Talk:Spiral

message: I'll be translating additional material from the German article :de:Spirale. So as to add some nice illustrations to it, I've asked German Wikipedian :de:Benutzer:Karl Bednarik if he would mind regenerating his contributed images, saved in PNG format (more appropriate for line-art). I'll use the GFDL'd JPGs otherwise. Hooloovoo 13:22, 13 Apr 2005 (UTC)
replies: text: Any progress on that? - RoyBoy 800 02:50, 8 Jun 2005 (UTC)
replies: text: Apparently not. Hooloovoo hasn't been back to Wikipedia since May 1, 2005. Angr/talk 10:11, 2 February 2006 (UTC)
thread_title: Images

message: Perhaps a section dealing with right verus left handed spirals should be considered? --Seans Potato Business 19:39, 28 April 2007 (UTC)
replies: text: Spirals are not symmetric, but I'm not sure what we could say about chirality that would add to the article.  It would be an excellent point in the Art section, at least - and I'm certain there's much more to be said about spiral motifs in art than I'm qualified to say. Wyvern (talk) 06:51, 5 August 2011 (UTC)
thread_title:  Right versus left-handed 

message: Is there a name and equation for a spherical 3d spiral, one that would result if a spiral were drawn on a plane surface that was at the same time rotating? The result would look like a neatly made ball of string of ever increasing diameter.  Just as a spiral as it develops increases the area it "occupies" or "encloses" on a plane surface, so would this spiral/helix "occupy" or "enclose" an ever-increasing volume in space.  I should imagine that if the rate of rotation of the plane surface on which the spiral is drawn was the same as the rate at which the spiral is drawn, then the result would approximate to a sphere, otherwise to a lozenge or 3d eliptical solid (or whatever it may be call
ed).--Philogo 13:00, 23 May 2008 (UTC)
replies: text: Can someone post an mpeg describing the phenomenon above?  If I could see it, that would help me understand it better.  216.99.219.12 (talk) 06:19, 30 May 2009 (UTC)
replies: text: Think of a ball of string, like Ball of string
but much neater. As the spiral is developed it passes though every point in space Philogo (talk) 02:01, 14 December 2010 (UTC)
thread_title: 3d spiral 

message: Is the involute curve considered to be a spiral? If so, it is a noteworthy one with practical applications, and it's inclusion would add a pertinate example to the article. I am not qualified to do this.  —Preceding unsigned comment added by Tonygumbrell (talk • contribs) 17:53, 12 August 2009 (UTC)
thread_title:  The involute 

message: I think the second section adds to the spiral helix confusion. The only senses in which I know where spiral is used to mean helix are a stair case and some authors alternative name  helical computed tomography scanners. The first is more poetic rather than scientific, and the other is by non-native speakers of English (and to some extent is also because it sounds less technical).    Billlion (talk) 11:07, 17 January 2011 (UTC)
replies: text: I agree that there's confusion, but I've always thought of the term "spiral" as being inclusive (a super-set of, if you like) of the term "helix". So a helix is a (particular class of) spiral but a spiral isn't necessarily a helix. Unfortunately I can't find a reference to either confirm or refute this, but I'm pretty sure that a spiral isn't necessarily planar. How, for example, would you describe the conical springs used in electrical devices to make contact with the batteries? They are not helices because I believe a helix has to be cylindrical, so are they spirals? I would say, yes. I think the terms "helix" and "helicoid" are very tightly defined, whereas a "spiral" is a much more general term. Incidentally, the shape in the illustration coloured green is not a helix but a helicoid as it is a surface, not a line. The red object is also a surface, not a line, but it isn't a helicoid. So what is it? A spiral, a "spiroid", or something else? —MegaPedant 06:08, 25 January 2011 (UTC)
replies: text:  Some other examples include Ekman spiral and "spiral binding" (which in some cases can even refer to comb binding).This article goes to substantial length to discuss spirals vs helices, but then also describes in great detail spirals drawn on a sphere. Which begs the question to be asked, what shape is a spiral drawn on a cigar? Is a helix just a spiral drawn on a cylinder? (And for that matter, what shape is a helix viewed projected into 2D?)-- Cesiumfrog (talk) 08:26, 28 December 2012 (UTC)
replies: text:  Sometimes a cigar is just a cigar. Even if a spiral is drawn on it.--Jerzy•t 21:22, 16 July 2013 (UTC)
thread_title: Adds to confusion

message: \begin{cases}
x = (-1)^{^{\left\lceil\frac{t}{2}\right\rceil}} \cdot \left\lceil\frac{t}{4}\right\rceil\\
\\
y = (-1)^{^{\left\lceil\frac{t - 1}{2}\right\rceil}} \cdot \left\lceil\frac{t - 1}{4}\right\rceil\\
\end{cases}
where \left\lceil \bullet \right\rceil is the ceiling function, t \in \mathbb R. The spiral is clockwise if t \leq 0 and anticlockwise if t \geq 0.
--Not A Pipe ¬| 01:40, 2 April 2012 (UTC)
thread_title:  Equations for a square spiral 

