How to divide a plane circle into 360 approximately equal arcs

 I accept that one can divide a circle into 12 approximately equal arcs.

I will use the chord associated with this 1/12th arc to divide the 1/12th arc into 5 approximately equal sub arcs. 

 

Expand the circle into one with 5 times the radius. 

Mark off the 1/12th arc on the larger circle by a radial projection. 

Using the cord in the smaller circle. Mark off 5 arcs on the larger circle and the chord on the larger diameter at the circle. 

 

There will be a shortfall in the arc .

 

Project this back radially onto the smaller circle . This will mark off a 1/5th correction arc and it’s associated chord. 

 

Use this correction chord to extend the initial chord marked on the diameter.

Use this chord in the smaller circle to extend the arc , and thereby form a new chord. 

Mark this new chord on the diameter of the larger circle.

Use this chord on the larger circle to extend the initial arc there, and thereby form a new chord. Mark this off on the diameter.

I now can compare 3 corrective chords on the diameter.

 

Use the largest chord that falls short or the least chord that extends over the 1/12th arc when applied 5 times. 

 

Repeat the correction method until one is satisfied they have the best chord to divide the 1/12th arc into 5 sub arcs.

 

Project this sub arc back onto the smaller circle  to divide it into 60 approximately equal arcs. 

 

Bisect these arcs to divide the circle into 120 arcs. 

 

I will now use the chord associated to the 1/120 th arc to trisecting it. 

 

First expand this circle to one 3 times the radius.

Now use the chord to trisect the arc in the larger circle.

 

Follow the correction process above to  find the chord that trisects the 1/120th arc. 

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Simple Approximate methods for dividing the circle or a circular arc

Simple approximate methods for dividing circles and arcs
 
These methods are based on bisecting an angle, bisecting a line, and equilateral triangles.
 
We can demonstrate how to divide a circle into quarters by bisecting a line. By this method we can find the chord that quarters circular arc
 
We can demonstrate that we can divide the circle into 6 equal parts by using equilateral triangles. By this we can find the chord that divides the circular arc into sixths (1/ 6) 
 
Rotating these two chords onto a diameter, the same diameter, enables us to compare the two chords.
 
The chord that divides the circular arc into five equal arcs lies between these two chords on the diameter. We can now find this by trial and error, and using Euclid’s algorithm or method of division. We will know by this process that dividing the circular arc equally does not divide the diameter into equal parts.
 
To trisect semicircle. If we didn’t know that the radius trisects a semicircle, we can proceed in the following manner.
Construct the semicircle, and then construct a semi circle on the same centre which has three times the diameter. Bisect the largest semicircle. This gives us the cord that divides the semicircle into two. Mark off the diameter of the smaller circle on the damage of the larger circle and also Mark off this chord. We know that the chord which trisects a larger semicircle lies between these two chords. We can find it by trial and error and Euclid’s method .
 
In the first description we have one method of trial and error. The interpolation of the correct chord is done on the diameter.
 
In the second description we have two methods of getting the correct chord : one is by using the Arc and the other is by using the chord. Using both together will give us a faster convergence.
This method is worked in the arc and the diameter of the larger circle using estimates and corrections from the smaller circle. The estimates improve as the curvature difference becomes less noticeable in the arc projections.
 
So in the case of the semicircle being divided into three, we use a diameter of the semicircle as the chord estimate in the larger circle. We Mark this off on the diameter of the large circle and then step it off around the circle. It will be too short ( because the curvatures are different) . We then take the shortfall in the larger circle and project it back down on to tthe small circle to give us a one third estimate of the arc length in the larger circle, And the chord  that marks it off.
 
We can use this chord in two ways; on the diameter to extend the first estimate of the chord or on the circle to mark off an estimated third arc length on the circle, enabling us to then draw a revised chord on the circle. Rotating the chord down onto the diameter we can compare the two new chord estimates. The larger one will be used to mark off the new trisection. first. If it is too long then the shorter one will be used.
 
