Borromean Triangles and Prime Knots in an Ancient Temple - Indian ...
Borromean Triangles and Prime Knots in an Ancient Temple - Indian ...
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RESONANCE May 2007<br />
GENERAL ARTICLE<br />
<strong>Borrome<strong>an</strong></strong> <strong>Tri<strong>an</strong>gles</strong> <strong><strong>an</strong>d</strong> <strong>Prime</strong> <strong>Knots</strong> <strong>in</strong> <strong>an</strong><br />
<strong>Ancient</strong> <strong>Temple</strong><br />
The article is about mathematical motifs of modern <strong>in</strong>terest<br />
such as remarkable l<strong>in</strong>ks <strong><strong>an</strong>d</strong> knots that were found at a 6th<br />
century Chennai temple. Introduc<strong>in</strong>g these mathematical<br />
objects we discuss their timeless <strong><strong>an</strong>d</strong> universal appeal as well<br />
as po<strong>in</strong>t to possible reasons for their symbolic use <strong>in</strong> <strong>an</strong>cient<br />
Indi<strong>an</strong> temples.<br />
1. Introduction<br />
Arul Lakshm<strong>in</strong>aray<strong>an</strong><br />
On a recent visit to <strong>an</strong> <strong>an</strong>cient temple <strong>in</strong> Thiruv<strong>an</strong>mayur, South<br />
Chennai, we observed that there are a series of pillars with<br />
beautiful <strong><strong>an</strong>d</strong> remarkable geometric designs that are mathematical<br />
motifs of contemporary scientific <strong>in</strong>terest. The plausible<br />
reasons for their appear<strong>an</strong>ce <strong>in</strong> this temple are not hard to see, but<br />
we use this as <strong>an</strong> opportunity to relate a fasc<strong>in</strong>at<strong>in</strong>g bit of story<br />
<strong>in</strong>volv<strong>in</strong>g recurrent universal symbolism, physics <strong><strong>an</strong>d</strong> mathematics.<br />
The temple is named after the presid<strong>in</strong>g deity ‘Marundheeswarar’,<br />
which tr<strong>an</strong>slates to ‘Lord of Medic<strong>in</strong>e’. The motifs<br />
surround the s<strong>an</strong>ctum of the goddess ‘Tripurasundari’, the “beautiful<br />
lady of the three cities”. The number three is crucial <strong>in</strong> these<br />
motifs <strong><strong>an</strong>d</strong> the irreducible tripartite nature of the div<strong>in</strong>ity is<br />
emphasized through the topology of l<strong>in</strong>ks <strong><strong>an</strong>d</strong> knots.<br />
The first of the patterns is a set of three identical overlapp<strong>in</strong>g<br />
equilateral tri<strong>an</strong>gles at whose center is a four petalled flower<br />
(Figure 1). Unlike the two-dimensional y<strong>an</strong>tras which typically<br />
have several overlapp<strong>in</strong>g tri<strong>an</strong>gles, this one is sculpted with the<br />
third dimension <strong>in</strong> m<strong>in</strong>d; we c<strong>an</strong> make out when one tri<strong>an</strong>gle goes<br />
‘over’ <strong>an</strong>other. The three tri<strong>an</strong>gles overlap <strong>in</strong> a very specific <strong><strong>an</strong>d</strong><br />
remarkable way: no two of the three tri<strong>an</strong>gles are l<strong>in</strong>ked to each<br />
other, but the three are <strong>in</strong>extricably collectively l<strong>in</strong>ked; if <strong>an</strong>y one<br />
Arul Lakshm<strong>in</strong>aray<strong>an</strong> is at<br />
IITM, Chennai. His<br />
research <strong>in</strong>terests lie <strong>in</strong><br />
classical <strong><strong>an</strong>d</strong> qu<strong>an</strong>tum<br />
chaos, qu<strong>an</strong>tum <strong>in</strong>forma-<br />
tion theory <strong><strong>an</strong>d</strong> computa-<br />
tion. Start<strong>in</strong>g out as a<br />
mech<strong>an</strong>ical eng<strong>in</strong>eer, he<br />
moved to more esoteric<br />
