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arXiv · 0910.2746

The Regge Limit for Green Functions in Conformal Field Theory

Tom Banks·Guido Festuccia
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Abstract

We define a Regge limit for off-shell Green functions in quantum field theory, and study it in the particular case of conformal field theories (CFT). Our limit differs from that defined in arXiv:0801.3002, the latter being only a particular corner of the Regge regime. By studying the limit for free CFTs, we are able to reproduce the Low-Nussinov, BFKL approach to the pomeron at weak coupling. The dominance of Feynman graphs where only two high momentum lines are exchanged in the t-channel, follows simply from the free field analysis. We can then define the BFKL kernel in terms of the two point function of a simple light-like bilocal operator. We also include a brief discussion of the gravity dual predictions for the Regge limit at strong coupling.

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Tom Banks, Guido Festuccia. 2009-10-14. The Regge Limit for Green Functions in Conformal Field Theory. https://doi.org/10.1007/jhep06(2010)105

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