What does orbifold mean?

Orbifolds are in differential geometry what Deligne-Mumford stacks are in algebraic geometry. See also at geometric invariant theory and GIT-stable point. Orbifolds may be regarded as a kind of stratified spaces.

What is an orbifold in string theory?

In string theory, the word “orbifold” has a slightly different meaning, discussed in detail below. In two-dimensional conformal field theory, it refers to the theory attached to the fixed point subalgebra of a vertex algebra under the action of a finite group of automorphisms .

What are orbifolds in differential geometry?

Orbifolds are in differential geometry what Deligne-Mumford stacks are in algebraic geometry. See also at geometric invariant theory and GIT-stable point. If the finiteness condition is dropped one also speaks of orbispaces and generally of stacks. Orbifolds may be regarded as a kind of stratified spaces.

How do you construct a universal covering orbifold?

A universal covering orbifold can be constructed for an orbifold by direct analogy with the construction of the universal covering space of a topological space, namely as the space of pairs consisting of points of the orbifold and homotopy classes of orbifold paths joining them to the basepoint.

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What coins are sold at stack’s Bowers Galleries?

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