Again the shortfall will be projected down onto the smaller circle in order to obtain a estimate of the third of the shortfall arc  and the associated chord . We know by this process the bounds between which the desired chord  lies as marked out on the diameter of the larger circle. We quickly obtain an accurate approximation if not an accurate result.
 
In this case we check the method because the result should be the radius of the larger circle.
 
The method is applicable to any number of divisions and any general arc.

Circular Proportions

The trisection of an angle is a famous problem used to encourage innovative thinking. However recently , since the algebraic proof of impossibility, it has been used to brainwash vulnerable mathematicians into a hopeless conformity.

The solution was clearly found by the ancient Sumerian and Akkadian peoples , the Dravidian and Harrapan Indus Valley civilisations and the Mongol chinese steppe and Plain civilisations, all of whom had the wheel and the 60 modulo arithmetics.

The issue is a pragmatic metrical one, and relies on skillful Neusis, as well as expertise with circles

Such an expertise is now called sacred geometry, but it is a science of spherical and circular relations. Of all the forms we have explored it is the circle that encodes proportion in its simplest form: one perimeter to 1 diameter!

We all accept that a circle can be patterned by six petals formed by 6 overlapping circles. We accept the number 6 because we see symmetry. This means we cannot distinguish the 6 forms we see in the pattern by any known or used measurement; accept by calculus! In that branch of ” precision” we find pi to be not 3 but 3.1415… Because our calculation is not based on observation but by a division process!

The difference is profound. Do we trust our eyes or our formal calculation process? Both, because as it turns out our ancestors did not need precision. 6 was good enough for them even though we know that it should be 6.28…

When your compasses do not quite meet the diameter we are taught to do it again until it does, because the radius must step 6 times into the circumference! It does not, but by convention we say it does.

The pattern of 6 is so compelling , we want 6 equilateral triangles as a constructed Constant of space. Construct them in a circle and they fit, construct them in a tessellation and they fit, but they do not precisely fit a circle anymore! The construction in the circle has slightly distorted the plane forms.

Using a constant radius we can construct the sacred geometrical flower pattern. That is when we can start to set out proportions . While we ca crowd 6 around a centre of a circle with 1 radius we can crowd 9×6 around a circle with 3 times the radius! This means we can trisect the diamond made of 2 equilateral triangles . But we have to use the chord length of the 1/3 rd circle to step these off on the larger( 3 x ) circle.

This proportion exists in this set up because circles are proportions. Without a rigid measure it is fiddly to do it is much simpler with a set of measuring tools that can retain and transfer these lengths to the proper positions

There exists a circle for which this length is the precise chord which trisect the arc into 3 similar sectors. Finding it by trial and error can be made easier by using the sacred geometry to narrow the search down. The Neusis becomes simpler and more precise.

Draw an angle and make the limbs or rays long enough to step off 3 radii. The radius is the semi circle drawn at the vertex of the angle, extend your compass to 3 radii and draw the semi circle,

Using a pair of rigid divider measure the chord of the angle in the smaller semi circle.

Step this off on the larger arc until step 3( which is too small ) and step 4 (which is too large).

Leaving the dividers fixed , now use the intersection of the upper ray between steps 3 and 4 with the semi circle as the centre for a circle that has a radius given by the displacement to step 4. Retaining that radios go to step 3 and mark an intersect toward 4 as the centre of a second circle through 3

Now using the point of intersection of these circles with the ray draw a semi circle from the vertex. Using the dividers step off to point 2 along this arc. Setting your compass to the displacement from the point on the ray cut by this arc( the same as that cut by circles at 3 and 4) now draw a circle that intersects circles 3 and 4

The circles are a probability space . Where they intersect is probably the point for the radius of a semi circle which can be trisected by the dividers precisely.
There may be 2 intersections that are clear. Choose the one that fits best.
Where these circles cut the upper ray is a point which was used to draw a semi circle. That semi circle will be unable to contain more than two steps within the arc of the angle.

