• ## Discussion Feed

Vanilla 1.1.9 is a product of Lussumo. More Information: Documentation, Community Support.

1.

In reference to Historical basis and mathematical significance of Riemann surfaces [closed] and the associated meta: http://meta.mathoverflow.net/discussion/1137/historical-basis-rieman-surfaces, I'd like to request assistance from the community to reformulate and repost my question:

"If you consider traditional calculus to mean calculus in one variable, then that leads to complex analysis in one variable. At first it was done on C, but for more flexibility (particularly in relation to speaking about analytic continuation without awkward branch cuts) Riemann introduced the idea of doing complex analysis on a one-dimensional complex manifold, and those are essentially the same thing as Riemann surfaces"

and my subsequent response:

"[following up from you (sic) response-] Was that the primary motivation for Riemann surfaces? ... I'm trying to understand if - (and in what way if applicable) - the Riemann surface concept brought coherence to the ideas in analysis{star}, geometry, and algebra (specifically, the Fundamental Theorem of Algebra (as this theorem, as far I'm aware, required introduction of complex analysis / complex analytic ideas to prove [at least as one of its earlier / earliest proofs])). [{star} to refer to the above statement here: "[theory of Riemann surfaces] is [the] culmination of much of traditional calculus"]".

I'm not searching for textbooks or technical material [except books on the historical genesis and motivating reason(s) for Riemann surfaces]. ... More specifically, [as above], the relation between the birth of Riemann surface theory in light of developments within the three primary branches: geometry, analysis, and algebra.

(Within geometry: the emergence of non-Euclidean geometries: (especially as most of non-Euclidean geometries use the notion of 'manifold' - which, if I'm not mistaken - came from the context of studying Riemann surfaces);

Within analysis: -- KConrad's statement above -- ;

and

Within algebra: the fact that a good number of proofs of the Fundamental Theorem of Algebra require the use of ideas from complex analysis (and, indirectly, relate to Riemann surfaces).)

I want to get an expert's take on the thread's outlined above, and the relation between each other and the concept of Riemann surfaces.

So, basically, that is my question.

Any feedback would be greatly appreciated.

2.

Sadiq, I still don't understand why you are, or seem to be, ignoring the responses you got at SE. KConrad's comment was just that: a brief comment. The responses you got at SE were much more detailed and to my eyes reflect sound understanding of the matter. Really, if I were you, I would take them seriously and seek to understand what is behind them.

I don't know what possible connections you have in mind between the fundamental theorem of algebra and Riemann surfaces or between non-Euclidean geometries and Riemann surfaces, and I don't know why you would be particularly advocating either of those as a major impetus in the historical development. (I'm not denying the existence of connections -- all math is one, you know -- but I'm not at all seeing why those would be major actors in the story.)

If I were you, I would definitely get hold of Weyl's book. My own understanding -- not based on a study of the primary 19th century sources, but on my general experience as a mathematician -- is that Riemann was developing clear geometric intuitions for the study of algebraic curves \$f(z, w) = 0\$ where \$f\$ is a polynomial in two variables with complex coefficients. This is a huge story, related to things like elliptic functions which were much investigated during that time, and had a lot to do with the rise of modern algebraic geometry (cf. Riemann-Roch theorem, for instance, and consideration of the intrinsic geometry of curves).

3.
Sadiq, I don't usually like to jump into the middle of these meta discussions. I haven't followed the fate your question from the beginning, but I suppose that double posting it contributed to its demise. That said, I suspect that there is a reasonable underlying question involving history of mathematics. But I second Todd's suggestion of doing some research before asking again. In addition to Weyl (which is a classic), you might find it worthwhile to get a biography of Riemann. There is one by Laugwitz that I know of. My impression (and it just an impression) is that Riemann's ideas of geometrizing function theory were quite radical at the time. So in way, it was both a continuation of, and a break from, the past.
• CommentAuthorquid
• CommentTimeSep 17th 2011 edited

Donu Arapura, speaking for me only: yes, the general conduct of the OP caused some irritation. However, I also checked quite precisley the contributions here and on math.SE and the main problem I see is the complete absence of even a vague idea of what I consider necessary prerequisites. Moreoever, I do not understand why the two fine answers OP got on MO [important correction, I meant math.SE, not MO, where there are two answers by in some sense anonymous users] are not sufficient. (Actually, for some meaning of understand I think I do understand it, but this is pure snobbery on the OPs side; who most of all seems to want an "expert's take", and the answerers there do not 'advertise' their expert-status enough.)

4.
OK, I plead ignorance. I wasn't aware of the whole convoluted story. I was trying to suggest that a well formulated historical question on some of this stuff would be welcome here (at least by me), but perhaps the OP was after something else. I'll stay out of it from now on.

Best,
Donu Arapura
• CommentAuthorquid
• CommentTimeSep 17th 2011

Dono Arapura: Yes I agree; and personally I found in particular PseudoNeo's answer on math.SE interesting. Sorry, for a typo I made in my original comment (now corrected); I hope it caused no confusion.