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Correct citation of “The method of successive approximation for functional equations” by L. Kantorovich, Leningrad, 1939?

The citation we get from http://projecteuclid.org/journals/acta-mathematica/volume-71/issue-none/The-method-of-successive-approximation-for-functional-equations/10.1007/BF02547750.full says ...
AlMa1r's user avatar
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History of functions of bounded variation

I have read that Jordan first defined the concept of variation and studied functions of bounded variation, in his 1881 publication Sur la Serie de Fourier, as referenced here: https://en.wikipedia.org/...
Addem's user avatar
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What were people looking for when they started to study bounded linear functionals?

Very briefly, my understanding of the initial motivations for studying $L^p$ spaces included interest in the $\ell_2$ space, due to relationships with quadratic forms that arose from searching for ...
Addem's user avatar
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1 answer
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How did Schrödinger do quantum mechanics with wave functions?

On my way to learn about the very beginning of quantum mechanics and its different formulations, starting with Heisenberg infinite matrices and Schrödinger's wave functions, I can really not find till ...
user19358's user avatar
4 votes
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Is there existing footage of Stanislaw Mazur giving Per Enflo a live goose for solving the approximation problem?

There is a famous incident in the history of mathematics involving the mathematician Per Enflo being awarded a live goose by Stanislaw Mazur for solving problem 153 in the Scottish Book by ...
James E Hanson's user avatar
2 votes
1 answer
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$l^p$ space definition

Usually, when studying the applications and results of a theory, it becomes clear why it was interesting to define it in a certain way. However, I'm currently beginning my studies in functional ...
ends7's user avatar
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3 votes
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Can not find reference for "uniform convexity implies existence of unique conjugate" mentioned by Pettis

In A proof that every uniformly convex space is reflexive in footnote 3 (available at that link without a paywall), author Billy Pettis mentions that the first half of Lemma 1 in that paper "was ...
ViktorStein's user avatar
8 votes
1 answer
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Banach chicken story

I think in undergrad functional analysis we were told an anecdote that at Stefan Banach's university in Warsaw they maintained a list of open problems which had material prizes attached to them ...
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When and how did signal processing reach the core of functional analysis?

Functional analysis and signal processing have a strong bond and I am trying to understand how and when it all started. Technically, signal processing is heavily based on Fourier analysis, which helps ...
SPARSE's user avatar
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3 votes
1 answer
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Who introduced recurrence relations and sequences?

I want to know who was the first scholar or mathematician to have introduced and formulate the concept of recurrence relations, that is finding a function given the how one value of a sequence is ...
Don Al's user avatar
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2 votes
1 answer
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Who proved Banach fixed point theorem in abstract metric spaces for the first time?

If one studies the paper written by Banach in which he first proved his fixed point theorem one would find that he did not prove the theorem for abstract complete metric spaces. He proved it for the ...
Aman Sharma's user avatar
4 votes
1 answer
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Original mathematical foundation of Dirac's function

In which paper/book (most likely) by either Sobolev or Schwartz is the Dirac function properly and explicitly substantiated as a functional (tempered distribution), preferably quoting Dirac's name? I ...
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Origins of Stone duality

My question is a mix of mathematical and historical, if you consider my question will be better answered in the mathematics community, please tell me. I want to know the historical roots of Stone's ...
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Who extended the Banach fixed point theorem from the context of normed spaces to the context of metric spaces?

It is well known that Banach's fixed-point theorem was initially conceived as a fixed-point theorem for applications defined in normed spaces (see [1]). This theorem was conceived in 1922 by Stefan ...
MathOverview's user avatar
5 votes
1 answer
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Who first proved the "acute angle principle" in fixed point theory?

After getting such an informative response on my first question, I have another theorem discussed in our lecture who´s origin I am interested in (sometimes called the "acute angle principle"): ...
ViktorStein's user avatar
3 votes
1 answer
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Who first proved that the spectrum of an operator is contained in the closure of its numerical range?

We have recently proven in our functional analysis II lecture that the spectrum of an operator is contained in the closure of its numerical range. On the German wikipedia page for the numerical radius ...
ViktorStein's user avatar
3 votes
0 answers
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Asymptotically Periodic Potentials

Who came up with the idea of solving elliptic equations with periodic potentials and from there solving elliptic equations with asymptotically periodic potentials? I heard it was Pierre Louis Lions, ...
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3 votes
1 answer
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Who proved the monotone convergence theorem for the Lebesgue integral?

The theorem often be called Lebesgue's MCT or Levi's theorem. Who did originally prove it or what is the contribution of Lebesgue and Levi respectively?
MiGang's user avatar
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What was Lipschitz's original motivation for the introduction of Lipschitz continuity?

The concept of Lipschitz continuous mappings is probably at the present time the most important mathematical concept associated with Lipschitz's name. These mappings play an important role in the ...
Christian's user avatar
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2 votes
1 answer
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Who posed the separable quotient problem (and when)?

The (infinte dimensional) separable quotient problem asks whether every infinite dimensional Banach space has a separable infinite dimensional quotient. In the literature I have seen that is problem ...
Christian's user avatar
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6 votes
2 answers
549 views

Are there any records that show how Hilbert came to "invent" or "discover" Hilbert spaces?

I think it's fuzzy as to whether or not this question is appropriate to ask on this site. The reason I ask it that the characteristics of Hilbert spaces are very much used in expressing quantum ...
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