landau developed a famous entry exam to test his students. This "Theoretical Minimum" contained everything he considered elementary for a young theoretical physicist. ...
14
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6answers
2k views

Good book on the history of Quantum Mechanics?

Can anyone recommend a good book on the history of Quantum Mechanics, preferably one that is technical and not afraid to explain the maths (I did a degree in Physics many years ago) and also that ...
12
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3answers
2k views

Origin of Ladder Operator methods

Ladder operators are found in various contexts (such as calculating the spectra of the harmonic oscillator and angular momentum) in almost all introductory Quantum Mechanics textbooks. And every book ...
10
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3answers
285 views

On the theoretical aspects of the development of the first nuclear bombs

I've just read that 68 years ago Little Boy was dropped on Hiroshima, which made me wonder about some rather historical facts about the development of the first nuclear bombs; they seem to be several ...
15
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5answers
1k views

How was the formula for kinetic energy found, and who found it?

My questions mostly concern the history of physics. Who found the formula for kinetic energy $E_k =\frac{1}{2}mv^{2}$ and how was this formula actually discovered? I've recently watched Leonard ...
8
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2answers
438 views

What in Newton's three laws of motion is original and not a paraphrasing of his predecessors?

The three laws are: First law: The velocity of a body remains constant unless the body is acted upon by an external force. Second law: The acceleration a of a body is parallel[disambiguation needed ...
6
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5answers
379 views

Infinities in Newtons law of gravity (for point particles)

Newtons law of gravity for two particles of mass $m_1$ and $m_2$ is: $G\frac{m_1.m_2}{r^2}$. Supposing that the particles are point particles then gravitional attraction will bring them closer ...
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1answer
134 views

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?
5
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1answer
570 views

When and how were relative distances to the planets first measured?

I understand that the absolute distance to a planet can be measured using earth-baseline (e.g., diurnal) parallax, and that the first reasonably accurate such measurement was made for Mars by Cassini ...
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2answers
5k views

Electric field of a negative charge

How was it discovered that the electric field of a negative charge points towards the charge itself? Is it true? (Courtesy of wikipedia)
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2answers
109 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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4answers
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Historically, how do we know that Earth moves around Sun? And it does so in an elliptical orbit?

I know the basics of solar system like how Earth moves around Sun, and that we have so many planets, elliptical orbit of earth, and how far is sun from earth etc etc. I want to take a step back and ...
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3answers
1k views

Work of Marie Curie?

I've been reading about the work of Marie Curie recently after a friend filled me in on what she did (never having had much of an idea previously) and it's all very interesting. What I can't ...
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3answers
198 views

How was Newton able to guess that gravitational force is inversely proportional to distance squared?

This question is puzzling me since I learnt about the gravitation law in school. Why did Newton guess/assume that gravitational force is inversely proportional to the square of distance? Did he ...
0
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2answers
814 views

What were the intention/conclusions for Michelson-Morley experiment?

Which of the following were the intentions of M&M? to disprove the existence of aether. to show that the aether has no effect on matter and energy and therefore is as good as non-existent. ...
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3answers
686 views

Accidental, unplanned breakthroughs in physics [closed]

There is possibly some idioms or saying like this, ``If you try too hard for something, you will never get it. If you do not aim for something, it may fall on you accidentally, not as you originally ...
39
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1answer
2k views

What happened to David John Candlin?

This is an ultra-soft question about relatively recent history. While reading some of Mandelstam's papers, I noticed that he cites David John Candlin consistenly whenever he does anything with ...
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8answers
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Myths in the history of Physics

As an example of such a historical myth that we all learned, there is the story that in his confrontation with Cardinal Bellarmine in 1632, Galileo had all the evidence on his side, won the ...
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5answers
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What problems with Electromagnetism led Einstein to the Special Theory of Relativity?

I have often heard it said that several problems in the theory of electromagnetism as described by Maxwell's equations led Einstein to his theory of Special Relativity. What exactly were these ...
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4answers
2k views

History of Electromagnetic Field Tensor

I'm curious to learn how people discovered that electric and magnetic fields could be nicely put into one simple tensor. It's clear that the tensor provides many beautiful simplifications to the ...
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2answers
248 views

Examples of “pseudo quantum effects” in history of physics

Are there any examples in the history of physics where a phenomenon was considered by the physics community to be not explainable by classical physics and needed a quantum explanation whereas some ...
13
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2answers
2k views

Einstein's box - unclear about Bohr's retort

I was reading a book on the history of Quantum Mechanics and I got intrigued by the gendankenexperiment proposed by Einstein to Bohr at the 6th Solvay conference in 1930. For context, the thought ...
5
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1answer
344 views

Historical and philosophical reflexions about the concept of energy? [closed]

Perhaps you know the books: Concepts of Mass in Contemporary Physics and Philosophy Concepts of Force: A Study in the Foundations of Dynamics by Max Jammer, which discusses mass and force from a ...
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4answers
637 views

Newton's first law: is his concept of (force of ) inertia still useful and used?

The force of inertia is the property common to all bodies that remain in their state, either at rest or in motion, unless some external cause is introduced to make them alter this state. That ...
5
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0answers
111 views

Victorian cosmology after the second law of thermodynamics but before relativity?

In the 19th century, most astronomers adopted an island universe model, in which our galaxy was the only object in an infinite space. They didn't know that the "spiral nebulae" were other galaxies. ...
3
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2answers
226 views

How did ancient physicists around 500 BC decide that the earth is spherical?

One of the standard stories that is given for this (and is mentioned in Aristotle) is that the hull of a ship disappears first as it sails towards the horizon on a calm sunny day. Is this a myth, or ...
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5answers
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How was Avogadro's number first determined?

I read on Wikipedia how the numerical value of Avogadro's number can be found by doing an experiment, provided you have the numerical value of Faraday's constant; but it seems to me that Faraday's ...
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3answers
3k views

Did Hilbert publish general relativity field equation before Einstein?

Did Hilbert publish general relativity field equation before Einstein?
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2answers
622 views

How did pre-Copernican astronomers accurately predict planetary position?

Copernican elements (circular orbital elements) are not very accurate. But Copernicus simplified our understanding a great deal by placing the Sun at the center of the system. Im astonished by the ...
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2answers
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Is there a good Modern English translation of Newton's “Philosophiæ Naturalis Principia Mathematica” available for free viewing or download?

I have found several nice versions available for purchase, but all of the free ones are either Latin, old English, or pixellated. I searched google and was only able to locate the free ones linked to ...
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1answer
845 views

The origin of femto, atto and zepto SI prefixes

Do you know why the SI prefixes: femto, atto, zepto have been accepted by Scientific Community, if this triad of metric units, is neither greek nor latin?
5
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4answers
659 views

How did “no prior geometry” father 50 years of confusion?

I've come across this quote attributed to Misner, Thorne & Wheeler from their book, Gravitation: Mathematics was not sufficiently refined in 1917 to cleave apart the demands for "no prior ...
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1answer
750 views

How did Copernicus establish the relative distance to the superior planets?

I understand that the relative distances to the planets had been calculated using various methods since ancient times, and, in particular, that the assumptions of the Copernican model of the Solar ...
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3answers
614 views

Why didn't Newton just propose the 2nd Law and leave it at that?

Why didn't Newton just propose the 2nd Law ($F=\dot{p}$) and leave it at that? The 2nd Law implicitly contains the first, doesn't it? If so, it seems he wasn't following his own Rule #1 of Book 3 of ...