Assignment 3 Essay Example | Topics and Well Written Essays - 500 words - 10

Assignment 3 - Essay Example Matters or issues concerning dark energy are normally speculative in nature. The evidence for the existence of the dark energy arises from three major independent sources. Therefore, these sources lead us to our three major hypotheses on dark energy: distance measurements through the red shift, explains the universe has expanded during its last half life; the theoretical requirements for extra energy type that is not matter and dark matter, to form the observationally flat universe; and it can be identified through the large scale measurement of wave patterns with mass density. Dark energy is believed to be homogeneous and not very dense; it interacts with other universal forces; apart for gravitational force. These theories hypothesize formation of galaxies or cluster of galaxies; Cold Dark Matter aspect of cosmology describes that clustering and also merging processes enables galaxies to gain mass and determine shape and structure. One theory explains the ‘top down’ galaxies formation aspect. The disk galaxies are created through monolithic collapse of the large gas cloud. In the process of cloud collapse; gas settles in a highly rotating disk. This explanation is very simple; but no longer accepted (Schechner 297). The bottom up galaxy formation theory demonstrates that galaxies are formed through coalescing involving smaller progenitors; smaller particles merge and form larger or big particles. The dark matter halos cluster during the bottom up process. The age of the Earth is estimated to be 4.5 billion years. This age was approximated using radiometric system of dating; using meteorite materials. There is a hypothesis that accretion of the Earth soon started after formation of calcium-aluminum rich materials and meteorites. However; simpler explanations can indicate that the age of the Earth is millions