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D0-brane tension in string field theory

Matteo Beccaria
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Abstract

We compute the D0-brane tension in string field theory by representing it as a tachyon lump of the D1-brane compactified on a circle of radius $R$. To this aim, we calculate the lump solution in level truncation up to level L=8. The normalized D0-brane tension is independent on $R$. The compactification radius is therefore chosen in order to cancel the subleading correction $1/L^2$. We show that an optimal radius $R^*$ indeed exists and that at $R^*$ the theoretical prediction for the tension is reproduced at the level of $10^{-5}$. As a byproduct of our calculation we also discuss the determination of the marginal tachyon field at $R\to 1$.

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Matteo Beccaria. 2005-08-12. D0-brane tension in string field theory. https://doi.org/10.1088/1126-6708%2F2005%2F09%2F021

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