Advertisement
I'm exploring a relationship between these two Platonic solids,as I did with the sphere and cube,to see if there is a perceptible dynamic energy between them (as there was with sphere and cube).As usual I am following my curiosity and intuition.My researches on the net uncovered only ONE image of these two shapes intersected with congruent volumes. The author said the sphere symbolized the feminine principle and the tetrahedron the male principle. When these figures are superimposed with congruent volumes it symbolizes BALANCE.
This seems to fit somewhat my own feelings. I am proceeding somewhat blind in this area. I mean,as with the cube and sphere,I trust my own perceptions,i.e. the energy potential and dynamic relationship,but I have no INTELLECTUAL understanding of WHY this dynamic exists.
Can anyone shed light on this phenomena or have any info on any known relationship between the regular tetrahedron and the sphere?
This seems to fit somewhat my own feelings. I am proceeding somewhat blind in this area. I mean,as with the cube and sphere,I trust my own perceptions,i.e. the energy potential and dynamic relationship,but I have no INTELLECTUAL understanding of WHY this dynamic exists.
Can anyone shed light on this phenomena or have any info on any known relationship between the regular tetrahedron and the sphere?
Advertisement
Advertisement
-
Re: Tetrahedron and sphere of congruent volumes superimposed...
Tue, June 16, 2009 - 5:34 PMNew image in this tribes gallery... -
-
Re: Tetrahedron and sphere of congruent volumes superimposed...
Wed, June 17, 2009 - 4:24 AMRelated to the tetrahedron are two spheres which have received much attention. The "twelve-point sphere," discovered by P. M. E. Prouhet (1817-1867) in 1863, is somewhat analogous to the nine-point circle of a triangle. If the perpendiculars from the vertices to the opposite faces of a tetrahedron be concurrent, then a sphere passes through the four feet of the perpendiculars, and consequently through the centre of gravity of each of the four faces, and through the mid-points of the segments of the perpendiculars between the vertices and their common point of intersection. This theorem has been generalized for any tetrahedron; a sphere can be drawn through the four feet of the perpendiculars, and consequently through the mid-points of the lines from the vertices to the centre of the hyperboloid having these perpendiculars as generators, and through the orthogonal projections of these points on the opposite faces.
I would imagine the form you are looking for is the second of these three . . . the surface of the sphere should pass precisely through the midpoint of the tetrahedral vertices. If the tetrahedron vertex length was 1. . . it appears that the radius of the sphere would be approaching 0.61 (PHI) of the tetrahedron vertex length. . . . which would provide the energetic exuberance you have noted . . .
(see equation (15) at mathworld.wolfram.com/Tetrahedron.html) -
-
Re: Tetrahedron and sphere of congruent volumes superimposed...
Wed, June 17, 2009 - 4:25 AMNice piece of work btw :-)
-
Re: Tetrahedron and sphere of congruent volumes superimposed...
Wed, June 17, 2009 - 5:04 AMI decided to test this out in 3d, and found that the 'midsphere' appears slightly larger than the tetra based on this calculation.
The midsphere touches all polyhedron edges of a semiregular or regular polyhedron, as well as the edges of the dual of that solid (Cundy and Rollett 1989, p. 117). Note that the midsphere does not necessarily pass through the midpoints of the edges a polyhedron dual, but is rather only tangent to the edges at some point along their lengths.
Who knows . . .
-
-
-
Re: Tetrahedron and sphere of congruent volumes superimposed...
Wed, June 17, 2009 - 1:40 PMAs i read your post i remembered this post by Sunnely,there are some notes here
regarding form and values,...hope this is helpfull. -
-
Re: Tetrahedron and sphere of congruent volumes superimposed...
Wed, June 17, 2009 - 1:42 PMO'ya the link! www.feandft.com/index2.htm -
-
Re: Tetrahedron and sphere of congruent volumes superimposed...
Wed, June 17, 2009 - 8:45 PMThank you Rik and White Wizard,
for your input.
I have cruised those sites before but not found the exact figure I'm interested in.
Unlike the 12 pointed sphere that is CONTAINED WITHIN THE TETRAHEDRON. this figure has a sphere OF EQUAL VOLUME AS THE TETRAHEDRON...
My model in this tribes gallery is inaccurate in that the stainless sphere needs to be slightly larger ,but a good first attempt ...
I'm content at this point to muddle through on pure intuition. I'm confident I'll eventually learn that which I am to know... -
-
Re: Tetrahedron and sphere of congruent volumes superimposed...
Wed, June 17, 2009 - 9:29 PMi saw that your sphere was relative... glad you admitted it..
you have to simply test the acoustics... as, that is the center of the argument? no? -
-
Re: Tetrahedron and sphere of congruent volumes superimposed...
Wed, June 17, 2009 - 9:43 PMOh yes I admit it...LOL
As I say I'm stumbling blind.Like moving down a long hallway in utter darkness,the only way I know when I'm off course is when I hit the wall...
If I shut up(still the inner voice)and try to SEE instead of merely looking,(relinquish dependency on eyes),I find the direct path.
I stumbled on the relationship between sphere and cube,(of equal volumes)quite by "accident",but seen from another vantage point ,I was SUPPOSED to find that relationship.And the supposition here,sparked by my intuition,is that there is another dynamic relationship between sphere and Tetrahedron(also of equal volumes). This is the way of DISCOVERY for me in this life. I always follow a course of intuition,but it is not until much later that the RELEVANCE of the discovery and or observable phenomena gains pertinence or context.
Is that what you meant by acoustics? -
-
Re: Tetrahedron and sphere of congruent volumes superimposed...
Thu, June 18, 2009 - 8:06 PMthe sphere must be very hard to make... maybe you could cast it, and then polish it...
or you could lathe it, and then polish it...
but being a perfect sphere would only make you notice its imperfections...
acoustically, i wonder: if the sphere contained exactly 2 liters, and the tetrahedron contained also this same volume, would the acoustics resonate the same note? -
-
Re: Tetrahedron and sphere of congruent volumes superimposed...
Fri, June 19, 2009 - 1:31 AMEmphatically no,
Shape has a great deal to do with acoustic resonance.
And the fact of their differing metals would also be a factor affecting acoustics.
I think you realize I'm shaping these 4 round discs on a press with dies to make them convex.
But I'm already planning the next one,and as usual the second iteration will be more refined.(and bigger).
I'll concentrate more on making the two volumes(more) congruent...
Energetically the two shapes have a different signature.
I'm hoping it will be more pronounced in the second iteration.
I am enjoying the LOOK of this piece though,beyond any metaphysical side effects ,so at least it has that going for it even if I don't "discover" any new properties. To me they are pleasing geometric volumes,like the blocks I had as an infant but more high tech somehow.
As always I appreciate everyone's tolerance of my vague wanderings and the stimulation that comments add...
-
-
-
-
-
-