message: Theodorus's spiral is described as approx. Archimedean but its radius does not increase constantly. Guess this could be a General Archimedean, or is it more like Logarithmic? Needs clarification, I think. Chiswick Chap (talk) 10:07, 21 May 2012 (UTC)
replies: text: Well let's see:  \theta_n - \theta_{n-1} = \arcsin(\frac{1}{r_n}) \approx r_n^{-1} = n^{-1/2}  ... what does this suggest?  \frac{d\theta}{dn} \approx n^{-1/2} = 1/r \, ; \frac{dr}{dn} = \frac{1}{2} n^{-1/2} \therefore \frac{dr}{d\theta} \approx \frac{1}{2}, so it does approach the Archimedean, if I haven't blundered. —Tamfang (talk) 18:41, 21 May 2012 (UTC)
thread_title: Theodorus

message: At present, this section contains only a diagram of some kind. There ought to be some text also, explaining it. There isn't quite enough information in the diagram to guess what it means so as to produce the missing text. We need a mathematician here, and we need 'em bad! Friendly Person (talk) 15:03, 24 July 2012 (UTC)
replies: text: More than that there is no sourcing as to where this classification came from, it might just be something some has invented. I've now removed the section.--Salix (talk): 15:52, 24 July 2012 (UTC)
thread_title:  Classification of planar spirals 

message: I suggest the article mention the trispiral. Examples are readily found by searching for the term. Thanks!--Lbeaumont (talk) 20:21, 4 April 2013 (UTC)
replies: text: I found a good trispiral image at: http://commons.wikimedia.org/wiki/File:Triple-Spiral-Symbol.svg  — Preceding unsigned comment added by Lbeaumont (talk • contribs) 20:26, 4 April 2013 (UTC)
thread_title:  trispiral 

message: At the risk of putting a band-aid on a severed artery (i.e. focusing too narrowly within an article with much greater problems), an accurately quoted excerpt from the AmHerDict must end with either
:  parallel to the axis....
or
: parallel to the axis; a helix.
instead of the (presumably gradually decaying) travesty that started three and half years ago.
   We're probably talking here about recklessness rather than vandalism, since i suppose we may assume that the distinction between "constant or continuously varying" and "varying" is not discernible to every editor with a passing interest in the subject.--Jerzy•t 05:20, 16 July 2013 (UTC)
replies: text: That's "Am. Her. Dict." --Jerzy•t 08:10, 20 December 2015 (UTC)
thread_title:  Dict quote 

message: I keep looking at the unsourced statement
: While a "spiral" and a "helix" are distinct as technical terms, a helix is sometimes described as a spiral in non-technical usage.
Even if it is true, it is a dismissive and misleading comment that obscures the relationship between spirals and helices, which i am clarifying in place of it.--Jerzy•t 08:06, 16 July 2013 (UTC)
thread_title:  Spirals and helices 

message: Re: "Ouroboros" spiral 
   At  08:19, 28 December 2012,‎ User:Cesiumfrog summarized
: /* Three-dimensional spirals */  tagging dubious synthesis
and placed the  and  tags into the sentence
: This image is reminiscent of an Ouroboros symbol[original research?] and could be mistaken for a torus with a continuously-increasing diameter: [dubious – discuss]
   These prior events provide context:
:# At 14:42, 21 August 2004 de:User:Karl Bednarik made a contrib at de:Spirale#Dreidimensionale Spiralen, adding (without refs)
:## German text and
:## an invocation in the apparently now obsolete image-invocation format :de:Bild:TORUSA-1 Torus mit variablem Ringdurchmesser.jpg, to what is, in the en: article's section in question, aka :File:TORUSA-1 Torus mit variablem Ringdurchmesser.PNG.
:# (Tho i haven't confirmed the timing, i assume the next relevant event was the de: article adding miniatur|Konische Spirale entlang eines Kreises (which is a de: invocation of :File:TORUSA-4 Konische Spirale entlang eines Kreises.PNG.)
:# At 03:29, 20 September 2006 User:Grubber made a contrib at Spiral#Three-dimensional spirals , adding
:## corresponding English text,
:## the invocation of :Image:TORUSA-1 Torus mit variablem Ringdurchmesser.PNG, and
:## the invocation of :File:TORUSA-4 Konische Spirale entlang eines Kreises.PNG (the first image in the subsection)
:#: and summarizing
:#:: Two-dimensional spirals:  add more info and pics from German de:Spirale
:#    (Tho i haven't confirmed the timing, i assume the next relevant event was the de: article replacing that (shared) image invocation (TORUSA-1) with an invocation of .)
   So neither the contributor here nor the contributor at de: whose work they translated has offered a ref, in the going-on 7 years or going-on 9 years since their respective contribs. IMO the Ouroboros connection is of no mathematical value, and just an afterthot to a nice demonstration of that there's an unexpectedly simple mathematical specification (of a conical surface being deformable not just into a valveless sousaphone, but into one that's had its mouthpiece not just stuffed into its bell, but stuffed so deeply in that there's tubing inside tubing inside tubing ... well, to as many levels of self-nesting as you care to ask for). I'm glad to have seen it, and i believe there are people who can write the parametric equations that specify it, and prove theorems about it, but that's less than what WP:V requires, and it's hard to imagine a scenario that would provide us with it.--Jerzy•t 05:25, 17 July 2013 (UTC)
thread_title:  Dubious 

message: I've cleaned up the talk page hiding a lot of images are unrelated to the discussion.--Salix alba (talk): 18:50, 24 October 2015 (UTC)
thread_title: Random Images

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Participate in the deletion discussion at the . —Community Tech bot (talk) 03:04, 9 January 2020 (UTC)
thread_title:  A Commons file used on this page has been nominated for deletion