Spectral gap of generalized MIT bag models

We study some spectral properties of generalized MIT bag models. These are a family of Dirac operators $\{H_\tau\}_{\tau \in \mathbb R\cup \{-\infty, +\infty\}}$ used in the field of relativistic quantum mechanics to model confinement of quarks in hadrons, and their energies are related with the spe...

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Detalles Bibliográficos
Autor: Duran Lamiel, Joaquim|||0009-0002-0586-7589
Tipo de recurso: tesis de maestría
Fecha de publicación:2024
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/400748
Acceso en línea:https://hdl.handle.net/2117/400748
Access Level:acceso abierto
Palabra clave:Spectral theory (Mathematics)
Quantum theory
Dirac operator
spectral theory
MIT bag model
shape optimization
resolvent convergence.
Teoria espectral (Matemàtica)
Quàntums, Teoria dels
Classificació AMS::35 Partial differential equations::35P Spectral theory and eigenvalue problems for partial differential operators
Classificació AMS::35 Partial differential equations::35Q Equations of mathematical physics and other areas of application
Classificació AMS::47 Operator theory::47A General theory of linear operators
Classificació AMS::81 Quantum theory::81Q General mathematical topics and methods in quantum theory
Àrees temàtiques de la UPC::Matemàtiques i estadística::Equacions diferencials i integrals
Descripción
Sumario:We study some spectral properties of generalized MIT bag models. These are a family of Dirac operators $\{H_\tau\}_{\tau \in \mathbb R\cup \{-\infty, +\infty\}}$ used in the field of relativistic quantum mechanics to model confinement of quarks in hadrons, and their energies are related with the spectra of such operators. Their lowest positive eigenvalue is of special interest, and in \cite{Mas2022} it was conjectured that it is minimal for a ball among all domains of the same volume. In this work we prove that the conjecture holds true for corona domains of relatively small hole. Moreover, motivated by some open questions presented in \cite{Mas2022}, in this work we also study the convergence in several resolvent senses of $H_\tau$ as $\tau$ varies. More specifically, we show strong resolvent convergence of $H_\tau$ to $H_{\pm \infty}$ as $\tau \to \pm \infty$, we justify that one cannot improve this to norm resolvent convergence as $\tau \to \pm \infty$, and we show norm resolvent convergence of $H_\tau$ to $H_{\tau_0}$ as $\tau \to \tau_0$, for $\tau_0\in \mathbb R$. These results are new and will be sent for publication in an indexed journal.