forms of mech<strong>an</strong>ics <strong><strong>an</strong>d</strong> is<br />
currently ent<strong>an</strong>gled with<br />
chaos. He is also <strong>in</strong>terested<br />
<strong>in</strong> t<strong>an</strong>tra, without the goat<br />
Keywords<br />
sacrifices, etc.<br />
<strong>Borrome<strong>an</strong></strong> l<strong>in</strong>ks, topology,<br />
knots.<br />
41
Figure 1. The <strong>Borrome<strong>an</strong></strong><br />
tri<strong>an</strong>gles <strong>in</strong> the Marundheeswarar<br />
temple.<br />
From a physicist’s<br />
viewpo<strong>in</strong>t, <strong>in</strong> the<br />
pattern of tri<strong>an</strong>gles<br />
<strong>in</strong> Figure 1, there<br />
are no ‘two-body’<br />
correlations while<br />
there is <strong>an</strong><br />
essential ‘three-<br />
body’ correlation.<br />
GENERAL ARTICLE<br />
of the tri<strong>an</strong>gles is removed the other two fall apart as well. From<br />
a physicist’s viewpo<strong>in</strong>t, there are no ‘two-body’ correlations<br />
while there is <strong>an</strong> essential ‘three-body’ correlation.<br />
2. Brunni<strong>an</strong> L<strong>in</strong>ks, <strong>Borrome<strong>an</strong></strong> Circles <strong><strong>an</strong>d</strong> <strong>Tri<strong>an</strong>gles</strong><br />
Modern mathematics classifies this object as a ‘Brunni<strong>an</strong> l<strong>in</strong>k’.<br />
Formally a l<strong>in</strong>k is a collection of ‘knots’ that do not <strong>in</strong>tersect each<br />
other, but may otherwise be l<strong>in</strong>ked, such as simply two <strong>in</strong>terl<strong>in</strong>ked<br />
r<strong>in</strong>gs. A ‘knot’ conforms to our conventional notion of a str<strong>in</strong>g<br />
loop<strong>in</strong>g around itself, but mathematici<strong>an</strong>s prefer that the ends of<br />
the str<strong>in</strong>g be jo<strong>in</strong>ed together. A s<strong>in</strong>gle str<strong>in</strong>g that is not knotted at<br />
all, <strong><strong>an</strong>d</strong> is therefore called <strong>an</strong> ‘unknot’, is topologically a circle. A<br />
Brunni<strong>an</strong> l<strong>in</strong>k (after H Brunn, Germ<strong>an</strong> mathematici<strong>an</strong> who published<br />
his work on knot theory <strong>in</strong> the late n<strong>in</strong>eteenth century) is a<br />
l<strong>in</strong>k such that if <strong>an</strong>y one of the components is removed, the<br />
rema<strong>in</strong><strong>in</strong>g ones become ‘trivial’ <strong><strong>an</strong>d</strong> fall apart <strong>in</strong>to unl<strong>in</strong>ked<br />
unknots. It is clear that the three tri<strong>an</strong>gles of the Tripurasundari<br />
temple form precisely such a l<strong>in</strong>k.<br />
However the best known <strong><strong>an</strong>d</strong> simplest example of a Brunni<strong>an</strong> l<strong>in</strong>k<br />
is the <strong>Borrome<strong>an</strong></strong> circles, three circles <strong>in</strong>terl<strong>in</strong>ked <strong>in</strong> such a m<strong>an</strong>ner<br />
that no two of them are l<strong>in</strong>ked but all three are simult<strong>an</strong>eously<br />
42 RESONANCE May 2007
RESONANCE May 2007<br />
GENERAL ARTICLE<br />
l<strong>in</strong>ked (Figure 2). The name derives from the medieval aristocratic<br />
Borromeo family from northern Italy who used this symbol<br />
extensively, <strong>in</strong>clud<strong>in</strong>g <strong>in</strong> their coat of arms. It is presumed that it<br />
signified the <strong>in</strong>separable union of three powerful families at that<br />
time. The symbol however has been found <strong>in</strong> several other places<br />
<strong><strong>an</strong>d</strong> predates the medieval Itali<strong>an</strong> family. It appears that a version<br />
of the Brunni<strong>an</strong> l<strong>in</strong>ks with three tri<strong>an</strong>gles appears on 7th century<br />
