{ "id": "1603.08267", "version": "v1", "published": "2016-03-27T22:51:14.000Z", "updated": "2016-03-27T22:51:14.000Z", "title": "Quantum Revivals in Conformal Field Theories in Higher Dimensions", "authors": [ "John Cardy" ], "comment": "19 pages, 14 figures", "categories": [ "cond-mat.stat-mech", "hep-th" ], "abstract": "We investigate the behavior of the return amplitude ${\\cal F}(t)= |\\langle\\Psi(0)|\\Psi(t)\\rangle|$ following a quantum quench in a conformal field theory (CFT) on a compact spatial manifold of dimension $d-1$ and linear size $O(L)$, from a state $|\\Psi(0)\\rangle$ of extensive energy with short-range correlations. After an initial gaussian decay ${\\cal F}(t)$ reaches a plateau value related to the density of available states at the initial energy. However for $d=3,4$ this value is attained from below after a single oscillation. For a holographic CFT the plateau persists up to times at least $O(\\sigma^{1/(d-1)} L)$, where $\\sigma\\gg1$ is the dimensionless Stefan-Boltzmann constant. On the other hand for a free field theory on manifolds with high symmetry there are typically revivals at times $t\\sim\\mbox{integer}\\times L$. In particular, on a sphere $S_{d-1}$ of circumference $2\\pi L$, there is an action of the modular group on ${\\cal F}(t)$ implying structure near all rational values of $t/L$, similarly to what happens for rational CFTs in $d=2$.", "revisions": [ { "version": "v1", "updated": "2016-03-27T22:51:14.000Z" } ], "analyses": { "keywords": [ "conformal field theory", "quantum revivals", "higher dimensions", "free field theory", "compact spatial manifold" ], "note": { "typesetting": "TeX", "pages": 19, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2016arXiv160308267C", "inspire": 1435081 } } }