Gauge invariance in the operator-product expansion in non-Abelian gauge theory. [Ward-Takahashi identities]
Non-gauge-invariant operators appear in addition to manifestly gauge-invariant operators in the operator-product expansion in non-Abelian gauge theories. However, with the help of various Ward-Takahashi identities, it is shown that these operators which are not gauge invariant do not mix with the gauge-invariant operators to all orders in perturbation theory. These ''null'' operators have vanishing matrix elements in the physical subspace. Accordingly, the null operators may be neglected completely in the operator-product expansion, and the anomalous dimensions of gauge-invariant operators can be found by simply examining the mixing between the gauge-invariant operators if the correct separation between the gauge-invariant operators and the null operators is made. Our discussion is restricted to the light-cone-dominant twist-two operators with arbitrary spin. (AIP)
- Research Organization:
- Department of Physics, University of Washington, Seattle, Washington 98195
- OSTI ID:
- 7344699
- Journal Information:
- Phys. Rev., D; (United States), Vol. 14:4
- Country of Publication:
- United States
- Language:
- English
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