The demonstration relies on neusis so be as accurate as possible.

The empirical deduction is that the 3 x radius semi circle is going to present an arc( the angle) which being less curved will be too big, by a proportion . Points 3 and 4 are used to narrow the space that the sought for circular arc must pass through. By using the 4th point as a radius displacement and drawing a circle the bounds can be seen to decrease until the circle cuts the upper ray. Thus any circle drawn from the vertex passing through that circle has a high probability of approaching the required radius from above.

The second circle passing through point 3 from a marked centre has the probability of a circle approaching the correct circle from below. Thus both bound a circle which will likely contain 3 to 4 steps

The second circle will bound a circle that is likely to contain 2 to 3 steps

Where they intersect has a high probability of being the correct circle requiring precisely 3 steps to equal the angle.

Clearly the dividers must be kept rigid and the stepping off done as accurately as possible.

Should the result not be “perfect” then the two guiding semi circles, just drawn , can be used to repeat the method.

You will find that if the angle is a 60° or 90° or some multiple of those the circles at 3 and 4 will very nearly coincide. Do not neglect to differentiate the points of intersection.

At first I thought this was a method of approximation relying on proportions un related to sacred geometry, but when I saw that the circle count was 4:3 for the 120° I could see then the sacred geometrical pattern peeking through. The first radius would cut the smaller circle into 6, but the chord was cutting the 3 x circle into approximately 12. The circle I sought would be cut precisely into 9 by that same chord.

These are empirical findings, the sort every geometer should be looking for as a matter of professional expertise!

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We mathematicians have become obsolete.

We were doomed to die out as soon as “we” were born in the medieval period as a class of astrologers whose main task was to calculate the positions of planets and stars and the length breadth weights and measures of the empire.

Prior to that only Astrologers were given that respect and position within society, based on the Sumerian and Egyptian empires and their need for insight from the heavenly gods as to the opportune time for any and every venture. Such shamans using various practices were called sages and seers , whose visions were highly sought after and whose interpretations were regarded with awe.

The quest was to see, to visualise how any event would carry out its due process within the heavenly cycles.

It was the Pythagorean school who developed the ancient arts in Astrology and shamanism into a single or Monas-tic tradition. They collected together the worlds knowledge of Astrology and systematised it gradually into a coherent system based on the Mosaics of their Mousaion or temples to the Musai. 

Such temples collected all the traditions and curated them , bringing together a vast worldly knowledge of Astrology and the Arts. To study at one of these Monasteries was to devote ones life to ceaseless research and curation, finding thought patterns that gave you mastery over the worlds astrological and Artistic knowledge, finding those patterns by a gift of the Muses!

The Aristotelian Lyceum replaced that whimsical tradition by hard logical and taxonomic learnings. For that reason alone the position of Mathematikos was doomed!

Prior to Plato extending the reach of the Pythagorean school and praxis into Athens Greece , Pythagoras was reputed to have established a Mousaion in Sicily under the Patronage of a local chieftain who provided the “Monks” with protection in return for their public services of education. Those that came to listen soon divided into the Akoustia and the devotees. 

The Akoustia came to listen to the public teachings but the devotees came to learn and to be inspired of a Muse so as to teach and express the gift of that Muse.

As such there was no formal curriculum as in the Taxonomically driven Aristotelian Lyceum , instead discourses on topics were given by the Mathematikos, those qualified to teach, and debate and discussion ensued. The Monk or devotee was set Koans, test designed to bring them into close vicinity of the Muses. The Musai would then whimsically impart gifts to the Devotee. What they may be would become apparent as the gift was expressed.

One became a Mathematikos, not by examination and jumping over hurdles, but rather by Merit, that is by the acknowledgement of other Mathematikoi and even non Mathematikoi that one had the gift of a Muse, and particularly the gift of astrology and it’s counterpart geometry.

A Mathematikos was thus a gifted person who could reason by the astrological and geometrical patterns of the heavenly Musai, in particular circular or periodic proportions.

