Talk:Golden spiral

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	This article is related to WikiProject Golden ratio, an attempt to write quality articles about the golden ratio in all of its many forms. If you would like to participate, you can edit the article attached to this page, or visit the project page, where you can join the project and contribute to the discussion.
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Assessment: Hello all, and thank you for contributing to this article. I'm part of the Wikipedia:WikiProject Golden ratio team, and I'm reviewing this page. I'm currently giving it a grade of Start on the Wikipedia 1.0 Assessment Scale and an importance of Top on this importance scale. For information on improving this article, please visit the WikiProject Golden ratio Project Page. My reasoning is as follows: Good start but needs expansion. Adam McCormick (talk) 00:54, 21 March 2008 (UTC)

[edit] Equiangular spiral

There is another name for this spiral (see heading) I think. This is because if you draw 8 lines from the centre of the spiral, the angle at which the spiral intersects them is always the same. Would this be worth mentioning?--CarrotMan 06:07, 19 October 2006 (UTC)

The golden spiral is an equiangular spiral, but not the only one. It's already in the first sentence, if not explicitly. Melchoir 23:13, 23 October 2006 (UTC)

[edit] The formula

Why not use the formula from logarithmic spiral? The current scheme with b raised to a power of angle in degrees is, I bet, not in any verifiable source, as it is abhorrent to a mathematician to do such a thing. It would be nice if this article would say what value of b makes the logarithmic spiral a golden spiral, instead of defining a couple of new idiosyncratic b's. Dicklyon 06:49, 22 November 2006 (UTC)

I don't really understand the last comment. The form r=ab^θ is a simple polar exponential equation. There's nothing wrong or abhorrent about it. The equation used in the logarithmic spiral article, r =ae^θt, is simply the same thing, using the natural base, e. The previous comment also states that the article doesn't give the values for b that make a golden spiral, when in fact those values are calculated for both radians and degrees. So either I'm really missing something, or the previous commenter doesn't understand the math.Goldbren 19:41, 8 June 2007 (UTC)

I think I understand and sympathize with the comment. It's really three parts:

• 1. why use a different formula, and a different definition of b, than what logarithmic spiral uses?
• 2. what formula is used in verifiable sources? probably not this one.
• 3. raising a number to a power that is an angle is "abhorrent" because an angle is not non-dimensional, unless maybe if you want to call radians non-dimensional; b in the exponent is a scale factor with units of inverse angle, but b as the base is weird.

Dicklyon 02:31, 9 June 2007 (UTC)

I can see now why I sympathize with the comment: I wrote it! I hadn't noticed that until now. Dicklyon 05:12, 9 June 2007 (UTC)

OK, I fixed it to use b the way the logarithmic spiral does, and put the other way with c as an alternate. Dicklyon 05:58, 9 June 2007 (UTC)