ABSTRACT CONSERVED CHARGES IN ASYMPTOTICALLY (ANTI)-DE SITTER SPACETIME G&Uuml / LL&Uuml / , iBRAHiM M.S., Department of Physics Supervisor: Assoc. Prof. Dr. Bayram Tekin August 2005, 77 pages. In this master&rsquo / s thesis, the Killing vectors are introduced and the Killing equation is derived. Also, some information is given about the cosmological constant. Then, the Abbott-Deser (AD) energy is reformulated by linearizing the Einstein equation with cosmological constant. From the linearized Einstein equation, Killing charges are derived by using the properties of Killing vectors. Using this formulation, energy is calculated for some specific cases by using the Schwarzschild-de Sitter metric. Last, the Einstein-Gauss-Bonnet model is studied. The equations of motion are calculated by solving the generic action at quadratic order. Following this, all energy calculations are renewed for this model. Some useful relations and calculations are shown in Appendix (A-B) parts. &Ouml / Z ASiMPTOTiK (ANTi)-DE SITTER UZAYZAMANINDA KORUNAN Y&Uuml / KLER G&Uuml / LL&Uuml / , iBRAHiM Y&uuml / ksek Lisans, Fizik B&ouml / l&uuml / m&uuml / Tez Y&ouml / neticisi: Assoc. Prof. Dr. Bayram Tekin Agustos 2005, 77 sayfa. Bu master &ccedil / aliSmasinda, Killing vekt&ouml / rler tanimlandi ve Killing denklemi &ccedil / ikarildi. Ayrica evrenbilimsel sabit, de-Sitter ve Anti-de Sitter uzaylari hakkinda bilgi verildi. Sonra, Abbott-Deser (AD) enerjisi, evrenbilimsel sabitli Einstein denklemi dogrusallaStirilarak yeniden form&uuml / le edildi. DogrusallaStirilmiS Einstein denkleminden, Killing vekt&ouml / rlerin &ouml / zellikleri kullanilarak Killing y&uuml / kleri (Deser-Tekin denklemi) &ccedil / ikarildi. Schwarzschild-de Sitter metrigi kullanilarak &ouml / zel durumlar i&ccedil / in enerji hesaplandi. Son olarak Einstein-Gauss-Bonnet (GB) modeli &ccedil / aliSildi. ikinci dereceden genel eylem &ccedil / &ouml / z&uuml / lerek hareket denklemleri hesaplandi. Bundan sonra, t&uuml / m enerji hesaplamalari bu model i&ccedil / in tekrarlandi. Bazi faydali hesaplamalar ek (A-B) kisimlarinda g&ouml / sterilmiStir.