The development of the Arithmoi which was the distinguished Pythagorean name for what we now call mosaics was key to all astrology and geometry, for by these fundamental patterns all proportions were distinguished .

When Aristotle failed to attain the Status of Mathrmatikos, it was not because he was not gifted, but rather because he did not merit it among the Pythagoreans. He openly disputed with them over the logic of their principles and while he remained a firm Platonist he broke away from some key Pythagorean teachings. 

Nevertheless others found him to be remarkably gifted and Learned and Philip of Macedonia employed him to tutor his 2 sons Alexander the great and Phillip. Alexander was very taken by Aristotle, regarding him as his Secret diviner, for him alone. Thus he was annoyed to hear that Aristotle had established an Academy to rival the Athenian Platonic outpost of Pythagoreanism.

The fates of empires lead to the dissolution of his academy while the Platonic academy survived until Roman times and even beyond in some meagre way enamoured by enthusiasts. Aristotles one salvation was the Arabs and Islamist rulers who defeating the Hellenists found Aristotles ideas to have been spread by Alexander everywhere. Thus they adopted them as clearly important to developing a strong Empire. 

Later when Rome sacked Athens and the Platonists fled, Pythagorean literature came into the possession of the Islamic scholars, who mistaking it for a version of Aristotelianism mishandled its provenance and bound together two formerly incompatible traditions!

The Pythagoreans were moved to display their philosophy, the Aristotelians were moved to taxonomise it! What we call geometry was and is a counterpart to Astrology, but the principles of both arose out of the Artisanship of the temple builders and mosaic layers, the Tekne or Mechanics in Greek society .

Because of their low status, but absolutely essential skills they were a distinct slave class or worker class. As such they were employed by the wealthy with reasonable respect to their skills, but no high borne would deign to learn such skills! That is until they became a Pythagorean!

In India the Temple builders were again a distinct group and they handed down trade secrets in Ganitas and Sutras that were the aphoristic stock in trade of the Indian temple Astrologers

The Arab empire firmly combined these 2 streams of similar wisdoms into Geometry and Algebra . Between the 2 the Arithmoi sat as a peculiar  skill which eventually in the Arabic universities became Arithmetic of Numbers, and Number theory. It was also called Kaballah by certain foreigners from mQuaballah to calculate, and even called Gematria( from geometria) or later Numerology.

This is the background to what Medieval scholars of the 14 th century began to call Mathematics. From arithmetical arts to arithmetical arts mainly employing the Algebraic rhetoric to mathematics seems to be the uneven course of the spread of this idea that 2 dysfunctional systems can be combined into one subject area.

Finally in the 1800 the crisis was reached, and geometry and mathematics was about to collapse. Algebra came to the rescue and from it analysis, and the problem limb Geometry was left to wither away!

However Hermann Grassmann thought this was a great injustice. He separated the geometry from Arithmetic and pointed out that that just left Formal expertises which were now inter communicant with a vibrant Geometry, Kinematics and Phorometry and Mechanics.

It is the Mechanics who in Archimedes time displayed the circular proportions on the Antikythera mechanism. It is the mechanics who displayed the polynomial calculations on mechanical computers and it is the mechanics and now Technologists who have refined the mechanisms to display the proportions on these mosaic screens,just as the Pythagoreans did.

The movement of the astrological bodies need only to be proportionately displayed, that was the goal of every Pythagorean. By so doing all wisdoms and knowledge can be organised and cohered or adhered to the great cycle and periods of the heavenly gods, and the opportune time for every venture clearly displayed, where possible.

We have no need of Mathematics so called now, because we can see on a computer monitor all we wish to envision, visualise and more!

What we require are those gifted individuals and mechanics who can build curate and maintain our new temples of the Musai.

The Inertial Reference Frame

There appears to be some confusion about Einsteins use of the Newtonian inertial space concept, denoted by the term inertial reference frame.

