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Titre : Quelques problËmes en relativité et cosmologie : Théorie d’einstein-cartan comme alternative au problème de la matière sombre, théorie F(R) et transformation de Lorentz à l’échelle macroscopique Type de document : texte imprimé Auteurs : Amine Benachour, Auteur ; Sami Ryad Zouzou, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2018 Importance : 98 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
PhysiqueTags : Einstein-Cartan theory Spherical symmetry Exact solutions Mass formula Dark matter f(R) theory Ricci scalar Common solutions Lorentz transformation Length contraction Thought experiment Tape measure Simultaneity Macroscopic scale Théorie d’Einstein-Cartan Symétrie sphérique Solutions exactes Formule de masse Matière sombre Théorie f(R) Scalaire de Ricci Solutions communes Transformation de Lorentz Contraction des longueurs Expérience de pensée Mètre ruban Simultanéité Echelle macroscopique نظرية أينشتاين كارتن تناظر كروي حلول المعادلات قانون الكتلة المادة المظلمة نظرية f(R) ثابت الانحناء حلول مشتركة تحويل لورنز تقلص الأطوال تجربة فكرية شريط قياس تزامن مقياس عيانى Index. décimale : 530 Physique Résumé : Some current issues in cosmology lead us to consider theories of gravitation other than general relativity. It is in this context that this thesis is being taken by considering first the Einstein-Cartan theory for static and spherically symmetric spacetime where obtaining exact solutions has led to a general formula linking the internal mass of an object with spherical symmetry to its external mass, highlighting a difference in mass that would likely to provide an explanation for the dark matter problem in the universe. Another theory of gravitation which has been studied in this thesis often proposed as an alternative to the problem of dark energy; is the f(R) theory where the emphasis has been placed on its close link with general relativity by demonstrating the necessary and sufficient condition for a metric to be a solution of the two theories; whose consequences made possible the construction of f(R) theories equivalent to general relativity for a specific form of the Ricci scalar; and set the conditions on the parameters of a given model to have such equivalence. Finally, following the analysis of a thought experiment involving the measurement of the distance between two observers in motion by a tape measure, certain problems related to the application of the Lorentz transformation at the macroscopic scale have also been investigated and solved. Diplôme : Doctorat en sciences En ligne : ../theses/physique/BEN7376.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=11025 Quelques problËmes en relativité et cosmologie : Théorie d’einstein-cartan comme alternative au problème de la matière sombre, théorie F(R) et transformation de Lorentz à l’échelle macroscopique [texte imprimé] / Amine Benachour, Auteur ; Sami Ryad Zouzou, Directeur de thèse . - جامعة الإخوة منتوري قسنطينة, 2018 . - 98 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
PhysiqueTags : Einstein-Cartan theory Spherical symmetry Exact solutions Mass formula Dark matter f(R) theory Ricci scalar Common solutions Lorentz transformation Length contraction Thought experiment Tape measure Simultaneity Macroscopic scale Théorie d’Einstein-Cartan Symétrie sphérique Solutions exactes Formule de masse Matière sombre Théorie f(R) Scalaire de Ricci Solutions communes Transformation de Lorentz Contraction des longueurs Expérience de pensée Mètre ruban Simultanéité Echelle macroscopique نظرية أينشتاين كارتن تناظر كروي حلول المعادلات قانون الكتلة المادة المظلمة نظرية f(R) ثابت الانحناء حلول مشتركة تحويل لورنز تقلص الأطوال تجربة فكرية شريط قياس تزامن مقياس عيانى Index. décimale : 530 Physique Résumé : Some current issues in cosmology lead us to consider theories of gravitation other than general relativity. It is in this context that this thesis is being taken by considering first the Einstein-Cartan theory for static and spherically symmetric spacetime where obtaining exact solutions has led to a general formula linking the internal mass of an object with spherical symmetry to its external mass, highlighting a difference in mass that would likely to provide an explanation for the dark matter problem in the universe. Another theory of gravitation which has been studied in this thesis often proposed as an alternative to the problem of dark energy; is the f(R) theory where the emphasis has been placed on its close link with general relativity by demonstrating the necessary and sufficient condition for a metric to be a solution of the two theories; whose consequences made possible the construction of f(R) theories equivalent to general relativity for a specific form of the Ricci scalar; and set the conditions on the parameters of a given model to have such equivalence. Finally, following the analysis of a thought experiment involving the measurement of the distance between two observers in motion by a tape measure, certain problems related to the application of the Lorentz transformation at the macroscopic scale have also been investigated and solved. Diplôme : Doctorat en sciences En ligne : ../theses/physique/BEN7376.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=11025 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité BEN/7376 BEN/7376 Thèse Bibliothèque principale Thèses Disponible الدراسة الديناميكية لنموذج الطاقة المظلمة اللزجة في الكوسمولوجيا الكلاسيكية و الجاذبية الكوانتية الحلقية. / سارة بن الشيخ
