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arXiv · hep-th/9211049

Semiclassical Tunneling in 1+1 Dimensional String Theory

Julian Lee·Paul F. Mende
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Abstract

We describe time-dependent tunneling of massless particles in 1+1 dimensional string field theory. Polchinski's description of the classical solutions in terms of the Fermi sea is used to identify the leading instanton contribution connecting the two half-lines. The field theory lagrangian is proportional to $1/g^2$, where $g$ is the string coupling constant, but the $S$-matrix for tunneling from one half-line to the other behaves as $\exp(-C/g)$. We note the constant~$C$ involves curious boundary contributions and observe that a prescription connecting the two half-lines unifies treatments of the Fermi level above and below the barrier. We also note the relation to recent work of Brustein and Ovrut.

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Julian Lee, Paul F. Mende. 1992-11-11. Semiclassical Tunneling in 1+1 Dimensional String Theory. https://doi.org/10.1016/0370-2693(93)90979-r

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