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Published online 2 January 2009 | Nature | doi:10.1038/news.2008.1343
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Galaxies' collision history revealed
Massive mergers sparked bursts of star formation when the Universe was half its age.
Nearly all massive galaxies have undergone at least one major merger since the Universe was 6 billion years old, according to the largest survey of their shape and structure to date.
Reconstructing how galaxies have merged is a vital part of understanding their evolution.
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Then [Fermi] delivered his verdict in a quiet, even voice. "There are two ways of doing calculations in theoretical physics", he said. "One way, and this is the way I prefer, is to have a clear physical picture of the process that you are calculating. ..." A meeting with Enrico Fermi, Freeman Dyson, Nature 427, 297 (2004) Unfortunately, cosmology today is still to get that ?clear physical picture?. Galaxies indeed are born by fragmentation (successive bifurcations) of quasars. And, with this clear and simple picture in perspective, where (1) and (2) would help with all details, every single (verified) observation is seen to fall snugly into place. Typically, here, ?They also found a close match between the timing of the mergers and the starburst episodes.? Now, we simply replace ?mergers? with ?separations,? and what do we see? Nuclear splitting is the most violent of processes. Intense episodes of star formation would thus peak at these very epochs (of flying shrapnel)! Please do take a second look, Ladies and Gentlemen, and kindly correct your picture for good. Thank you. (1) www.sittampalam.net/TheCosmos.htm (2) www.sittampalam.net/TheGalaxy.htm