Non-perturbative quantum Galileon in the exact renormalization group. (English) Zbl 1485.83183
Summary: We investigate the non-perturbative renormalization group flow of the scalar Galileon model in flat space. We discuss different expansion schemes of the Galileon truncation, including a heat-kernel based derivative expansion, a vertex expansion in momentum space and a curvature expansion in terms of a covariant geometric formulation. We find that the Galileon symmetry prevents a quantum induced renormalization group running of the Galileon couplings. Consequently, the Galileon truncation only features a trivial Gaussian fixed point.
MSC:
| 83F05 | Relativistic cosmology |
| 83D05 | Relativistic gravitational theories other than Einstein’s, including asymmetric field theories |
| 81T20 | Quantum field theory on curved space or space-time backgrounds |
| 81T17 | Renormalization group methods applied to problems in quantum field theory |
| 35K08 | Heat kernel |
| 17B69 | Vertex operators; vertex operator algebras and related structures |
| 53E10 | Flows related to mean curvature |
| 41A58 | Series expansions (e.g., Taylor, Lidstone series, but not Fourier series) |
| 81R20 | Covariant wave equations in quantum theory, relativistic quantum mechanics |
| 53Z05 | Applications of differential geometry to physics |
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