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On the c-theorem in more than two dimensions

A. Cappelli·G. D'Appollonio·R. Guida·N. Magnoli
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Abstract

Several pieces of evidence have been recently brought up in favour of the c-theorem in four and higher dimensions, but a solid proof is still lacking. We present two basic results which could be useful for this search: i) the values of the putative c-number for free field theories in any even dimension, which illustrate some properties of this number; ii) the general form of three-point function of the stress tensor in four dimensions, which shows some physical consequences of the c-number and of the other trace-anomaly numbers.

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A. Cappelli, G. D'Appollonio, R. Guida, N. Magnoli. 2000-09-15. On the c-theorem in more than two dimensions. https://arxiv.org/abs/hep-th/0009119

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