33 votes

Timeline of measurements of the electron's charge

If anyone's still reading this thread, here's a few more data points that appear to back Feynmann's interpretation. Erik Bäcklin, Nature vol 123, no. 3098, p. 409 (1929): $1.59875 \cdot 10^{-19} \pm ...
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  • 431
21 votes

Timeline of measurements of the electron's charge

The 16th (1995) edition of Kaye and Laby includes the following progression of the accepted values for the charge of an electron. The first value "is essentially Milikan's oil drop value" and the ...
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  • 1,144
20 votes

Is Millikan's famous oil drop experiment a fraud?

Note: I present here some information defending Millikan, but please note that I do not necessarily agree with the article it came from. From the feature article "In Defense of Robert Andrews ...
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19 votes
Accepted

Did the pioneers of nuclear physics and radioactivity eventually get sick from their experiments?

Marie Curie is probably the most famous example of a person who died of the effects of radiation (handling a lot of radium mostly - for the discovery of which she won the Nobel prize in Chemistry). ...
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  • 758
16 votes
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When did it become possible to predict the time and place of solar eclipses?

The principle was known long ago, to the Babylonians and Hellenistic Greeks but the accuracy of prediction depends on the detail of the Lunar motion (the motion of the Sun is relatively simple). ...
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16 votes
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When & how was it known that our Sun is the same thing as the night time stars?

As quoted from this article: Many people's work was needed to prove that the Sun is a star. The first person we know of to suggest that the Sun is a star up close (or, conversely, that stars are ...
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  • 1,516
12 votes
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Did the Digges Telescope actually exist?

It all depends on your definition of a telescope. Digges absolutely built some sort of device that was capable of magnifying objects. It seems that is agreed upon. But the divide is really about ...
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  • 8,082
12 votes
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Discovery of Earth's magnetic field

As it turns out, it was already known by some philosophers from the 1200s that certain types of rocks naturally tend to rotate to point north. However, they had no idea why: For instance, it was ...
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  • 3,682
11 votes
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What were the early empirical tests of Einstein's mass-energy equivalence $E=mc^2$?

Let me clarify first that there are deep conceptual issues with what $E=mc^2$ means, and what it means to verify it. That energy contributes to inertial mass was known before Einstein. In 1900 ...
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11 votes
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Did Hooke's law come from experiments, or was it mathematically derived from Newtonian mechanics?

Newtonian mechanics was not yet in place when Hooke published his De Potentia Restitutiva (On Restoring Force) in 1678, Newton's Principia only came out in 1687. Hooke inferred the law from ...
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11 votes

How did J. J. Thomson establish the particle nature of the electron?

The idea that matter was made up of "primordial" particles, and currents in metals consisted of them was well established by then. Stoney suggested the name "electron" in 1891, and Lorentz's theory of ...
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10 votes
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When was it first realized that sound travels with finite speed?

The question is delicate because of the phrasing that assumes empirical approach, which did not emerge until 17th century. And the notion of "speed" as applied to sound presupposes the concept of wave ...
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10 votes
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How did Young perform his double slit experiment?

Young's original setup demonstrating interference of light was not double slit but sunbeam splitting with a single thin card. He presented a paper On the theory of Light and Color to the Royal Society ...
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10 votes

Did the pioneers of nuclear physics and radioactivity eventually get sick from their experiments?

It's hard to quantify the negative effects of radiation. In 1978, a Russian scientist was struck by a particle accelerator beam during routine experimentation. He saw a flash "brighter than a thousand ...
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  • 101
9 votes
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Did Galileo perform an experiment at the Leaning Tower of Pisa?

See the detailed discussion on : Stillman Drake, Galileo at work, (1978), page 414–16. In 1641 Galileo’s successor on the chair of mathematics at Pisa, Vincenzo Renieri, experimented with ...
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9 votes
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Could scientists of Newton's time have explored the limits of his laws of motion?

At the time of Newton, the scientists could NOT detect any deviation of the Newton's laws from reality. As we know now, the only visible effect of this deviation in the Solar system is the anomalous ...
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9 votes

How did Stern or Gerlach, of Stern-Gerlach experiment, create individual silver atoms? How were they accelerated?

Atomic spectroscopy was very advanced 100 years ago (1920s) and we must appreciate their intelligence. If a metal like silver is being heated to the extent of boiling in high vacuum, all you get is ...
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8 votes
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Discovery of magnetic field reversals?

Cox et al. 1964 gives a good account on the different steps of how this discovery was made. The most important first step was to acknowledge the fact that some rocks (namely magmatic rocks) acquired a ...
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  • 1,340
8 votes

Were there serious attempts to model the photoelectric effect classically?

"Serious" in the OP sense is probably too high a bar. In 1900-s the situation was very much in flux as to what classical physics could and could not explain. Even Planck's and Einstein's ...
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8 votes

What was the longest delay between prediction and confirmation of a theory?

There is inherent vagueness in dating "predictions" and "confirmations" in many cases. For instance, who predicted heliocentrism? Copernicus, Kepler, Newton, perhaps Aristarchus? When was it confirmed?...
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8 votes

What did it historically mean in physics for something to "exist"?

To not be measured is not to have any behavior. No dynamic is induced on any other system in the universe by this object (Rosen 1978). Objects without behavior do not exist. Their behavior is that ...
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8 votes

Does anyone know of any examples of the Magnus effect in a real battle?

I am afraid nobody noticed it, because nobody could have noticed it. A deviation is only a deviation when one has something that it is a deviation from. To "notice" the Magnus effect one has to ...
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8 votes
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Significance of Higgs model used in Glashow-Salam-Weinberg theory

This is precisely why this question belongs to HSM.SE with both feet! Your vision of what happened is deeply misleading, possibly requiring time travel. Recall the GWS 79 prize citation: "for ...
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8 votes

Have there been instances in physics where different scientists have interpreted the same data differently?

The comments correctly say that this happens all the time. For a recent example, you can see my answer to: Can a highly-cited published paper have this type of error? I will explain here some details ...
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7 votes

Did the pioneers of nuclear physics and radioactivity eventually get sick from their experiments?

The Demon Core, a subcritical mass of plutonium, went critical during two distinct incidents in 1945 and 1946. Both times, scientists were killed due to exposition to radiation. During the second ...
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  • 171
7 votes

How did people react to the realization that Aristotle's ideas had gone without question for way too long?

I would not call this "horrendous mistake", and I disagree with Conifold's statement that the reason was canonization by the Catholic Church. It is easier to disprove Conifold's statement, so let me ...
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7 votes

speed of light measurement

This image: is the most explicit one I've found for the experimental arrangement. Here's another that is more schematic, but illustrates the basic idea: Now on to your specific questions. The light ...
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7 votes

What was the longest delay between prediction and confirmation of a theory?

I think Guido makes a good point in a comment that the analogue in math would be proving an old conjecture, and for this there are many examples that were settled after over 100 years. Besides Fermat'...
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  • 4,014
7 votes

Who was first to observe or detect photons in the double slit experiment, and how did they do that?

To the contrary, Young's point was to disprove the then dominant Newton's corpuscular theory of light by demonstrating light's wave properties, see How did Young perform his double slit experiment? ...
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