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arXiv · 1309.2921

On Scale and Conformal Invariance in Four Dimensions

Anatoly Dymarsky·Zohar Komargodski·Adam Schwimmer·Stefan Theisen
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Abstract

We study the implications of scale invariance in four-dimensional quantum field theories. Imposing unitarity, we find that infinitely many matrix elements vanish in a suitable kinematical configuration. This vanishing is a nontrivial necessary condition for conformality. We provide an argument why this is expected to be a sufficient condition as well, thereby linking scale and conformal invariance in unitary theories. We also discuss possible exceptions to our argument.

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Anatoly Dymarsky, Zohar Komargodski, Adam Schwimmer, Stefan Theisen. 2013-09-11. On Scale and Conformal Invariance in Four Dimensions. https://doi.org/10.1007/jhep10(2015)171

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