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arXiv · 1707.09452

Numerical solution of open string field theory in Schnabl gauge

E. Aldo Arroyo·A. Fernandes-Silva·R. Szitas
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Abstract

Using traditional Virasoro $L_0$ level-truncation computations, we evaluate the open bosonic string field theory action up to level $(10,30)$. Extremizing this level-truncated potential, we construct a numerical solution for tachyon condensation in Schnabl gauge. We find that the energy associated to the numerical solution overshoots the expected value $-1$ at level $L=6$. Extrapolating the level-truncation data for $L\leq 10$ to estimate the vacuum energies for $L > 10$, we predict that the energy reaches a minimum value at $L \sim 12$, and then turns back to approach $-1$ asymptotically as $L \rightarrow \infty$. Furthermore, we analyze the tachyon vacuum expectation value (vev), for which by extrapolating its corresponding level-truncation data, we predict that the tachyon vev reaches a minimum value at $L \sim 26$, and then turns back to approach the expected analytical result as $L \rightarrow \infty$.

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E. Aldo Arroyo, A. Fernandes-Silva, R. Szitas. 2017-07-29. Numerical solution of open string field theory in Schnabl gauge. https://doi.org/10.1007/jhep01(2018)007

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