Sc<strong><strong>an</strong>d</strong><strong>in</strong>avi<strong>an</strong> rune stones where the god Od<strong>in</strong> is shown with these<br />
symbols called ‘valknuts’, me<strong>an</strong><strong>in</strong>g sla<strong>in</strong> warriors’ knots. The<br />
l<strong>in</strong>ks found on the pillars of the Marundheeswarar temple appear<br />
to be a symmetrical version of this symbol. <strong>Borrome<strong>an</strong></strong> motifs<br />
have also been found <strong>in</strong> Jap<strong>an</strong>ese shr<strong>in</strong>es <strong><strong>an</strong>d</strong> family emblems,<br />
<strong><strong>an</strong>d</strong> <strong>in</strong> medieval Christi<strong>an</strong> iconography where it reconciles monotheism<br />
with the potential polytheism implied by the Tr<strong>in</strong>ity of the<br />
Father, the Son <strong><strong>an</strong>d</strong> the Holy Ghost.<br />
While the <strong>Borrome<strong>an</strong></strong> circles <strong><strong>an</strong>d</strong> tri<strong>an</strong>gles are topologically<br />
similar, they are geometrically quite different. It has been established<br />
mathematically, fairly recently, that <strong>Borrome<strong>an</strong></strong> circles of<br />
<strong>an</strong>y relative sizes are impossible. However it is possible to<br />
construct <strong>Borrome<strong>an</strong></strong> configurations with ellipses of arbitrarily<br />
small eccentricities . Thus there c<strong>an</strong>not be <strong>an</strong> actual three-dimensional<br />
realization of the <strong>Borrome<strong>an</strong></strong> circles. This constra<strong>in</strong>t of<br />
geometry does not forbid <strong>Borrome<strong>an</strong></strong> configurations for other<br />
shapes such as ellipses, tri<strong>an</strong>gles or golden rect<strong>an</strong>gles. Golden<br />
rect<strong>an</strong>gles are those whose sides are of the golden ratio; three<br />
such orthogonal rect<strong>an</strong>gles c<strong>an</strong> be <strong>in</strong>scribed <strong>in</strong> a regular icosahedron<br />
(polyhedra with 20 faces, each <strong>an</strong> equilateral tri<strong>an</strong>gle).<br />
There are also Brunni<strong>an</strong> l<strong>in</strong>ks when the number of components n<br />
is larger th<strong>an</strong> 3. In this case there could be situations where no two<br />
components are l<strong>in</strong>ked, but there is a nontrivial subl<strong>in</strong>k. Such<br />
l<strong>in</strong>ks are called ‘<strong>Borrome<strong>an</strong></strong>’, as opposed to Brunni<strong>an</strong> where<br />
every s<strong>in</strong>gle subl<strong>in</strong>k is trivial.<br />
The Institute of Mathematical Sciences at Chennai, <strong>in</strong>cidentally<br />
not far from the Marundheeswarar temple, has recently adopted<br />
this ‘golden’ version of the <strong>Borrome<strong>an</strong></strong> l<strong>in</strong>ks for its logo. The<br />
Figure2. The classic <strong>Borrome<strong>an</strong></strong><br />
r<strong>in</strong>gs.<br />
There c<strong>an</strong>not be<br />
<strong>an</strong> actual three-<br />
dimensional<br />
realization of the<br />
<strong>Borrome<strong>an</strong></strong> circles.<br />
43
The universality of<br />
the <strong>Borrome<strong>an</strong></strong><br />
symbol is very<br />
remarkable as it is<br />
found <strong>in</strong> disparate<br />
cultures <strong><strong>an</strong>d</strong> times.<br />
An example of a<br />
situation where a 2-<br />
body configuration is<br />
not stable, but a 3-<br />
body one is, is<br />
provided by ‘halo<br />
nuclei’ with some<br />
neutrons loosely<br />
bound to a core.<br />
GENERAL ARTICLE<br />
International Mathematical Union adopted a three component<br />
<strong>Borrome<strong>an</strong></strong> l<strong>in</strong>k, which m<strong>in</strong>imized the l<strong>in</strong>k length when tied with<br />
