Studies on Modified Newtonian Dynamics and Dark Matter için kapak resmi
Studies on Modified Newtonian Dynamics and Dark Matter
Başlık:
Studies on Modified Newtonian Dynamics and Dark Matter
Yazar:
Karahan, Canan Nurhan, author.
Fiziksel Tanımlama:
xi, 96 leaves: illustrarions, charts;+ 1 computer laser optical disc.
Özet:
The flat rotation curves of the galaxies are considered to be anomalous observations according to Newtonian dynamics. There are two dierent approaches to explain this challenge - Dark Matter (DM) and Modified Newtonian Dynamics (MOND). Both of them possess some failures as well as many successes. Beyond these failures, they have much more fundamental diculties such as the lack of any direct or indirect detection of proposed dark matter candidates and the lack of a full-fledged relativistic version of MOND theory. In this thesis, focus will be on these fundamental problems. First, the relativistic MOND theory will be studied. The first successful relativistic version is Tensor-Vector-Scalar (TeVeS) theory based on bimetric gravity. However, the addition of vector and scalar fields into the theory by hand is not much dierent than the addition of dark matter. In this study, TeVeS theory will be constructed in a more natural way. To do this, at first standard Einstein-Hilbert action will be extended by using non-Riemannian structures (torsion, non-metricity, etc.) from metric-ane formalism. It will then be shown that obtained extended theory of gravity could turn into a Tensor- Vector-Scalar theory via decomposition of ane connection as Levi-Civita connection and rank(1,2) tensorial structure composed of lower rank fundamental and composite fields such as vector and scalar fields. Subsequently, it will be continued with a study on the relativistic MOND theory, without requiring an action principle. In this study, energy momentum tensor part will be modified rather than the geometrical part of the Einstein field equations. This could be considered as the first dynamical approach to relativistic MOND in the literature. It will be shown that the modified field equations obtained via this dynamical approach can be reduced to true MONDian force in the non-relativistic limit in some astrophysical domains. This study can be also considered as an extension of Milgrom’s modified inertia approach to relativistic domain. Finally, a new phenomenological model- Higgsed Stueckelberg scenario - involving a hidden vector field with an accompanying scalar field ensuring the gauge invariance will be proposed. It will be shown that the contributions from the hidden fields could stabilize the Higgs boson mass at one-loop, where the set up can accommodate naturally a viable DM candidate.
Yazar Ek Girişi:
Tek Biçim Eser Adı:
Thesis (Doctoral)--İzmir Institute of Technology: Physics.

İzmir Institute of Technology: Physics--Thesis (Doctoral).
Elektronik Erişim:
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