Dilatons Improve (Non)-Goldstones
Fuente:
arXiv
Salvato in:
| Autore principale: | |
|---|---|
| Natura: | Preprint |
| Pubblicazione: |
2023
|
| Soggetti: | |
| Accesso online: | |
| Tags: |
Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
|
| _version_ | 1866912812567101440 |
|---|---|
| author | Zwicky, Roman |
| author_facet | Zwicky, Roman |
| contents | Shift symmetry forbids conformal coupling of Goldstone bosons from internal symmetries, but not for spontaneously broken conformal symmetry. Its Goldstone boson, the dilaton $D$, admits and indeed requires, an improvement term $ {\cal L}_R \propto R e^{-2D/F_D}$ as it realises the Goldstone matrix element in the effective theory. The improvement, combined with Weyl-gauging, enables conformal coupling to Goldstone bosons and other particles of arbitrary Weyl-weight. While improvement does not affect scattering amplitudes in flat space, it impacts gravitational form factors decisively, giving rise to the dilaton pole in the spin-zero channel. We compute leading-order scalar, fermion, pion, and dilaton form factors, confirming low-energy constraints. The dilaton decoupling limit further implies that the operator driving spontaneous chiral symmetry breaking has scaling dimension $Δ= d-2$. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2306_12914 |
| institution | arXiv |
| publishDate | 2023 |
| record_format | arxiv |
| spellingShingle | Dilatons Improve (Non)-Goldstones Zwicky, Roman High Energy Physics - Theory General Relativity and Quantum Cosmology High Energy Physics - Lattice High Energy Physics - Phenomenology Shift symmetry forbids conformal coupling of Goldstone bosons from internal symmetries, but not for spontaneously broken conformal symmetry. Its Goldstone boson, the dilaton $D$, admits and indeed requires, an improvement term $ {\cal L}_R \propto R e^{-2D/F_D}$ as it realises the Goldstone matrix element in the effective theory. The improvement, combined with Weyl-gauging, enables conformal coupling to Goldstone bosons and other particles of arbitrary Weyl-weight. While improvement does not affect scattering amplitudes in flat space, it impacts gravitational form factors decisively, giving rise to the dilaton pole in the spin-zero channel. We compute leading-order scalar, fermion, pion, and dilaton form factors, confirming low-energy constraints. The dilaton decoupling limit further implies that the operator driving spontaneous chiral symmetry breaking has scaling dimension $Δ= d-2$. |
| title | Dilatons Improve (Non)-Goldstones |
| topic | High Energy Physics - Theory General Relativity and Quantum Cosmology High Energy Physics - Lattice High Energy Physics - Phenomenology |
| url | https://arxiv.org/abs/2306.12914 |