Kevin's Watch

MsMary wrote:Clearly.

It doesn't move.

I am curious which way you mean this.

The spiral creates an optical illusion that makes it seem like it's moving, although it's really not.

So are you saying you don't see this illusory movement? If so, it would be very curious that you are somehow immune where others are not.

But if you only mean, I can tell it's not really moving, well ... ok. But I am so curious about whether it's the other case that I have to ask.

wayfriend wrote: So are you saying you don't see this illusory movement? If so, it would be very curious that you are somehow immune where others are not.

But if you only mean, I can tell it's not really moving, well ...

I don't know if it's "curious" our not...meaning I never asked anyone about it, maybe it's common...
But in many of those kinds of things, I can force my brain to stop seeing the motion. Some I can't, and the ones I can if I stop focusing there's a little mental jerk and I blink a lot for a bit and a really uncomfortable sensation.

Wikipedia wrote:Saturn's hexagon, a cloud vortex at the planet Saturn's north pole.

But in a strange way it does [more today than yesterday for some reason]. Perhaps like Hamlets madness it is dependant on the direction of the wind.

Wooaah Sorus!

Vraith wrote:

Le Pétermane wrote:
Are helices and spirals related? Helices are cool too

Yes. A helix has to happen
in 3d [at least].

Indeed. There's actually no such thing as a spiral staircase.

I'm guessing a spiral staircase is actually a helix [the hand-rail] going around a central point [the central pole] and would have a 'wheel' appearence [complete with spokes] if viewed from above.

Le Pétermane wrote:I'm guessing a spiral staircase is actually a helix [the hand-rail] going around a central point [the central pole] and would have a 'wheel' appearence [complete with spokes] if viewed from above.

and you would be exactly right. [depending on treat spacing]

Clearly from Hashi's earlier post, there is a lot of maths involved in this - but do spirals and helices have their own 'branch' of mathematics [as it were], or do their maths slot into [say] that of circles and spheres.

[I can imagine a sphere turning on it's axis, with a marker pen travelling at constant speed down the plane of the axis and tracing out a spiral on the sphere's surface as it goes {but, , it's not a spiral is it, because it's in 3D - there must be a name for that!}.]

Le Pétermane wrote:Clearly from Hashi's earlier post, there is a lot of maths involved in this - but do spirals and helices have their own 'branch' of mathematics [as it were], or do their maths slot into [say] that of circles and spheres.

[I can imagine a sphere turning on it's axis, with a marker pen travelling at constant speed down the plane of the axis and tracing out a spiral on the sphere's surface as it goes {but, , it's not a spiral is it, because it's in 3D - there must be a name for that!}.]

there is a lot of math in order to specifically deal with particular kinds of helix/spiral. [like...starting with your tracing example, there can be egg-shaped ones. And they will be different if the egg is horizontally laid, fat end on top, skinny end on top...chicken eggs or emu eggs or lizard eggs...whichever came first].
even in language/speech it is hard to define/delineate.
but a simple twirl of the finger will cross almost all boundaries in a general sense.

The thing you describe, if you'd read my previous, is a technically a helix. mapped onto 2dimensions, it is a spiral. There may well be an specific name for the specific pattern. [there is certainly a specific formula].
I think you're running into the problem between ordinary language and specific language.
The math is complicated...but the concept is easy. Again, the thing you describe is a spiral in ordinary language. In technical/math it is a helix. But the difference is in an additional spacial term.
A circle traced over and over is just a circle...but it BECOMES a helix by adding height.
the thing you describe is a spiral, with height added..therefore a helix [or a helix that becomes a spiral by subtracting height.] A square becomes a cube by adding height.

Le Pétermane wrote:Clearly from Hashi's earlier post, there is a lot of maths involved in this - but do spirals and helices have their own 'branch' of mathematics [as it were], or do their maths slot into [say] that of circles and spheres.

Right they don't really have their own branch...

It's more like your second idea... math people study spirals and helices with the mathematical tools of some branch (say, differential geometry) ...and also use those same tools on circles, ellipses, or spheres, toruses, and such.

Beautiful Linna. A spiral is one of the points where nature and art merge in together and become almost indistinguishable; this is perhaps the scource of their power to reach into us at a very deep level.

kevinswatch.ihugny.com/phpBB2/album_page.php?pic_id=1475

youtu.be/YuqHlv1YPe0

aliantha wrote:youtu.be/YuqHlv1YPe0

https://www.youtube.com/watch?v=N6IUUWzI7vg

Size of this preview: 800 × 600 pixels. Other resolutions: 320 × 240 pixels | 640 × 480 pixels | 1,024 × 768 pixels | 1,280 × 960 pixels.

This was meant to be a picture of 'spyrogyra' [ie the green algae you find in ponds; guess I ain't got my tecnique down yet!

Reposted from the Illusion thread, because I was really tired when I posted it last night...

Speaking of spiral staircases...I climbed this one yesterday at Montauk Point Lighthouse. Lorin declined.

That's only a portion of the stairway, of course. And once you've made your way up those babies, there's a final treat:

It's essentially a ladder. The docent at the top called the climb "the Montauk Stairmaster." He wasn't far off the mark....

It has that solid look of 'Victorian' [yes - wrong country but how else do I describe it ] engineering about it; that and the brickwork would have to put a date of......1870, 1880 on it?

I had a bout with the Spirals when I was in my 30's. Whew....I was never sicker.