Newton based his philosophy of measure on 3 absolutes : space,time and force. This in itself represented his elaboration of the Galilean principle expressed in the Dialogo and elsewhere, that the universe was a fractal based on orbits around centres themselves orbiting a centre and so on. Each centre therefore was locally absolute as far as telescope observation could be adduced.

The system of absolutes were a classical assumption reflecting ideas of a perfect reality untouched by human or corruptible ntities, and therefor suitable for general philosophicl investigation without impugning moral character or religious faith

Thus Newton like Aristole started his Philoophy of quantity from what he felt to be the most unimpeachable principled.
His goal was not to determine the nature of observed powers and their cause, but rather to define reliable measures of these powers as they were identified by philosophers. In this way he hoped to improve the quality of philosophical speculation, founding it on a method of quantitative measurements.

The Mechnics of constructing these measures or Metrons were advancing significantly in regard to precision markings and materials or length nd precision time pieces that kept time to an accuracy of a few seconds in the year! These advances in time were due to the Huygens formula for the period of a pendulum swing which basically made it proportional to thr square root of the length producted by a fudge factor.

These advancements went hand in hand with the commercial and trade expansion in Europe and the expansion of naval supremacy in seamanship of the British naval fleet. By these means Britain acquired an empire leading to conquest and olonization and the spread of British imperial weights measures and time.

Ths a ships clock was synchronised at port , taken on a voyage around the world and then compared with the clock not travelled. Since the clocks barly differed the notion of a constant time was born and personified in accurate timepieces!

By this means an inertial reference frame can be established throughout the empire.

The yardstick and the timepiece were now considered as constants and transportable around th world. Thus a local reference system is extended to cover the whole of space . Time was constant, but the event timing would be different at each position because of the circular nature of the globe. Thus the absolute time is never change, but the time relative to an event could be adjusted to local ..”Tyme” that is time oaf an observed event or a record of a posopition of sun, moon and stars.

Thus sunrise in Thailand will say occur at 9 pm in imperils time, but that would be adjusted 6 am local time!

Newtons method of measuring sound dpeed involves a simplelocal measuring system for distance and time. To extend it to other places required individuals with the same yardstick snd timepieces in all parts of thr world. Thus the speed of Sound locally can be determined as well as extra local measures between such observers. This system of observers is the concept of the inertial reference frame system.

The role of the observe is to adjust the time by setting up a relative time system so locals feel resonsbly in sync with the sun, however the absolute time was that which was measured by the timepiece, which was synced to imperial time standards..

Local speed of sound and inertial reference speed of sound were found to cluster around a figure which supported the sumption that it was a constant.

The tendency to assume it was a constant arose out of the limitations in measuring it accurately by pendulum, and the sense of hearing the echo as a constant time interval. On the basis of this assumption newtons work on the compressive wave nature of sound soon added evidence of the constancy of this speed, especially when resonance and other measurements agreed with this assumption.

However it was known that the speed of sound did vary with experimental conditions, and do theoretical models were devised to account for these variations satisfactorily for perceived parameters. The Doppler effect was therefore a revelation.

The effect of assuming a constant speed for sound led philosophers to test that assumption by making deductive predictions. Doppler, on the other hand observed a variation he could not explain by the known parametric modifiers. It required a deep understanding of the relation between pitch and vibration, and vibration as a frequency of a known wave length or precisely a nodal antipodal compression of the air medium.

By this time philosophers had worked out a strict”proportional ratio between pitch and frequency and using the constancy of the speed an empirically observable wave or deformation length. They also were familiar with wave superposition and wave transparency to each other., but they had not had the chance to observe any source moving at speeds substantially close to the speed of sound. In fact it was commonly believed to be impossible for humans to survive such speeds. So it was a good catch by Doppler which not only further supported the wave nature of sound, but it’s constancy.

