000096101 001__ 96101 000096101 005__ 20210902121907.0 000096101 0248_ $$2sideral$$a120368 000096101 037__ $$aART-2020-120368 000096101 041__ $$aeng 000096101 100__ $$aAres, Filiberto 000096101 245__ $$aComplex behavior of the density in composite quantum systems 000096101 260__ $$c2020 000096101 5060_ $$aAccess copy available to the general public$$fUnrestricted 000096101 5203_ $$aIn this paper, we study how the probability of presence of a particle is distributed between the two parts of a composite fermionic system. We uncover that the difference of probability depends on the energy in a striking way and show the pattern of this distribution. We discuss the main features of the latter and explain analytically those that we understand. In particular, we prove that it is a nonperturbative property and we find out a large/small coupling constant duality. We also find and study features that may connect our problem with certain aspects of nonlinear classical dynamics, such as the existence of resonances and sensitive dependence on the state of the system. We show that the latter has, indeed, a similar origin than in classical mechanics: the appearance of small denominators in the perturbative series. Inspired by the proof of the Kolmogorov-Arnold-Moser theorem, we are able to deal with this problem by introducing a cutoff in energies that eliminates these small denominators. We also formulate some conjectures that we are not able to prove at present but can be supported by numerical experiments. 000096101 536__ $$9info:eu-repo/grantAgreement/ES/DGA-FSE/E21-17R$$9info:eu-repo/grantAgreement/ES/MINECO-FEDER/PGC2018-095328-B-I00 000096101 540__ $$9info:eu-repo/semantics/openAccess$$aAll rights reserved$$uhttp://www.europeana.eu/rights/rr-f/ 000096101 590__ $$a4.036$$b2020 000096101 591__ $$aMATERIALS SCIENCE, MULTIDISCIPLINARY$$b130 / 333 = 0.39$$c2020$$dQ2$$eT2 000096101 591__ $$aPHYSICS, CONDENSED MATTER$$b22 / 69 = 0.319$$c2020$$dQ2$$eT1 000096101 591__ $$aPHYSICS, APPLIED$$b41 / 160 = 0.256$$c2020$$dQ2$$eT1 000096101 592__ $$a1.78$$b2020 000096101 593__ $$aElectronic, Optical and Magnetic Materials$$c2020$$dQ1 000096101 593__ $$aCondensed Matter Physics$$c2020$$dQ1 000096101 655_4 $$ainfo:eu-repo/semantics/article$$vinfo:eu-repo/semantics/publishedVersion 000096101 700__ $$0(orcid)0000-0001-7715-4970$$aEsteve, José G.$$uUniversidad de Zaragoza 000096101 700__ $$0(orcid)0000-0002-0882-0463$$aFalceto, Fernando$$uUniversidad de Zaragoza 000096101 700__ $$aUsón, Alberto 000096101 7102_ $$12004$$2405$$aUniversidad de Zaragoza$$bDpto. Física Teórica$$cÁrea Física Teórica 000096101 773__ $$g102, 16 (2020), 165121 [13 pp]$$pPhys. Rev. B$$tPHYSICAL REVIEW B$$x2469-9950 000096101 8564_ $$s1327014$$uhttps://zaguan.unizar.es/record/96101/files/texto_completo.pdf$$yVersión publicada 000096101 8564_ $$s535187$$uhttps://zaguan.unizar.es/record/96101/files/texto_completo.jpg?subformat=icon$$xicon$$yVersión publicada 000096101 909CO $$ooai:zaguan.unizar.es:96101$$particulos$$pdriver 000096101 951__ $$a2021-09-02-10:40:22 000096101 980__ $$aARTICLE