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arXiv · hep-th/9702185

String Tension and the Generation of the Conformal Anomaly

A. Nicolaidis·J. E. Paschalis·P. I. Porfyriadis
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Abstract

The origin of the string conformal anomaly is studied in detail. We use a reformulated string Lagrangian which allows to consider the string tension $T_{0}$ as a small perturbation. The expansion parameter is the worldsheet speed of light c, which is proportional to $T_{0}$ . We examine carefully the interplay between a null (tensionless) string and a tensionful string which includes orders $ c^{2} $ and higher. The conformal algebra generated by the constraints is considered. At the quantum level the normal ordering provides a central charge proportional to $ c^{2} $. Thus it is clear that quantum null strings respect conformal invariance and it is the string tension which generates the conformal anomaly.

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A. Nicolaidis, J. E. Paschalis, P. I. Porfyriadis. 1998-05-26. String Tension and the Generation of the Conformal Anomaly. https://doi.org/10.1103/physrevd.58.047901

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