Scientists have been examining data from scans of the cosmic background radiation for a while now, and separate groups of them have over the past few months, alternately, discovered concentric circles pointing toward cyclicality, and found bruises where universes would have jostled against one another, that point toward M-theory. From The Physics arXiv Blog:
Last month, Roger Penrose at the University of Oxford and Vahe Gurzadyan at Yerevan State University in Armenia announced that they had found patterns of concentric circles in the cosmic microwave background, the echo of the Big Bang.
This, they say, is exactly what you’d expect if the universe were eternally cyclical. By that, they mean that each cycle ends with a big bang that starts the next cycle. In this model, the universe is a kind of cosmic Russian Doll, with all previous universes contained within the current one.
That’s an extraordinary discovery: evidence of something that occurred before the (conventional) Big Bang.
Today, another group says they’ve found something else in the echo of the Big Bang. These guys start with a different model of the universe called eternal inflation. In this way of thinking, the universe we see is merely a bubble in a much larger cosmos. This cosmos is filled with other bubbles, all of which are other universes where the laws of physics may be dramatically different to ours.
These bubbles probably had a violent past, jostling together and leaving “cosmic bruises” where they touched. If so, these bruises ought to be visible today in the cosmic microwave background.
I don’t throw in with either theory, as either one would be really cool. The discovery of bruises is more recent, though, so it’s at least the one I’ll be thinking more about for the foreseeable future. One way or another, scientists will have a bigger dataset to play with, when the Planck mission starts returning some data. I was very pleased to note that arXiv points out themselves: ‘these effects could easily be a trick of the eye. As Feeney and co acknowledge: “it is rather easy to fifind [sic] all sorts of statistically unlikely properties in a large dataset like the CMB.” ‘
Whether they’re a trick of the eye or not, almost doesn’t matter. What we’re doing is looking at the evidence, and developing hypotheses and ways to test these hypotheses. This pursuit of knowledge is fundamentally what defines us as a species. Stuff like this makes me happy.