a rope of unit diameter, as their logo <strong>in</strong> August 2006. The<br />
Australi<strong>an</strong> artist John Rob<strong>in</strong>son has made <strong>Borrome<strong>an</strong></strong> sculptures<br />
us<strong>in</strong>g various shapes <strong>in</strong>clud<strong>in</strong>g tri<strong>an</strong>gles. It is <strong>in</strong>deed a lot of fun<br />
<strong><strong>an</strong>d</strong> challenge to take some cardboard <strong><strong>an</strong>d</strong> create ones own threedimensional<br />
version of the <strong>Borrome<strong>an</strong></strong> tri<strong>an</strong>gles whose projection<br />
is found <strong>in</strong> the temple. Once created it is <strong>an</strong> object that is often the<br />
nucleus of conversations on <strong>Borrome<strong>an</strong></strong> matters! The universality<br />
of the <strong>Borrome<strong>an</strong></strong> symbol is very remarkable as it is found <strong>in</strong><br />
disparate cultures <strong><strong>an</strong>d</strong> times. One of my personal favourites is a<br />
<strong>Borrome<strong>an</strong></strong> configuration <strong>in</strong>volv<strong>in</strong>g a doughnut, a coffee mug <strong><strong>an</strong>d</strong><br />
a computer mouse with cable which forms the logo of the Topological<br />
Qu<strong>an</strong>tum Comput<strong>in</strong>g project at Indi<strong>an</strong>a University. This<br />
<strong><strong>an</strong>d</strong> other logos, as well as a considerable wealth of <strong>in</strong>formation<br />
on <strong>Borrome<strong>an</strong></strong> l<strong>in</strong>ks is available <strong>in</strong> the website http://<br />
www.liv.ac.uk/~spmr02/r<strong>in</strong>gs, which is one of several sites that<br />
deal with matters <strong>Borrome<strong>an</strong></strong>. <strong>Ancient</strong> Indi<strong>an</strong> uses of the symbol<br />
which must <strong>in</strong>deed be quite prevalent however do not seem to be<br />
documented.<br />
<strong>Borrome<strong>an</strong></strong> Metaphors <strong>in</strong> Physics<br />
The adjective <strong>Borrome<strong>an</strong></strong> is <strong>in</strong> use <strong>in</strong> few-body qu<strong>an</strong>tum systems<br />
– it describes the situation where a 2-body configuration is not<br />
stable, while a 3-body configuration may be. An example is<br />
provided by ‘halo nuclei’ with some neutrons loosely bound to a<br />
core, such as <strong>in</strong> the case of 6 He, which is stable aga<strong>in</strong>st dissociation<br />
while 5 He is not. Thus while the 3-body configuration<br />
<strong>in</strong>volv<strong>in</strong>g (,n,n) is stable (there exists a bound state), the 2-body<br />
ones (,n) <strong><strong>an</strong>d</strong> (n,n) <strong>in</strong>volv<strong>in</strong>g a Helium nucleus () <strong><strong>an</strong>d</strong> a neutron<br />
(n) or just two bare neutrons are unstable (there are no bound<br />
states).<br />
Another use of the <strong>Borrome<strong>an</strong></strong> l<strong>in</strong>ks as a descriptive metaphor <strong>in</strong><br />
qu<strong>an</strong>tum physics is <strong>in</strong> the study of ent<strong>an</strong>gled states. Ent<strong>an</strong>glement<br />
is a peculiar qu<strong>an</strong>tum correlation that we do not observe <strong>in</strong><br />
our everyday ‘classical’ world, but which could be a crucial<br />
44 RESONANCE May 2007
RESONANCE May 2007<br />
GENERAL ARTICLE<br />
resource for qu<strong>an</strong>tum computers, computers that are presumably<br />
much more powerful th<strong>an</strong> the ones we use today. There are states<br />
of three particles such that <strong>an</strong>y two of them are not ent<strong>an</strong>gled, that<br />
is, if one had access to only a pair of the particles they could be<br />
