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arXiv · hep-th/9307108

Classical and Quantized Tensionless Strings

J. Isberg·U. Lindström·B. Sundborg·G. Theodoridis
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Abstract

{}From the ordinary tensile string we derive a geometric action for the tensionless ($T=0$) string and discuss its symmetries and field equations. The Weyl symmetry of the usual string is shown to be replaced by a global space-time conformal symmetry in the $T\to 0$ limit. We present the explicit expressions for the generators of this group in the light-cone gauge. Using these, we quantize the theory in an operator form and require the conformal symmetry to remain a symmetry of the quantum theory. Modulo details concerning zero-modes that are discussed in the paper, this leads to the stringent restriction that the physical states should be singlets under space-time diffeomorphisms, hinting at a topological theory. We present the details of the calculation that leads to this conclusion.

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J. Isberg, U. Lindström, B. Sundborg, G. Theodoridis. 1993-07-16. Classical and Quantized Tensionless Strings. https://doi.org/10.1016/0550-3213(94)90056-6

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