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Conformal boundary conditions for a 4d scalar field
by Lorenzo Di Pietro, Edoardo Lauria, Pierluigi Niro
Submission summary
| Authors (as registered SciPost users): | Edoardo Lauria |
| Submission information | |
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| Preprint Link: | https://arxiv.org/abs/2312.11633v2 (pdf) |
| Date accepted: | March 12, 2024 |
| Date submitted: | March 6, 2024, 9:49 a.m. |
| Submitted by: | Edoardo Lauria |
| Submitted to: | SciPost Physics |
| Ontological classification | |
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| Academic field: | Physics |
| Specialties: |
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| Approach: | Theoretical |
Abstract
We construct unitary, stable, and interacting conformal boundary conditions for a free massless scalar in four dimensions by coupling it to edge modes living on a boundary. The boundary theories we consider are bosonic and fermionic QED$_3$ with $N_f$ flavors and a Chern-Simons term at level $k$, in the large-$N_f$ limit with fixed $k/N_f$. We find that interacting boundary conditions only exist when $k\neq 0$. To obtain this result we compute the $\beta$ functions of the classically marginal couplings at the first non-vanishing order in the large-$N_f$ expansion, and to all orders in $k/N_f$ and in the couplings. To check vacuum stability we also compute the large-$N_f$ effective potential. We compare our results with the the known conformal bootstrap bounds.
Published as SciPost Phys. 16, 090 (2024)