{ "id": "1811.02387", "version": "v1", "published": "2018-11-06T14:57:56.000Z", "updated": "2018-11-06T14:57:56.000Z", "title": "$L^2$-critical NLS on noncompact metric graphs with localized nonlinearity: topological and metric features", "authors": [ "Simone Dovetta", "Lorenzo Tentarelli" ], "comment": "22 pages, 7 figures. Keywords: metric graphs, NLS, ground states, localized nonlinearity, $L^2$-critical case", "categories": [ "math.AP", "math-ph", "math.FA", "math.MP" ], "abstract": "Carrying on the discussion initiated in (Dovetta-Tentarelli'18), we investigate the existence of ground states of prescribed mass for the $L^2$-critical NonLinear Schr\\\"odinger Equation (NLSE) on noncompact metric graphs with localized nonlinearity. Precisely, we show that the existence (or nonexistence) of ground states mainly depends on a parameter called reduced critical mass, and then we discuss how the topological and metric features of the graphs affect such a parameter, establishing some relevant differences with respect to the case of the extended nonlinearity studied by (Adami-Serra-Tilli'17). Our results rely on a thorough analysis of the optimal constant of a suitable variant of the $L^2$-critical Gagliardo-Nirenberg inequality.", "revisions": [ { "version": "v1", "updated": "2018-11-06T14:57:56.000Z" } ], "analyses": { "subjects": [ "35R02", "35Q55", "81Q35", "35Q40", "49J40" ], "keywords": [ "noncompact metric graphs", "metric features", "localized nonlinearity", "critical nls", "ground states" ], "note": { "typesetting": "TeX", "pages": 22, "language": "en", "license": "arXiv", "status": "editable" } } }