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Cavendish Laboratories Photo, 1939
So this photo of the Cavendish Laboratory is from 1939, and I was wondering if anyone knew any more about who was in the photo. (Click to enlarge)
From notes I've been given, I believe the front row is:
DE Lea?; Unknown; ME Oliphant; Norman…
Savara
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Why was delta ($\Delta$) chosen to represent change of a quantity?
In many fields, it's common for $\Delta$ (the Greek letter delta) to represent a change or difference. Math uses it, physics uses it, engineering uses it, etc.
Why was $\Delta$ chosen for this?
I realize that "difference" starts with "d", but I'm…
Joe
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Why was the Tertiary period dropped but the Quaternary retained?
The terms Primary, Secondary, Tertiary, and Quaternary were coined by early geologists as they tried to make sense of the rocks around them. As they began to understand what was going on, they found "Primary" and "Secondary" were unhelpful terms,…
winwaed
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What motivated Gauss' quadratic sums?
The proofs of quadratic reciprocity based on quadratic Gaussian sums involve sums of the form
$$\sum_{k=1}^{p-1}\left(\frac k p \right)\zeta^{ak}$$
Where $\left(\frac k p \right)$ is a Legendre symbol and $\zeta$ is a $p$-th root of unity. Where…
Jack M
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When and how was UV radiation found to be dangerous to human skin?
It is pretty common knowledge nowadays that prolonged exposure to solar ultraviolet radiation is dangerous to human skin, potentially resulting in cancers such as melanoma and photoaging.
A bit of background from the Skin Cancer Foundation's webpage…
user22
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1 answer
When did humans realize that sex leads to pregnancy?
When did primates, protohumans, or humans make the connection between sexual activity and pregnancy?
I notice that many ancient statues depict pregnancy or penises, this may (tenuously) suggest that the connection was known at the time that…
dotancohen
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Why did India miss the Great Revolution in Maths and Science?
UPDATE: I've updated the title of the question from Why did India lag behind in discovering Maths and Science? to Why did India miss the Great Revolution in Maths and Science? after some of the answers and comments provided.
NOTE: This question lies…
shivams
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How and where was the notion of a primitive root formulated before Gauss?
Gauss credits Euler (and I think some others) with having known of the existence of primitive roots. How did these predecessors of Gauss formulate the notion of a primitive root without a concept of congruence? In what works, and in what context? In…
Jack M
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How were vector calculus nabla ∇ identities first derived?
(Math Stack Exchange suggested that the same question I posted there be migrated here; The one at Math Stack Exchange was thus deleted. The recommendation message of migration can be found here, though the page is now deleted.)
Whenever students are…
Secret
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What were the initial applications of finite fields?
Finite fields, I believe, were introduced by Galois in his paper "Sur la théorie des nombres", found on page 398 of his Oeuvres. In this paper Galois introduces the idea of taking a polynomial equation $f(x)=0$ having no solution modulo some prime,…
Jack M
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2 answers
Einstein's assistants
Some previous questions on Einstein bring the following question: is a complete (or incomplete) list of Einstein assistants available somewhere?
A quick search on the Internet brings several familiar names, but no list.
I know many of them,
but I…
Alexandre Eremenko
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11 answers
Was Aristotle really wrong about gravity?
When I was in 9th grade, I learned that Aristotle was responsible for holding back physics for centuries because he said that heavier objects fall faster than lighter objects. Finally, in the 16th century Galileo disproved this theory by dropping…
Craig Feinstein
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Why did 92% of cases of simultaneous discovery in the 17th century end in dispute?
I read on
http://en.wikipedia.org/wiki/Academic_publishing :
One of the earliest research journals is the Philosophical
Transactions of the Royal Society, created in the 17th century. At
that time, the act of publishing academic inquiry was…
Franck Dernoncourt
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Was Euler's theorem in differential geometry motivated by matrices and eigenvalues?
I am teaching a class on elementary differential geometry and I would like to know, for myself and for my students, something more about the history of Euler Theorem and Euler equation: the curvature of a normal section is determined by the…
Giuseppe
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How much of a conceptual leap forward was 'Systema Naturae'?
Binomial nomenclature, and with it modern taxonomy, is said to have appeared with Carl Linnaeus' Systema Naturae (1758, the year during which the 10th edition of the book was published, being Year 0 of nomenclature as far as the ICZN is…
plannapus
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