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arXiv · hep-th/9410164

Field Theory of Open and Closed Strings with Discrete Target Space

Ivan K. Kostov
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Abstract

We study a $U(N)$-invariant vector+matrix chain with the color structure of a lattice gauge theory with quarks and interpret it as a theory of open andclosed strings with target space $\Z$. The string field theory is constructed as a quasiclassical expansion for the Wilson loops and lines in this model. In a particular parametrization this is a theory of two scalar massless fields defined in the half-space $\{x\in \Z , τ>0\} $. The extra dimension $τ$ is related to the longitudinal mode of the strings. The topology-changing string interactions are described by a local potential. The closed string interaction is nonzero only at boundary $τ=0$ while the open string interaction falls exponentially with $τ$.

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Ivan K. Kostov. 1994-11-14. Field Theory of Open and Closed Strings with Discrete Target Space. https://doi.org/10.1016/0370-2693(94)01563-r

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