M.Phil / MS
Permanent URI for this collectionhttps://repository.cuilahore.edu.pk/handle/123456789/52
This collection archives the complete set of theses produced by students of the COMSATS University Islamabad, Lahore Campus.
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Item Inflationary Dynamics and Thermodynamics of Chaplygin Gas Models(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2018) Muhammad Adeel Sultan; CIIT/SP17-RMT-006/LHR; Dr. Abdul Jawad; LHR TP 5441In this thesis, we study the reconstruction of warm inflation model with the help of tensor to scalar ratio (r) and scalar spectral index (ns) in terms of number of e-folds (N). In this regards, we take flat FRW metric and discuss the general forms of dissipative coefficient Γ(φ, T ) as well as effec- tive potential V (φ, T ) for two dissipative regimes i.e., the weak and strong. We use inflationary parameters like slow roll parameters, power spectrum of the curvature perturbation, tensor spectrum, spectral index, scalar to tensor ratio and Hubble parameter to find the generalized form of dissi- pative coefficient and effective potential. Further, we discuss generalized cosmic Chaplygin gas in the scenario of particle creation. We examine energy density (ρ), Hubble parameter (H), declaration parameter (q), tem- perature (T ) and particle number density (n) under three different models of particle creation rate. We also analyze the production of entropy and Bekenstein entropy in the scenario of first law of thermodynamics. We dis- cuss the validity of generalized second law of thermodynamics and thermal equilibrium under three models of Γ and discuss the graphical behavior of above mentioned terms.Item Generalized Chaplygin Gas Traversable Wormhole Solutions by Using GUP Corrected Casimir Energy(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2020) Ubaid Ur Rehman; SP19-RMT-019; LHR TP 6477; Dr. Abdul JawadIn this thesis, we explore the wormhole solutions (which are initially pro- sed by Garattoni (Eur. Phys. J. C 79(2019)951) who take generalized certainty principle (GUP) with Casimir energy) in the framework of two ll-known dark energy models, generalized Chaplygin gas and polytropic s. We consider the GUP corrected pressure (force per unit surface area) the equation of state of these dark energy models to construct the gener- zed Chaplygin gas corrected energy density and polytropic gas corrected ergy density. Three models of redshift function are taken into account construct shape function as well as wormhole geometry for both cases corrected energy densities. We find the behavior of some parameters ough equation of state, energy conditions (null, weak and strong) at the oat of the wormhole with radius r0.