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dc.contributor.advisorMiller, Bruce N.
dc.contributor.authorOCallaghan, Mark Charlesen_US
dc.date.accessioned2016-05-12T21:06:56Z
dc.date.available2016-05-12T21:06:56Z
dc.date.created2016en_US
dc.date.issued2016en_US
dc.identifiercat-002764575
dc.identifier.urihttps://repository.tcu.edu/handle/116099117/10946
dc.description.abstractExperimental measurements of the lifetime of positrons and positronium and the mobility of electrons show dramatic changes when the host fluid is in the vicinity of the liquid-vapor critical point. Since the compressibility diverges at the critical point, we understand that a low-mass quantum particle (qp) disturbs the local fluid density and stabilizes in a mesoscopic droplet or bubble. We refer to this phenomenon as ?self-trapping?. Theoretical formulations of self-trapping have taken two different routes: mean field theory where the Schrodinger equation governing the qp is solved in the averaged local potential produced by the fluid bubble or droplet, or path integral Monte Carlo (PIMC) where the qp is represented by an imaginary time Feynman-Kac path integral interacting with the (classical) fluid molecules. While the complete range of fluctuations is taken into account by PIMC, convergence is prohibitively difficult to obtain. A primitive model of a fluid with a critical point that can be conveniently modeled is provided by the two-dimensional lattice gas. To explore self-trapping in a lattice gas, in this dissertation PIMC was reformulated for a quantum particle that lives on a lattice and interacts with the coexisting ?atoms?. To test the viability of the formulation, the predictions of the lattice PIMC were compared with two analytically solvable, one-dimensional, quenched models. Finally it was shown that the fully annealed hybrid, two-dimensional lattice gas-qp system exhibits the phenomena of self-trapping and captures the essential features of the experimental measurements.--Abstract.
dc.format.mediumFormat: Onlineen_US
dc.language.isoengen_US
dc.publisher[Fort Worth, Tex.] : Texas Christian University,en_US
dc.relation.ispartofTexas Christian University dissertationen_US
dc.relation.ispartofUMI thesis.en_US
dc.relation.ispartofTexas Christian University dissertation.en_US
dc.relation.requiresMode of access: World Wide Web.en_US
dc.relation.requiresSystem requirements: Adobe Acrobat reader.en_US
dc.subject.lcshPath integrals.en_US
dc.subject.lcshMonte Carlo method.en_US
dc.subject.lcshLattice gas.en_US
dc.titlePath integral Monte Carlo on a latticeen_US
dc.typeTexten_US
etd.degree.departmentDepartment of Physics and Astronomy
etd.degree.levelDoctoral
local.collegeCollege of Science and Engineering
local.departmentPhysics and Astronomy
local.academicunitDepartment of Physics and Astronomy
dc.type.genreDissertation
local.subjectareaPhysics and Astronomy
etd.degree.nameDoctor of Philosophy
etd.degree.grantorTexas Christian University


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