cassette

THE BRIDGES THAT LED TO A
NEW BRANCH IN MATHEMATICS
AND GEOMETRY
BY MELIH KANATLAR
Graph Theory is a branch of mathematics that uses
vertices and edges to represent objects and the
relationships between them. In the modern world,
it is mostly used in the creation and maintenance
of computer networks. Other uses include subway
networks, models of social relationships, maps, and
map coloring, and many more. It can even be used to
model something as simple as people in a room and
their handshakes. Graph Theory is easy to
understand, visually representable, and versatile
but its origins come from an old city entertainment
called the “7 Bridge Problem”.
Königsberg was a city in Prussia that birthed a lot of talented mathematicians (Fig1.1). It later
became Kaliningrad as a part of the Soviet Union. Nonetheless, we are interested in a particular
part of the city. A part that includes 4 pieces of land and 7 bridges to be precise (Fig1.2). We have a
hero in our story as well: Leonhard Euler. The story goes like this:
As stated above, there were 4 pieces
of land and 7 bridges connecting
these lands (Fig1.3). The people of
königsberg had a game with the
bridges. They wondered whether
was there any way to walk over all
the bridges once and only once and
return to the same piece of land
where they started the walk. It was
common for people to traverse these
bridges to try and complete the
challenge.
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