patterns and symmetries Flashcards
it is ideal to stat with the concept of motif
transformation and isometries
a motif is “any non-empty plane set”
according to Grunbaum and Shephard, 1987
a pattern can be described as “____”
repetitions of a motif in the plane
each rotation of a figure is a ____
isometry
“the image of the basic motif under the additional no. of rotation is a pattern”
renee scott 2008
this is not a symmetry as it either shrinks or enlarges a figure
dilation
what is the difference between transformation and isometries
transformation:
changes the size, shape, position of a figure = create a new figure
geometry transoformation. two types are rigid (isometry) and nonrigid
isometry
change the rotation, translation and reflection = does not change the size or shape of figure
what are the types of transformations
translation
rotation
reflection
dilation
initial image =
transformed object =
initial image = pre-image
transformed object = image
briefly explain the different type of transformations
translation: moves object a certain distance (object is not altered)
reflection: mirror image
rotation: turns figure abt a fixed point called the center of rotation (clockwise and counterclockwise)
dilation: changes the SIZE of figure (smaller/ larger) but the SHAPE remains the same
naming of frieze patterns is attributed to ___
john conway, an english mathematician
John Conway is active in ____, ____, ____, ____ and____
finite theory
knot theory
number theory
combinational game theory
coding theory
these are patterns that repeat in a straight vertical or horizontal line
frieze pattern
where can frieze patterns be found
architecture
fabrics
wallpaper boarder
what are the 7 frieze patterns
hop
step
sidle
spinning hop
spinning sidle
jump
spinning jump