Thus time and timepieces were validated as also referencing an absolute constant, and the practices of philosophers went unscrutinized until Lorentz, Poincare and others . It just so happened that Einstein was able to draw on these erudite considerations to frame his ideas in1905. His papers rocked the academic world, which until then had stuffily ignored the works of Einsteins predecessors and fellow questioning philosophers. However it was Einstein who got all the glory, a fact that wrinkles to this day!

The practice of mathematical theoreticians in reducing the theory to very special cases allows for some fundamental errors to creep in as well as common sense errors to be excluded. One of the simplest is in terminology.

An event in special relativity in the reduced case is defined by a spacetime coordinate. However an event in any sense is a behaviour or activity, the space time coordinate does not define that! Thus the practice of assuming an event is a function of space time coordinates ensued. This is a simple reversal. Space time coordinates are functions of the event behaviours!

To illustrate. In the inertial reference frame , if I give the location as Rangoon and the imperial time as 8 am , the question is what are the events happening there at that time!. Suppose the event was midday, that in itself makes a nonsense of an imperial time of 8 am! . We avoid this nonsense by stating the event as a parameter of imperial location and imperial time. This is not the usual way we describe an event , but that usual description. Highlights the activity not the dependency on time and location in a universal or imperial sense.. The event is independent of the reference frame . The reference frame is always dependent on the event. I see a behaviour and I establish a reference frame to describe it. So I and the event, the observer and the event determine the reference frame. An inertial reference frame is such because it’s parameters are the observers and the event. In most simple cases the event that defines a reference frame is a swinging pendulum observed by an observer at some location. As the observer relates to that location it does so by relating to the constancy of the swinging pendulum. The constancy or periodicity of that event and the constancy of a yardstick are used to construct the inertial regpference frame. Thus the frame is dependent on the observer and the event, not the other way round.

By this time philosophers had worked out a strict mathematical”

The Conservation of Circular Disc Sector space.

It is my contention that spheres and circular discs formed a prior philosophy upon which Thales drew and taught many concepts of proportion or Logos Analogos relationships of space. However to demonstrate certain transformations of spatial boundaries as being dual requires the flexibility found in material space as not being created or destroyed. The conservation of matter is a common everyday occurrence that it is taken for granted, but in fact material mediums as all alchemists know do not conserve there shape texture and even volume during and after a chemical reaction.

It was a bold proposal that states that the quantity of matter is conserved in a chemical reaction. While it is not drawn attention to this quantity of matter is an Alchemical concept used and defined by Newton as a measure related to the ratio of motives of material and air, and the measure of the volume of that ratio for the bulk of each object.

Enclosing an object in a sturdy glass container allowed one to assume that all quantity of matter in that volume was isolated. . No matter what was in that volume a relative density was assigned to it via the prescribed calculation. For this reason material was not distinguished and became called Mass.

However careful chemists were able to use the mass as a stepping stone to tabulate pure materials and so characterise them. Then the reacting of several materials together in a sealed container could be shown not to alter this mass characteristic, despite the materials being utterly transformed!

The quantity of matter is part of a chain of concepts Newton established to describe a centripetal/ centrifugal measurement system.. It related every part of an isolated system through these force measures

Conservation of space however has a astrological use, where it is assumed that space is absolute, isolated and still. . With such a conception a boundary change does not affect space. In that regard space passes Tintoretto and out of any dynamic boundary, at least absolute space does. Fractal space behaves differently, and do fractal geometry is different.

Suppose now a circle is squashed, then the space that was inside now stands outside the new topological boundary. However for a ” real” object that space would be deformed within the new boundary , possibly acting to restore the boundary to its initial position.

Using absolute space can I demonstrate that a sector is dual to a half of a rectangle formed by the circle radius and the sector arc length?

It is possible to establish this fairly simply providing absolute space is used, and a specific case involving the arc length equal to the circle diameter is used.

The concept requires also a secure definition of a good or true line sometimes confused with a straight line in other contexts where it is not necessarily the case. This good line must be the line of dual seemeia, or indicators of where arcs cross if drawn from 2 fixed centres , using the dual radii for each centre..

