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Register a new userExact flow equation for bound states
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Added by
Stefan Floerchinger
Publication date
2010
fields
Physics
and research's language is
English
Authors
S. Floerchinger
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We develop a formalism to describe the formation of bound states in quantum field theory using an exact renormalization group flow equation. As a concrete example we investigate a nonrelativistic field theory with instantaneous interaction where the flow equations can be solved exactly. However, the formalism is more general and can be applied to relativistic field theories, as well. We also discuss expansion schemes that can be used to find approximate solutions of the flow equations including the essential momentum dependence.
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We propose an exact flow equation for composite operators and their correlation functions. This can be used for a scale-dependent partial bosonization or flowing bosonization of fermionic interactions, or for an effective change of degrees of freedom in dependence on the momentum scale. The flow keeps track of the scale dependent relation between effective composite fields and corresponding composite operators in terms of the fundamental fields.
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