Introduction to Mirror Symmetry in Aspects of Topological String Theory

Under the compactification by the Calabi-Yau threefold, the string theory shows there is duality called mirror symmetry, which implies there is an isomorphism between two string theories under the compactifications of two topologically different internal manifolds. By twisting the topological string theory in two methods, the twisted theories named A-model and B-model have an isomorphism to each other under the mirror symmetry.