Given this good line a circular sector with arc length equal to I diameter of its circle is placed on the line and rolled so that every point on the arc is brought into contact with only one point on the line.. The centre or vertex of this sector moves one diameter tracing out a rectangle with the radius as the other side.

Conservation of space or absolute space means that the space in this rectangle passes through and or is contained within the arc sector.. Thus the rectangle contains some of all the space swept out by the arc sector. In addition all space has passed symmetrically through this rectangular figure, with space entering and leaving the arc at the same rate.relative to this rectangle.

At the end of this role a symmetrical figure represents the whole process. What we note is this symmetry allows us to half all the spaces in the diagram.the rectangle is created by the sector rolling, thus the whole space in the sector has passed into an through this rectangular space.. We see that there is as much outside this space at the beginning as there is at the end. . This rectangular space therefore has transferred its space into the rectangle . At one stage it was wholly inside the complete rectangle to be. So the space in the rectangle is 2 times the space within the sector. If any space was compressed into it the shape would not be symmetrical . It also took all of its fixed boundary o create this shape and mark out the rectangle..

A legitimate question is how do you know it is transformed into the rectangle? The answer is the arc sector is not transformed into the rectangle . It sweeps through the rectangle, creating the rectangle, thus it’s space places itself everywhere in the rectangle..the rectangle thus must be at least one of the 2 sectors in the symmetric form . If it was just less than 2 the sector would would not extend beyond symmetrically. If more than 2 again it would over extend. Precisely 2 retains symmetry and maintains conservation of space.

It is worth establishing this point with several reasonable or proportional examples, after which we may establish the discovery of Archimedes that an object must displace its own space in order to occupy a different space, or more dynamically an object rolling through space must displace multiples of its own space or multiples of its own space must pass through it.. In the case of a circular disc we may then establish a multiple factor of 1/4 the rectangle it cuts out to quantify its space. In the case of a sphere this reduces to 4/24 of the cuboid it cuts out.

The shapes of space formed when working directly with the circle disc or sphere I call Shunyasutras. The ” rectilineal” shapes are distinct because the good or true line is precisely good or true to itself. This good line is defined however by a property of circles that intersect because they are centred at precisely 2 centres.the point of intersection are called dual points. The dual points that define a good line or a true line are intersections of identical radial displacements from the 2 centres. Shapes of space with a true line fit together along those lines precisely or they don’t.. If they do not the shapes are not dual! It is this powerful notion of duality that is carried through from point to curve to line to shape of space as surface or volume.this notion of duality applies to the Shunyasutras, where a curved arc sector if it is dualed is also a good or true curve!

The straight line however has taken a dominant position in our psyche, despite the fact that it is never found in nature. It is a formal construct that dominates human evaluation schemes. This was not always the case. The circle played a deeper magical role in the past particularly in its rivalry with the spiral.

The absolute empirical dominance of the “spiral” shape and dynamic of space is remarkable when one realises how it is obscured from general metrical perception. In distant times past the circle grew to dominate magical lore and triumphed when it was believed to contain or constrain the spiral. Both these. We’re represented as dragons or serpents

However to measure with the circle always required skill and precise application. The precision of dual points as circle reference points came to dominate the practice of measuring with the circle. The straight lined ruler based on a right angled triangle within a semi circle became an indispensable tool of architecture. The lore of circles that underpins it was soon pushed out of the common thought and left for experts and philosophers to investigate. . Thus I have no intuition of duality of the Shunya ultras, how one shape may be used with a transformed one, and what topological constraints are required to declare duality or fit”.

In the case of arc sectors I can show how the rectangle formed between the arc rolled out ant the diameter contains 2 overlapping arc sectors. The question is does the overlap fit the space mot overlapped?to answer that question I have to employ symmetry observations and exhaustive comparisons, which call upon the notion of ” fit” I have established for the straight line.

The circular gnomon and Lunes play a historical part in the metrication of the Shunyasutras

 

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