{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/77195"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/77195","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Semiclassical Methods in Field Theories: The Use of Soliton and Instanton","abstract":"The first part of this thesis is to study how solitons interact among themselves in Sine-Gordon system. We translate the information encoded in various known soliton solutions such as scattering time delays and oscillation periods into that of the corresponding quantities in particle dynamics. We examine different points of view for obtaining the interaction potentials. We then quantize the effective potentials and compare the mass spectrum with that obtained from the path integral approximation. The second part of this thesis concerns with the instanton physics in Sigma model and in nonabelian gauge theory. An instanton solution defines a dominant collective coordinate. By considering only the quantum physics along these coordinates (a good approximation in weak coupling limit), we can reduce a complicated field theory problem to a simple Schrodinger type problem. We study the interaction among instantons, examine the dilute gas limit assumption, and compute the vacuum state wave functionals and eigen-energies. We also study the method to generate envelope solutions out of a family of existing instanton solutions.","abstract_html":"The first part of this thesis is to study how solitons interact among themselves in Sine-Gordon system. We translate the information encoded in various known soliton solutions such as scattering time delays and oscillation periods into that of the corresponding quantities in particle dynamics. We examine different points of view for obtaining the interaction potentials. We then quantize the effective potentials and compare the mass spectrum with that obtained from the path integral approximation. The second part of this thesis concerns with the instanton physics in Sigma model and in nonabelian gauge theory. An instanton solution defines a dominant collective coordinate. By considering only the quantum physics along these coordinates (a good approximation in weak coupling limit), we can reduce a complicated field theory problem to a simple Schrodinger type problem. We study the interaction among instantons, examine the dilute gas limit assumption, and compute the vacuum state wave functionals and eigen-energies. We also study the method to generate envelope solutions out of a family of existing instanton solutions.","abstract_has_math":false,"creators":["Hsu, Yupai"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Physics","degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2015,"date_issued":"2015-05-13T15:22:23Z","date_published":"2015-05-13T15:22:23Z","updated_at":"2026-07-22T22:26:10Z","subjects":["Physics, Elementary Particles and High Energy"],"languages":["eng"],"rights":[],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["(UMI)AAI8108546"],"render_values":[{"text":"(UMI)AAI8108546","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/77195","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Hsu, Yupai"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2015-05-13T15:22:23Z","10000-01-01","1980"]},{"key":"dc:type","label":"Dc Type","values":["text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Physics"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Dissertation"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph.D."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Illinois at Urbana-Champaign"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Physics, Elementary Particles and High Energy"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["eng"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://hdl.handle.net/2142/77195","(UMI)AAI8108546"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["The first part of this thesis is to study how solitons interact among themselves in Sine-Gordon system. We translate the information encoded in various known soliton solutions such as scattering time delays and oscillation periods into that of the corresponding quantities in particle dynamics. We examine different points of view for obtaining the interaction potentials. We then quantize the effective potentials and compare the mass spectrum with that obtained from the path integral approximation. The second part of this thesis concerns with the instanton physics in Sigma model and in nonabelian gauge theory. An instanton solution defines a dominant collective coordinate. By considering only the quantum physics along these coordinates (a good approximation in weak coupling limit), we can reduce a complicated field theory problem to a simple Schrodinger type problem. We study the interaction among instantons, examine the dilute gas limit assumption, and compute the vacuum state wave functionals and eigen-energies. We also study the method to generate envelope solutions out of a family of existing instanton solutions.","Made available in DSpace on 2015-05-13T15:22:23Z (GMT). No. of bitstreams: 2 license.txt: 4848 bytes, checksum: 96035ab3f5e1c23cc7138a224ce498bd (MD5) 8108546.PDF: 3045319 bytes, checksum: 814bf018814bbc41120a273b60179105 (MD5) Previous issue date: 1980","Embargo set by: Seth Robbins for item 78406 Lift date: Forever Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs","Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs","U of I Only","148 p.","Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1980."]},{"key":"dc:title","label":"Title","values":["Semiclassical Methods in Field Theories: The Use of Soliton and Instanton"]}]}],"canonical_facts":{"dc:creator":["Hsu, Yupai"],"dc:date":["2015-05-13T15:22:23Z","10000-01-01","1980"],"dc:description":["The first part of this thesis is to study how solitons interact among themselves in Sine-Gordon system. We translate the information encoded in various known soliton solutions such as scattering time delays and oscillation periods into that of the corresponding quantities in particle dynamics. We examine different points of view for obtaining the interaction potentials. We then quantize the effective potentials and compare the mass spectrum with that obtained from the path integral approximation. The second part of this thesis concerns with the instanton physics in Sigma model and in nonabelian gauge theory. An instanton solution defines a dominant collective coordinate. By considering only the quantum physics along these coordinates (a good approximation in weak coupling limit), we can reduce a complicated field theory problem to a simple Schrodinger type problem. We study the interaction among instantons, examine the dilute gas limit assumption, and compute the vacuum state wave functionals and eigen-energies. We also study the method to generate envelope solutions out of a family of existing instanton solutions.","Made available in DSpace on 2015-05-13T15:22:23Z (GMT). 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