{"id":{"repo_id":"buffalo","oai_identifier":"oai:ubir.buffalo.edu:10477/80907"},"canonical_url":"https://search.dev.ndltd.org/etd/buffalo/oai:ubir.buffalo.edu:10477/80907","repository":{"repo_id":"buffalo","name":"Buffalo","base_url":"https://ubir.buffalo.edu/oai/request"},"display":{"title":"Quantum Effects in Weak and Strong Gravity Regimes","abstract":"Ph.D.","abstract_html":"Ph.D.","abstract_has_math":false,"creators":["Saini, Anshul"],"institution":"State University of New York at Buffalo","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":["Stojkovic, Dejan","Physics"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2019,"date_issued":"2019-10-29T16:48:02Z","date_published":"2019-10-29T16:48:02Z","updated_at":"2026-07-27T19:05:25Z","subjects":["physics"],"languages":["eng"],"rights":["Users of works found in University at Buffalo Institutional Repository (UBIR) are responsible for identifying and contacting the copyright owner for permission to reuse. University at Buffalo Libraries do not manage rights for copyright-protected works and cannot assist with permissions.","Copyright retained by author."],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/10477/80907","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Stojkovic, Dejan","Physics"]},{"key":"dc:creator","label":"Author","values":["Saini, Anshul"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2019-10-29T16:48:02Z","2019","2019-08-07 15:32:38"]},{"key":"dc:publisher","label":"Institution","values":["State University of New York at Buffalo"]},{"key":"dc:type","label":"Dc Type","values":["Text","Dissertation"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["physics"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["Users of works found in University at Buffalo Institutional Repository (UBIR) are responsible for identifying and contacting the copyright owner for permission to reuse. University at Buffalo Libraries do not manage rights for copyright-protected works and cannot assist with permissions.","Copyright retained by author."]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://hdl.handle.net/10477/80907"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Ph.D.","We investigated a quantum gravitational collapse and the radiation emitted in the process, using the Schrodinger wave functional formalism to understand the time evolution of the system. We studied the final stages of the gravitational collapse to capture quantum effects in the near singularity limit and found that the equations of motion which govern the behavior of the collapsing shell near the classical singularity become strongly non-local. The wavefunction and the corresponding probability density were non-singular at the origin, thus indicating that quantization is able to rid gravity of singularities. The process of gravitational collapse excites the fields propagating in the background geometry and gives rise to thermal radiation. We studied time-dependent Hawking-like radiation emitted during the gravitational collapse of a thin shell as seen by asymptotic and infalling observers. Importantly, we demonstrated by explicit calculations that the density matrix corresponding to such radiation describes a pure state. While Hawking’s leading order density matrix contains only the diagonal terms, we calculated the off-diagonal correlation terms. These correlations start very small, but grow in time and significantly modify the density matrix. Importantly, we found that in contrast to the trace of the Hawking’s density matrix squared, which decreases during the evolution, the trace of the total density matrix squared remains unity at all times and all frequencies, implying that the process of radiation from a collapsing object is unitary. In addition, we extended our analysis to 2+1 and 3+1 dimensional gravity with Anti-de Sitter asymptotics and arrived at the same conclusions, further proving the reliability of Schrodinger wave functional formalism. According to the hoop conjecture, if we localize two particles within the Schwarzschild radius corresponding to their center of mass-energy, then a black hole will form. We also generalized the hoop conjecture to expanding spacetimes and found that it crucially depends on the expansion rate of the background space. Finally, we calculated the number density, energy density and production rate of black holes produced by the collision of particles. Interestingly, we found that although black holes may be numerous at high temperatures, they never dominate over the background radiation below the Planck temperature."]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Quantum Effects in Weak and Strong Gravity Regimes"]}]}],"canonical_facts":{"dc:contributor":["Stojkovic, Dejan","Physics"],"dc:creator":["Saini, Anshul"],"dc:date":["2019-10-29T16:48:02Z","2019","2019-08-07 15:32:38"],"dc:description":["Ph.D.","We investigated a quantum gravitational collapse and the radiation emitted in the process, using the Schrodinger wave functional formalism to understand the time evolution of the system. We studied the final stages of the gravitational collapse to capture quantum effects in the near singularity limit and found that the equations of motion which govern the behavior of the collapsing shell near the classical singularity become strongly non-local. The wavefunction and the corresponding probability density were non-singular at the origin, thus indicating that quantization is able to rid gravity of singularities. The process of gravitational collapse excites the fields propagating in the background geometry and gives rise to thermal radiation. We studied time-dependent Hawking-like radiation emitted during the gravitational collapse of a thin shell as seen by asymptotic and infalling observers. Importantly, we demonstrated by explicit calculations that the density matrix corresponding to such radiation describes a pure state. While Hawking’s leading order density matrix contains only the diagonal terms, we calculated the off-diagonal correlation terms. These correlations start very small, but grow in time and significantly modify the density matrix. Importantly, we found that in contrast to the trace of the Hawking’s density matrix squared, which decreases during the evolution, the trace of the total density matrix squared remains unity at all times and all frequencies, implying that the process of radiation from a collapsing object is unitary. In addition, we extended our analysis to 2+1 and 3+1 dimensional gravity with Anti-de Sitter asymptotics and arrived at the same conclusions, further proving the reliability of Schrodinger wave functional formalism. According to the hoop conjecture, if we localize two particles within the Schwarzschild radius corresponding to their center of mass-energy, then a black hole will form. We also generalized the hoop conjecture to expanding spacetimes and found that it crucially depends on the expansion rate of the background space. Finally, we calculated the number density, energy density and production rate of black holes produced by the collision of particles. Interestingly, we found that although black holes may be numerous at high temperatures, they never dominate over the background radiation below the Planck temperature."],"dc:format":["application/pdf"],"dc:identifier":["http://hdl.handle.net/10477/80907"],"dc:language":["eng"],"dc:publisher":["State University of New York at Buffalo"],"dc:rights":["Users of works found in University at Buffalo Institutional Repository (UBIR) are responsible for identifying and contacting the copyright owner for permission to reuse. University at Buffalo Libraries do not manage rights for copyright-protected works and cannot assist with permissions.","Copyright retained by author."],"dc:subject":["physics"],"dc:title":["Quantum Effects in Weak and Strong Gravity Regimes"],"dc:type":["Text","Dissertation"]},"updated_at":"2026-07-27T19:05:25Z"}