prepared <strong>in</strong> isolation, but if taken together the three are highly<br />
ent<strong>an</strong>gled <strong><strong>an</strong>d</strong> thus they c<strong>an</strong>not be prepared <strong>in</strong>dividually. Aga<strong>in</strong> as<br />
this is very suggestive of <strong>Borrome<strong>an</strong></strong> r<strong>in</strong>gs, physicist P K Arav<strong>in</strong>d,<br />
of the Worcester Polytechnic Institute, talked of ‘<strong>Borrome<strong>an</strong></strong><br />
ent<strong>an</strong>glement’, although he used a slightly different notion for the<br />
equivalent action of remov<strong>in</strong>g one r<strong>in</strong>g. The Greenberger–Horne–<br />
Zeil<strong>in</strong>ger (GHZ) state<br />
| GHZ <br />
1 <br />
2<br />
is of three sp<strong>in</strong> 1/2 particles (| <strong><strong>an</strong>d</strong> | are states of sp<strong>in</strong>-<strong>an</strong>gular<br />
momentum of <strong>an</strong>y one sp<strong>in</strong> along the z direction be<strong>in</strong>g ±h/2).<br />
Us<strong>in</strong>g the GHZ state, Arav<strong>in</strong>d po<strong>in</strong>ts out that measur<strong>in</strong>g the z<br />
component of <strong>an</strong>y one sp<strong>in</strong> puts the other two <strong>in</strong> either the or<br />
state, <strong>in</strong> either case these are unent<strong>an</strong>gled. The connections<br />
between knot theory <strong><strong>an</strong>d</strong> qu<strong>an</strong>tum ent<strong>an</strong>glement are currently<br />
be<strong>in</strong>g studied.<br />
There are m<strong>an</strong>y other contexts <strong>in</strong> which <strong>Borrome<strong>an</strong></strong> r<strong>in</strong>gs have<br />
appeared, for <strong>in</strong>st<strong>an</strong>ce DNA <strong><strong>an</strong>d</strong> other molecules have been<br />
knotted <strong>in</strong>to <strong>Borrome<strong>an</strong></strong> configurations recently. The French<br />
psycho<strong>an</strong>alyst Jacques Lac<strong>an</strong> used the <strong>Borrome<strong>an</strong></strong> l<strong>in</strong>ks <strong>in</strong> his<br />
lectures, with the elements be<strong>in</strong>g the ‘real’, the ‘symbolic’ <strong><strong>an</strong>d</strong> the<br />
‘imag<strong>in</strong>ary’. Apparently he considered that when <strong>an</strong>y one of these<br />
aspects was absent it resulted <strong>in</strong> psychosis.<br />
Some Speculations <strong><strong>an</strong>d</strong> a <strong>Prime</strong> Knot<br />
Return<strong>in</strong>g to the Thiruv<strong>an</strong>mayur temple, we could ask why such<br />
l<strong>in</strong>ks were carved <strong>in</strong> their pillars. Although this is a forum for<br />
science education, I will venture to elaborate briefly. Indeed a<br />
moderate acqua<strong>in</strong>t<strong>an</strong>ce with the ‘esoteric’ aspects of H<strong>in</strong>duism<br />
gives us several plausible <strong>an</strong>swers.<br />
Another use of the<br />
<strong>Borrome<strong>an</strong></strong> l<strong>in</strong>ks<br />
as a descriptive<br />
metaphor <strong>in</strong><br />
qu<strong>an</strong>tum physics<br />
is <strong>in</strong> the study of<br />
ent<strong>an</strong>gled states.<br />
The connections<br />
between knot theory<br />
<strong><strong>an</strong>d</strong> qu<strong>an</strong>tum<br />
ent<strong>an</strong>glement are<br />
currently be<strong>in</strong>g<br />
studied.<br />
45
Figure 3. A prime knot with<br />
six cross<strong>in</strong>gs, the<br />
Stevedore’s knot, found <strong>in</strong><br />
the Marundheeswarar<br />
temple.<br />
<strong>Knots</strong> have been the<br />
object of mathematical<br />
<strong><strong>an</strong>d</strong> scientific <strong>in</strong>terest<br />
s<strong>in</strong>ce Lord Kelv<strong>in</strong><br />
studied these <strong>in</strong> the<br />
