Narrow Results

This work analyzes the dynamical variables and information transfer of a collapsing string fluid in the theory of Rainbow gravity (RG). Modifications are made to the field equations for the anisotropic string fluid in spherical geometry with the necessary rainbow functions. We have calculated the radius and time when effective horizons formed. This calculation helps to estimate the time of the observer reaching the apparent horizon. Moreover, we have computed the dynamical variables concerning the string fluid including mass density, pressure and the string tension. The behavior of the dynamical quantities is presented graphically. It is found that the rainbow parameter $\eta$ affects the dynamical variables. The results enable us to understand the physics of a collapsing fluid and the information transfer in the collapsing scenario.

We study the consequences of the existence of spacelike conformal Killing vectors (SpCKV) parallel to x^a for cosmic strings and string fluid in the context of general relativity. The inheritance symmetries of the cosmic strings and string fluid are discussed in the case of SpCKV. Furthermore we examine proper homothetic spacelike Killing vectors for the cosmic strings and string fluid.

We discuss the spherical collapse of a two fluid system: a string fluid and a null fluid described by a generalized Vaidya metric. This led us to explicitly describe the effect of a string fluid on the established picture of a null fluid collapse (Vaidya collapse). It is found that there is a shrinkage of the initial data space for naked singularities of Vaidya collapse upon taking into account a string fluid. The implications of the results in the context of the cosmic censorship conjecture are discussed.

This study investigated the formation and evolution of a strange star known as SAX.J1808.4–3658 in the Krori–Barua Rainbow spacetime, resulting from the collapse of string fluid. The study examined the dynamical variables derived from the field equations, taking into consideration the influence of the particle’s energy on the mass density, pressure, and string tension. Additionally, various techniques were employed to analyze the physical properties, including gradients, energy conditions, anisotropy, stability, the Tolman–Oppenheimer–Volkoff equation, mass function, compactness, and red-shift. The study’s findings revealed that the strange star SAX.J1808.4–3658 satisfies all the conditions necessary for its evolution from an anisotropic string fluid. This discovery suggests that strange stars might have emerged during the string-oriented quark era of the Universe. The researchers presented all the physical quantities within the frameworks of both rainbow gravity and general relativity, while also utilizing graphical representations to aid in comprehending the study’s findings. The energy conditions and anisotropy were found to be fulfilled, indicating the stability of the strange star. Furthermore, the Tolman–Oppenheimer–Volkoff equation was employed to determine the maximum mass of the strange star, which was found to align with observational data.