A SECOND COUNTER-EXAMPLE FOR SHEAR-FREE PERFECT FLUID CONJECTURE IN F(R,T) GRAVITY

Abstract

In this study, to find the second counter-example for shear-free perfect fluid conjecture in modified gravitation theories and to investigate whether similar solutions are valid for all Bianchi type metrics in f(R,T) gravity; spatially homogeneous and anisotropic, shear-free, rotating and expanding Bianchi type-II and V models have been considered in context of f(R,T) theory of gravity. An exact solution has been obtained, functional form of f(R,T) function has been reconstructed for Bianchi type-II model and it has been shown that the matter-energy content of such a universe is stiff fluid. It has also been shown that Bianchi type-V model filled with a shear-free perfect fluid cannot rotate and expand simultaneously

Keywords

• Rotation, Expansion, Shear-free, Perfect fluid, Bianchi type-II Model, Bianchi Type-V Model

F(R,T) GRAVİTEDE MAKASLAMASIZ MÜKEMMEL AKIŞKAN İDDİASINA İKİNCİ BİR KARŞIT ÖRNEK

Abstract

Bu çalışmada, değiştirilmiş gravitasyon teorilerinde makaslamasız mükemmel akışkan iddiasına ikinci bir karşıt-örnek bulmak ve benzer çözümlerin f(R,T) gravitede tüm Bianchi tip metrikler için geçerli olup olmadığını incelemek amacıyla, f(R,T) gravitasyon teorisi çerçevesinde, uzayca homojen, eşyönsüz, makaslamasız, dönen ve genişleyen Bianchi tip-II ve V modelleri göz önüne alınmıştır. Bianchi tip-II modeli için kesin bir çözüm elde edilmiş, f(R,T) fonksiyonunun fonksiyonel formu inşa edilmiş ve böyle bir evrenin madde-enerji içeriğinin katı akışkan olduğu gösterilmiştir. Makaslamasız bir mükemmel akışkanla dolu Bianchi tip-V modelinin ise, aynı anda hem dönme ve hem de genişlemeye sahip olamayacağı gösterilmiştir

Keywords

• Dönme, Genişleme, Makaslamasız, Mükemmel Akışkan, Bianci tip-II

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