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arXiv · 1203.0188

Properties of c_2 invariants of Feynman graphs

Francis Brown·Oliver Schnetz·Karen Yeats
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Abstract

The c_2 invariant of a Feynman graph is an arithmetic invariant which detects many properties of the corresponding Feynman integral. In this paper, we define the c_2 invariant in momentum space and prove that it equals the c_2 invariant in parametric space for overall log-divergent graphs. Then we show that the c_2 invariant of a graph vanishes whenever it contains subdivergences. Finally, we investigate how the c_2 invariant relates to identities such as the four-term relation in knot theory.

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Francis Brown, Oliver Schnetz, Karen Yeats. 2012-03-01. Properties of c_2 invariants of Feynman graphs. https://arxiv.org/abs/1203.0188

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