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Classical Gravity in 2+1 Dimensions
The first step towards quantizing (2+1)-dimensional general
relativity is to understand the space of classical solutions. One
of the principal advantages of working in 2+1 dimensions is that
for simple enough topologies, this space can be characterized
completely and explicitly. Indeed, there are several such
characterizations, each leading naturally to a different approach
to the quantum theory; by understanding the relationships among
these approaches, one can gain important insights into the
structure of quantum gravity.