Perturbation analysis of fluctuations in the universe on large scales, including decaying solutions and rotational velocities

On small scales, the universe is inhomogeneous. However, on scales many times greater than the average distances between galaxies, the distribution of galaxies, galaxy clusters, and dark matter begins to look more uniform throughout the universe. This study aims to analyze the large-scale structure of matter in the universe by looking at the time evolution and spatial development of the linear perturbations to the average density and average velocity of matter in the universe. These linear perturbations convey information about structure formation and distribution in the cosmos. In particular, this research investigates how retaining decaying terms and rotational velocities in the calculations ( which are often ignored to facilitate the mathematics) affects the higher order terms in the density and velocity perturbations for a matter-dominated universe. On such large scales, the matter in the universe is assumed to behave like a pressure-less fluid permeating the cosmos. The gravitational instability model and the Newtonian fluid flow equations are used as bases for analyzing the density and velocity perturbations. So far, results show that retaining decaying terms and rotational velocities when solving for the density and velocity perturbations produces possibly significant terms that are otherwise overlooked. In the next step of this project, the statistics describing the spatial distribution of the density and velocity perturbations, in particular the two-point correlation functions, will be calculated and investigated

Numerical Modeling of The 2009 Impact Event On Jupiter

We have investigated the 2009 July impact event on Jupiter using the ZEUS-MP 2 three-dimensional hydrodynamics code. We studied the impact itself and the following plume development. Eight impactors were considered: 0.5 km and 1 km porous (rho = 1.760 g cm (3)) and non-porous (rho = 2.700 g cm (3)) basalt impactors, and 0.5 km and 1 km porous (rho = 0.600 g cm(-3)) and non-porous (rho = 0.917 g cm(-3)) ice impactors. The simulations consisted of these bolides colliding with Jupiter at an incident angle of theta = 69 degrees from the vertical and with an impact velocity of v = 61.4 km s(-1). Our simulations show the development of relatively larger, faster plumes created after impacts involving 1 km diameter bodies. Comparing simulations of the 2009 event with simulations of the Shoemaker-Levy 9 (SL9) events reveals a difference in plume development, with the higher incident angle of the 2009 impact leading to a shallower terminal depth and a smaller and slower plume. We also studied the amount of dynamical chaos present in the simulations conducted at the 2009 incident angle. Compared to the chaos of the SL9 simulations, where theta approximate to 45 degrees, we find no significant difference in chaos at the higher 2009 incident angle

NUMERICAL MODELING OF THE 2009 IMPACT EVENT ON JUPITER

We have investigated the 2009 July impact event on Jupiter using the ZEUS-MP 2 three-dimensional hydrodynamics code. We studied the impact itself and the following plume development. Eight impactors were considered: 0.5 km and 1 km porous (\rho = 1.760 g cm^{-3}) and non-porous (\rho = 2.700 g cm^{-3}) basalt impactors, and 0.5 km and 1 km porous (\rho = 0.600 g cm^{-3}) and non-porous \rho = 0.917 g cm^{-3}) ice impactors. The simulations consisted of these bolides colliding with Jupiter at an incident angle of \theta = 69 degrees from the vertical and with an impact velocity of v = 61.4 km s^{-1}. Our simulations show the development of relatively larger, faster plumes created after impacts involving 1 km diameter bodies. Comparing simulations of the 2009 event with simulations of the Shoemaker-Levy 9 events reveals a difference in plume development, with the higher incident angle of the 2009 impact leading to a shallower terminal depth and a smaller and slower plume. We also studied the amount of dynamical chaos present in the simulations conducted at the 2009 incident angle. Compared to the chaos of the SL9 simulations, where \theta is approximately 45 degrees, we find no significant difference in chaos at the higher 2009 incident angle.Comment: 8 pages, 7 figure