latter half of the<br />
n<strong>in</strong>eteenth century as<br />
a model of atoms.<br />
GENERAL ARTICLE<br />
As mentioned earlier, the pillars of <strong>in</strong>terest are<br />
near the s<strong>an</strong>ctumof the goddess Tri-pura-sundari.<br />
The recurrent theme of the triad is therefore to be<br />
expected. The archetypal m<strong>an</strong>tra AUM conta<strong>in</strong>s<br />
three parts. The yogi’s three pr<strong>in</strong>cipal nadis, the<br />
ida, the p<strong>in</strong>gala <strong><strong>an</strong>d</strong> the central sushumna form<br />
a core t<strong>an</strong>tric triad, which <strong>in</strong>cidentally is also the<br />
symbolism of the staff of Caduceus with two<br />
snakes <strong>in</strong>tertw<strong>in</strong>n<strong>in</strong>g around a staff. There are<br />
three sakthis or powers that derive from the<br />
goddess, the iccha (desire), the gn<strong>an</strong>a (knowledge)<br />
<strong><strong>an</strong>d</strong> the kriya (action), <strong><strong>an</strong>d</strong> the symbol<br />
maybe emphasiz<strong>in</strong>g that without <strong>an</strong>y one of these<br />
the other two are useless. There is of course the<br />
triad of Brahma, Vishnu <strong><strong>an</strong>d</strong> Shiva, or <strong>in</strong> a more<br />
esoteric sense there are three knots (gr<strong>an</strong>this) <strong>in</strong><br />
the hum<strong>an</strong> body, the brahma gr<strong>an</strong>thi <strong>in</strong> the lower<br />
body, the vishnu gr<strong>an</strong>thi <strong>in</strong> the region of the heart<br />
<strong><strong>an</strong>d</strong> the rudra gr<strong>an</strong>thi at the center of the eyebrows. Tripurasundari<br />
is the s<strong>in</strong>gle goddess or power that devolves <strong>in</strong>to these three knots<br />
that essentially creates, susta<strong>in</strong>s <strong><strong>an</strong>d</strong> dissolves.<br />
This theme of a s<strong>in</strong>gle power differentiat<strong>in</strong>g <strong>in</strong>to three while<br />
rema<strong>in</strong><strong>in</strong>g essentially one (the Brahm<strong>an</strong> of the Up<strong>an</strong>ishads) seems<br />
to be brought out <strong>in</strong> <strong>an</strong>other symbol <strong>in</strong> a pillar of the same<br />
s<strong>an</strong>ctum. This represents what looks like a snake knott<strong>in</strong>g itself<br />
up <strong>in</strong>to three parts, thus carry<strong>in</strong>g with<strong>in</strong> it aga<strong>in</strong> the irreducible<br />
triad. If the snake swallows its head or the ends are jo<strong>in</strong>ed, we get<br />
the ‘Stevedore’s’ knot, which is known from the mathematical<br />
theory of knots to be a ‘prime knot’ with six cross<strong>in</strong>gs. A prime<br />
knot c<strong>an</strong>not be composed of smaller simpler knots. Just as there<br />
are prime <strong>in</strong>tegers out of which all the whole numbers c<strong>an</strong> be<br />
constructed, so also there are prime knots. <strong>Knots</strong> have been the<br />
object of mathematical <strong><strong>an</strong>d</strong> scientific <strong>in</strong>terest s<strong>in</strong>ce Lord Kelv<strong>in</strong><br />
studied these <strong>in</strong> the latter half of the n<strong>in</strong>eteenth century as a model<br />
of atoms (vortex atoms). This idea was soon ab<strong><strong>an</strong>d</strong>oned, but the<br />
theory of knots stayed on <strong><strong>an</strong>d</strong> was developed <strong>in</strong>to a beautiful<br />
46 RESONANCE May 2007
RESONANCE May 2007<br />
GENERAL ARTICLE<br />
subject. After a lull, there was a resurgence of <strong>in</strong>terest <strong>in</strong> this<br />
subject from about twenty years ago, when sem<strong>in</strong>al results were<br />
found <strong><strong>an</strong>d</strong> concrete connections to modern physics emerged.<br />
