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1500 questions
8
votes
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Where did the names positive and negative for the early voltaic piles come from?
The early voltaic pile has cells consisting of a [copper||electroltye||zinc] unit, and then another, so all of the zinc->copper junctions are metal-on-metal and all of the copper->zinc junctions are metal-on-electrolyte-on-metal, as neatly…
vy32
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8
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What is the origin of the term (non-)derogatory matrix?
A non-derogatory matrix $A$ is one, whose minimal polynomial $m(z)$ equals its characteristic polynomial $p(z)$, where we apply the convention $p(z) = det(zI-A)$, while a matrix is derogatory, if they do not coincide. I have certainly never felt…
thomashennecke
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Books on elliptic functions
In the end of his address to Annual Meeting of the Mathematical Association in 1933 titled "The marquis and the land agent: a tale of the 18th century", the Association president G. N. Watson says:
My final task is to express my gratitude to Prof.…
Alexandre Eremenko
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8
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When did computer pioneers realize that some problems are intrinsically hard?
In my theory computation class, I was told that early computer pioneers didn't realize that some problems are intrinsically hard—what we now call NP-hard problems. Instead, it took a while to realize that some problems could be solved with better…
vy32
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8
votes
1 answer
Why do some people represent vectors with overbars while others use underlines?
When I was originally introduced to vectors, I was told to write them with an arrow above the variable, like so: $$\vec{x}$$
As soon as I began taking vector-heavy classes, I found that those teachers dropped the arrow head:…
zaen
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8
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2 answers
What did G.H. Hardy teach Ramanujan?
Ramanujan didn't know modern mathematics. he lacked idea regarding analysis.
I found in Wikipedia-
Hardy tried his best to fill the gaps in Ramanujan's education and to
mentor him in the need for formal proofs to support his results,
without…
8
votes
1 answer
What were the not-so-convincing reasons for using the word "power" for power sets?
A footnote of Enderton's Elements of Set Theory (1977, page 4) for the definition of power set states that
the reasons for using the word "power" in this context are not very convincing, but the usage is now well established.
I wonder what the…
modnar
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What exactly was Lagrange's "grave mistake" with respect to rotating bodies under hydrostatic equilibrium?
A comment below What would be different about satellite orbits if Earth were prolate? Would we have Sun-synchronous and Molniya orbits? got me reading Wikipedia's Jacobi ellipsoid which begins:
Before Jacobi, the Maclaurin spheroid, which was…
uhoh
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8
votes
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Why is the existential quantifier symbol ∃ a backwards "E"?
Peano introduced a number of logical symbols still used today:
$∨$ (from Latin vel)
$∧$ (inverted $∨$)
$∃$
This inversion of Latin letters as symbols (and inversion of symbols to signify their 'opposite' operation) was followed by later…
iacob
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8
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Did Gosper or the Borweins first prove Ramanujans formula?
This is a copy of my question on MSE (https://math.stackexchange.com/questions/3372432) because this forum seems better suited for historical questions:
In 1985, Gosper used the not-yet-proven formula by Ramanujan
$$\frac{ 1 }{\pi } =…
L. Milla
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8
votes
2 answers
What is the history of staircase or =4 paradox?
The staircase 'paradox' has been discussed here and elsewhere a few times (search for staircase + paradox).
My question is whether this puzzle has been discussed in the academic literature or historically in mathematics. I can't find any reference…
buckner
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8
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1 answer
Historical origin of magnetic monopoles
There are two related historical questions that I'm trying to find answers to:
Who was the first to introduce the concept of magnetic monopoles?
Griffiths in his textbook Introduction to Electrodynamics refers to a model of magnetic dipole, formed…
Ivica Smolić
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8
votes
1 answer
Why do many names of technical and scientific subjects end with "ics"?
The names of many technical and scientific subjects, like mathematics, physics, statistics, etc., etc., end with letters "ics". What is meant by this, if anything? Was there any logic behind it or is it just random?
I have discussed this with some…
FAHDI GORSY
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8
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1 answer
What was the real need of divergence and curl operators?
As I'm advancing my study in Electromagnetism I'm getting introduced to more mathematical operators which are exclusively used in Electromagnetism and Fluid Dynamics only.
Let me try to explain myself through an example: Electric flux is defined as…
Knight wants Loong back
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7
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1 answer
What was the "libration of Pallas" that Gauss studied, when Pallas is not a moon of Jupiter?
This question is a request for general explanation of an astronomical phenomenon known as "Pallas libration", and isn't much about the details of Gauss's mathematical model of this libration. As is well known (see this post: Calculation of Gauss…
user2554
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