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Symmetry in the Arts
In a painting or a sculpture, a
high degree of symmetry suggests formality and is difficult to
combine with the suggestion of movement. While it was typical
of, for example, statuary in ancient
Egyptian art
or medieval European religious painting, it is rarely found in
Western art after the Renaissance. Symmetry, however, features
largely in
crafts.
The forms and decorations of vases, utensils, and other useful
objects, frequently exploit symmetric patterns. Symmetry is
central to much
architecture
as well. Royal palaces, Gothic cathedrals, country houses, and
large civic buildings were normally designed symmetrically,
though since the 20th century asymmetry has been widely used in
both large and small buildings.
There are countless areas in
which the principles of symmetry play an important role. The
different
rhyme
schemes in
poetry
represent different types of symmetry. For example, the rhyme
scheme a b b a shows a kind of reflective symmetry in
time, the rhymes of the last two lines being a mirror image of
those of the first two. There are many types of rhyme scheme
more complex than this, but symmetrical patterns can often be
discovered in them.
Musical forms
reveal similar types of symmetry, too. On the shortest
timescale, musical phrases in most
Western music
usually come in symmetrical pairs, usually two or four bars
long, in which the second phrase seems to answer or complete the
first. On a larger scale, one type of
rondo
has the form ABACABA, which again shows a time symmetry. Such
musical palindromes are employed by composers ranging from
Guillaume de Machaut,
in his
rondeau
Ma Fin est Mon Commencement
(My End is My Beginning), to
Johann Sebastian Bach
(for instance, in the mirror fugue of the gigue from the English
Suite in D minor).
One can also
look at the symmetry of a single motif or ornament. Examples of
such motifs (illustrated from patterns used in batiks) are shown
below. Such ornaments typically have rotational symmetry and/or
reflection symmetry.


A more complex pattern such as the one below can be built up
from simple motifs. Such patterns have translational symmetry in
one direction. Designs or patterns of this kind are known as
strip,
band,
or
frieze patterns.

The motifs used to make such
frieze patterns may be isolated from one another or coalesce
into a "continuous" geometric design along the strip. If a
pattern has translations in two directions, then the pattern is
often referred to as a wallpaper pattern.
Whereas an artist may choose to create a pattern with absolute
and strict adherence in all details to have symmetry in the
pattern, this is not all that common for "tribal" artists or
artisans. Thus, if one looks carefully at a rug which at first
view looks very symmetrical, it is common to see that at a more
detailed level it is not quite totally symmetric either in the
use of the design or of the colors used in different parts of
the design. One can see the small liberties that are taken
either because of the difficulty of making patterns exact by
hand or because the artist wants consciously to make such small
variations. In analyzing the symmetry of such a pattern it
probably makes sense to idealize what the artist has done before
applying some mathematical classification of the symmetry
involved.
In the patterns shown above no color appears. We have a black
design on a white background. However, in discussing the
symmetry of a pattern one can study the symmetry involved if
color is disregarded or by taking color into account. If you
look at the batik below from a symmetry point of view you must
idealize (model) what is going on to use mathematics. This batik
is not infinite in either one or two directions. You must decide
what colors have been used and what is the background color.

Many find it interesting to use
mathematics to decide what symmetry pattern is involved for
various interpretations of the whole or parts of a design.
E. Fedorov
(1859-1919) enumerated the seventeen 2-dimensional patterns in
1891 in a paper which did not receive wide attention because it
was in Russian.
P. Niggli
(1888-1953) and G. Polya (1887-1985) developed the seven
1-dimensional and the seventeen
2-dimensional patterns
in the 1920's; it was through this work that a mathematical
approach to the analysis of symmetry patterns became more widely
known. One extension of this work to color symmetry was
accomplished by H. Woods in the 1930's. It turns out that there
are 46 two-color types of patterns. Subsequently much work has
been done with regard to
studying symmetry
in higher-dimensional spaces and using many colors. Recently
Branko Grünbaum and Geoffrey Shephard, in a long series of joint
papers and in their seminal book Tilings and Patterns,
explored many extensions and facets of pattern, tilings, and
their symmetries. In particular, Grünbaum and Shephard explored
the interaction between symmetry and the use of a motif. This
enabled them, for example, to develop a "finer" classification
of the seven frieze patterns and seventeen wallpaper patterns.
Unfortunately, this work is not as widely known as it should be.
Many people have been
instrumental in disseminating mathematical knowledge of symmetry
and pattern to scholars outside of mathematics as well as to the
general public. One of the most influential and early books of
this kind was Hermann Weyl (1885-1955)'s book Symmetry.
Also noteworthy among these popularizers are Doris
Schattschneider, Branko Grünbaum, Geoffrey Shephard, Marjorie
Senechal, Michele Emmer, H. S. M. Coxeter, Dorothy Washburn (an
anthropologist), Donald Crowe and Kim Williams. These
individuals called attention to the
use of symmetry
as a tool for insight into various aspects of fabrics, ethnic
designs and culture, architecture, and art, as well as to
artists such as Escher whose work tantalizes people with a
mathematical bent.

Symmetry exists in architecture
all around the world. The best known example of this is
the Taj Mahal.
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Exeter Cathedral is built to a highly
symmetrical plan. The west front has obvious
left-right reflection symmetry, and so, less
obviously, does the ground plan. The tower seen
here, for example, is balanced by another that is
not visible in this view. |
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There is an unusually high degree of
symmetry in this 15th-century fresco by Perugino,
Christ Giving the Keys to St Peter. The
positions of the figures closely follow an imaginary
grid with reflection symmetry, the left-hand and
right-hand halves of the grid being mirror-images of
each other. |
SYMMETY IN UKRANIAN EGGS
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