{"title":"An anisotropic cosmological model with Bianchi type III universe in f(G) gravity","authors":"Nihir Basumatary, M. Dewri","doi":"10.53894/ijirss.v7i2.2890","DOIUrl":null,"url":null,"abstract":"The paper is devoted to exploring the exact solution of the modified Einstein's field in the setting of spatially homogeneous and anisotropic Bianchi type III spacetime in modified f(G) gravity, where G is Gauss-Bonnet invariant. Here, by employing the hyperbolic hybrid scale factor a = emt (sinh(t))n in which m,n are positive constants, with the power-law f (G)=βGm+1 model where β,m are arbitrary constants, we computed the physical and geometrical properties of the cosmological parameters of the model. The results of the model parameters are well satisfied with recent cosmological observational data. To get the exact solution of the field equation of the Bianchi type III model in the presence of an anisotropic dark fluid, we consider the relation in which the shear scalar (σ) is proportional to the expansion scalar (θ), resulting in C = An. Furthermore, the energy conditions for the power-law f(G) model are graphically examined, and it turns out that the null energy condition (NEC), weak energy condition (WEC), and dominant energy condition (DEC) are well satisfied except for the strong energy condition (SEC). The violation of the strong energy conditions (SEC) indicates the f(G) model supports the universe's current expansion with negative pressure, having a quintessence model in the present and Λ cold dark matter (CDM) model in the future.","PeriodicalId":282613,"journal":{"name":"International Journal of Innovative Research and Scientific Studies","volume":"21 2","pages":""},"PeriodicalIF":0.0000,"publicationDate":"2024-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"International Journal of Innovative Research and Scientific Studies","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.53894/ijirss.v7i2.2890","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0
Abstract
The paper is devoted to exploring the exact solution of the modified Einstein's field in the setting of spatially homogeneous and anisotropic Bianchi type III spacetime in modified f(G) gravity, where G is Gauss-Bonnet invariant. Here, by employing the hyperbolic hybrid scale factor a = emt (sinh(t))n in which m,n are positive constants, with the power-law f (G)=βGm+1 model where β,m are arbitrary constants, we computed the physical and geometrical properties of the cosmological parameters of the model. The results of the model parameters are well satisfied with recent cosmological observational data. To get the exact solution of the field equation of the Bianchi type III model in the presence of an anisotropic dark fluid, we consider the relation in which the shear scalar (σ) is proportional to the expansion scalar (θ), resulting in C = An. Furthermore, the energy conditions for the power-law f(G) model are graphically examined, and it turns out that the null energy condition (NEC), weak energy condition (WEC), and dominant energy condition (DEC) are well satisfied except for the strong energy condition (SEC). The violation of the strong energy conditions (SEC) indicates the f(G) model supports the universe's current expansion with negative pressure, having a quintessence model in the present and Λ cold dark matter (CDM) model in the future.
本文致力于探索修正 f(G) 引力下空间均匀和各向异性比安奇 III 型时空中修正爱因斯坦场的精确解,其中 G 为高斯-波奈不变式。在这里,我们利用双曲混合尺度因子 a = emt (sinh(t))n (其中 m,n 为正常数)和幂律 f (G)=βGm+1 模型(其中 β,m 为任意常数),计算了模型宇宙学参数的物理和几何特性。模型参数的计算结果与最近的宇宙学观测数据十分吻合。为了得到存在各向异性暗流体的比安奇 III 型模型场方程的精确解,我们考虑了剪切标量(σ)与膨胀标量(θ)成正比的关系,结果是 C = An。此外,对幂律 f(G) 模型的能量条件进行了图解检验,结果发现除了强能量条件(SEC)之外,空能量条件(NEC)、弱能量条件(WEC)和主导能量条件(DEC)都得到了很好的满足。对强能量条件(SEC)的违反表明,f(G)模型支持宇宙目前的负压膨胀,现在是五元模型,未来是Λ冷暗物质(CDM)模型。