Epilogue<br />
Apart from the motifs noted above, the Tripurasundari s<strong>an</strong>ctum<br />
pillars are decorated with other simpler geometric designs, notably<br />
the well-known Y<strong>in</strong>-Y<strong>an</strong>g symbol, hav<strong>in</strong>g a circle divided <strong>in</strong><br />
two halves by smaller semicircles represent<strong>in</strong>g the Y<strong>in</strong> (female,<br />
sakthi) <strong><strong>an</strong>d</strong> the Y<strong>an</strong>g (male, siva) energies. While the temple has<br />
been <strong>in</strong> existence from about the 6th century AD (it has been sung<br />
by Saivite sa<strong>in</strong>ts of the 8th century) <strong><strong>an</strong>d</strong> it has at least 11th century<br />
<strong>in</strong>scriptions, I c<strong>an</strong>not comment on the era <strong>in</strong> which the pillars with<br />
the motifs discussed here were carved. Such motifs are also<br />
certa<strong>in</strong>ly not unique to this temple <strong><strong>an</strong>d</strong> the use of geometric<br />
patterns (y<strong>an</strong>tras) is prevalent <strong>in</strong> both H<strong>in</strong>dusim <strong><strong>an</strong>d</strong> Buddhism.<br />
Further explorations may throw up more <strong>in</strong>trigu<strong>in</strong>g uses of mathematics<br />
to build bridges with the <strong>in</strong>ner worlds that these temples<br />
seek to connect. The <strong>Borrome<strong>an</strong></strong> tri<strong>an</strong>gles or the Stevedore’s knot<br />
as logos of Tripurasundari may be part of a larger spectrum.<br />
Suggested Read<strong>in</strong>g<br />
[1] P R Cromwell, E Beltrami <strong><strong>an</strong>d</strong> M Rampich<strong>in</strong>i, The <strong>Borrome<strong>an</strong></strong> R<strong>in</strong>gs,<br />
Mathematical Intelligencer, Vol.20, No.1, pp.53–62, 1998. (see also the<br />
comprehensivewebsite on<strong>Borrome<strong>an</strong></strong> r<strong>in</strong>gsma<strong>in</strong>ta<strong>in</strong>ed by PRCromwell:<br />
http://www.liv.ac.uk/~spmr02/r<strong>in</strong>gs)<br />
[2] C C Adams, The Knot Book: An Elementary Introduction to the<br />
Mathematical Theory of <strong>Knots</strong>, New York, W H Freem<strong>an</strong>, 1994.<br />
(There are m<strong>an</strong>y excellent websites for knots, for e.g.:<br />
http://www.ics.uci.edu/~eppste<strong>in</strong>/junkyard/knot.html)<br />
[3] P K Arav<strong>in</strong>d, <strong>Borrome<strong>an</strong></strong> ent<strong>an</strong>glement of the GHZ state, <strong>in</strong> Qu<strong>an</strong>tum<br />
Potentiality, Ent<strong>an</strong>glement <strong><strong>an</strong>d</strong> Passion-at-a-Dist<strong>an</strong>ce: Essays for Abner<br />
Shimony, Ed. by R S Cohen, M Horne <strong><strong>an</strong>d</strong> J Stachel (Kluwer, Dordrecht,<br />
1997) (Available at P K Arav<strong>in</strong>d’s homepage:<br />
http://users.wpi.edu/~parav<strong>in</strong>d/publications.html)<br />
Acknowledgements<br />
It is with pleasure that I record<br />
thecooperation of the Marundhe-<br />
eswarar <strong>Temple</strong> authorities who<br />
allowed me to take photographs<br />
with<strong>in</strong> the temple prec<strong>in</strong>cts. I<br />
th<strong>an</strong>k V Balakrishn<strong>an</strong> for sug-<br />
gest<strong>in</strong>g that I write this up for<br />
Reson<strong>an</strong>ce. I am also th<strong>an</strong>kful<br />
to him <strong><strong>an</strong>d</strong> S Lakshmibala for a<br />
careful read<strong>in</strong>g of this article.<br />
Address for Correspondence<br />
Arul Lakshm<strong>in</strong>aray<strong>an</strong><br />
Department of Physics<br />
Indi<strong>an</strong> Institute of Technology<br />
Madras<br />
Chennai, 600036, India.<br />
Email:arul@physics.iitm.ac.<strong>in</strong><br />
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