Titre : الدراسة الديناميكية لنموذج الطاقة المظلمة اللزجة في الكوسمولوجيا الكلاسيكية و الجاذبية الكوانتية الحلقية. Type de document : texte imprimé Auteurs : سارة بن الشيخ, Auteur ; نور الدين مباركي, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2018 Importance : 118 ورقة. Format : 30 سم. Note générale : 2نسخ موجودة مكتبة المركزية
Langues : Arabe (ara) Catégories : Arabe
الفيزياءTags : للزوجة السائبة الجاذبية الحلقية الكمية الطاقة المظلمة المادة المظلمة Bulk Viscosity Loop Quantum Gravity Dark Energy Dark matter seconde viscosité gravité quantique des boucles énergie sombre matière sombre Index. décimale : 530 الفيزياء Résumé : In this thesis we have suggested two cosmological models.in the first one we have studied the dynamical behaviors and stability properties of a flat space FRW universe filled with pressureless dark matter and viscous dark energy in the context of standard classical and loop quantum cosmology. Assuming that the dark energy has a constant bulk viscosity, it is found that the bulk viscosity
effects influence only the quintessence model case leading to the existence of a viscous late time attractor solution of de-Sitter type, whereas, the quantum geometry effects influence the phantom model case where the big rip singularity is removed. Moreover, compared with the more recent data, our results of the Hubble parameter as a function of the redshift are in a good agreement. However, in the second model we have studied the dynamical behaviors and stability properties of a flat space FRW universe filled with pressureless dark matter and viscous dark energy in the context of loop
quantum cosmology. Assuming that the dark energy has bulk viscosity in the general form, we have found there exists under some appropriate parameters a stable late time viscous dark energy dominated solution of de Sitter type. the problem of future singularity (big rip) will never occur in this scenario.
Diplôme : Doctorat En ligne : ../theses/physique/ABEN4322.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10880 الدراسة الديناميكية لنموذج الطاقة المظلمة اللزجة في الكوسمولوجيا الكلاسيكية و الجاذبية الكوانتية الحلقية. [texte imprimé] / سارة بن الشيخ, Auteur ; نور الدين مباركي, Directeur de thèse . - جامعة الإخوة منتوري قسنطينة, 2018 . - 118 ورقة. ; 30 سم.
2نسخ موجودة مكتبة المركزية
Langues : Arabe (ara)
Catégories : Arabe
الفيزياءTags : للزوجة السائبة الجاذبية الحلقية الكمية الطاقة المظلمة المادة المظلمة Bulk Viscosity Loop Quantum Gravity Dark Energy Dark matter seconde viscosité gravité quantique des boucles énergie sombre matière sombre Index. décimale : 530 الفيزياء Résumé : In this thesis we have suggested two cosmological models.in the first one we have studied the dynamical behaviors and stability properties of a flat space FRW universe filled with pressureless dark matter and viscous dark energy in the context of standard classical and loop quantum cosmology. Assuming that the dark energy has a constant bulk viscosity, it is found that the bulk viscosity
effects influence only the quintessence model case leading to the existence of a viscous late time attractor solution of de-Sitter type, whereas, the quantum geometry effects influence the phantom model case where the big rip singularity is removed. Moreover, compared with the more recent data, our results of the Hubble parameter as a function of the redshift are in a good agreement. However, in the second model we have studied the dynamical behaviors and stability properties of a flat space FRW universe filled with pressureless dark matter and viscous dark energy in the context of loop
quantum cosmology. Assuming that the dark energy has bulk viscosity in the general form, we have found there exists under some appropriate parameters a stable late time viscous dark energy dominated solution of de Sitter type. the problem of future singularity (big rip) will never occur in this scenario.
Diplôme : Doctorat En ligne : ../theses/physique/ABEN4322.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10880 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité بنا/4322 بنا/4322 Thèse Bibliothèque principale Thèses Disponible
