In the last few years the problem of understanding the ultra-early universe has come into focus. We now know the key properties of the universe?its density, its age, and its main constituents. Indeed the last three years will go down as specially remarkable in the annals of cosmology because just within these years weve pinned down the shape and contents of the universe, just as in earlier centuries the pioneer navigators determined the size of the earth and the layout of its continents. The challenge now is to explain how it got that way. The new physics is attempting to understand why its expanding the way it is, and why it ended up with the content it has. We can trace its history back to about a micro-second after the putative big bang that started it off, but what happened in that first, formative microsecond? The boisterous variety of ideas being discussed?branes, inflation, etc.?makes clear that the issues are fascinating, but also were still a long way from the right answer. Were at the stage where all possibilities should be explored. Its worthwhile to consider the consequences of even the most flaky ideas, although the chance of any of them actually panning out in the long run is not very high.
http://www.edge.org/3rd_culture/rees02/rees02_index.html
