Once upon a time I did a little science at Uni. I'd now be really curious to understand a bit more behind the amazing difference between a freshly brewed beer and one that's matured on yeast for some time. Anyone found any interesting articles, links or know a bit themselves?
Amateur and scientific interest in beermaking is increasing, but it is a much younger subject than that of winemaking. I would direct you to research done on wine maturation for an answer to your question. Keep in mind though, that strong scientific research will likely be limited. Any huge breakthroughs discovered by a company's internal lab would probably be kept as a trade secret.
Some basic internet starting points:
As for stronger research, there are a few references in those articles, as well as external links; such resources may point you to others. Additionally, a Google Scholar search for wine maturation shows some good initial results. A similar search for beer maturation looks really scientific.
This is an interesting question, and a similar one was asked here. However, it was not answered definitively ...