Penrose Proposes Pre Big Bang Universe




My only comment on this bit of cosmic speculation is to wonder why weneeded such an esoteric explanation for a curious and suggestiveobservation.  We have now observedconcentric rings in the microwave background in which the temperature is lower(or older?)

Perhaps we do not knowwhat we are talking about.  Perhaps weare developing an instrumental effect. Perhaps we are looking through a lens effect that is otherwise unseen.  I like the last explanation best.  Otherwise this is reminiscent of Ptolemaic reversing orbits. 

Cosmology has beenspeculation built on speculation and founded on an interpretation called thebig bang that has been accepted into the canon of orthodoxy dispite its slimcontribution to the debate.  It is infact a simplistic interpretation of the data.

Everybody forgets justhow tentative these original ideas were when proposed in the face of a lack ofbetter ideas.  Cosmology based on leastbad ideas makes me nervous and has made me nervous for forty years.

Sometimes it is betterto spare the speculation and simply wait for more data such as additional ringselsewhere in the sky.

Penrose claims to have glimpsed universe beforeBig Bang


NOVEMBER 23, 2010




Circular patterns within the cosmic microwave backgroundsuggest that space and time did not come into being at the Big Bang but thatour universe in fact continually cycles through a series of "aeons". Thatis the sensational claim being made by University of Oxfordtheoretical physicist Roger Penrose, who says that data collected by NASA'sWMAP satellite support his idea of "conformal cyclic cosmology". Thisclaim is bound to prove controversial, however, because it opposes the widelyaccepted inflationary model of cosmology. 


Penrose takes issue with the inflationary picture (inflation after a big bang)and in particular believes it cannot account for the very low entropy state inwhich the universe was believed to have been born – an extremely high degree oforder that made complex matter possible. He does not believe that space andtime came into existence at the moment of the Big Bang but that the Big Bangwas in fact just one in a series of many, with each big bang marking the startof a new "aeon" in the history of the universe. 




Arxiv- Concentric circles in WMAP data may provide evidence of violent pre-Big-Bangactivity


Central to Penrose's theory is theidea that in the very distant future the universe will in one sense become verysimilar to how it was at the Big Bang. He says that at these points the shape,or geometry, of the universe was and will be very smooth, in contrast to itscurrent very jagged form. This continuity of shape, he maintains, will allow atransition from the end of the current aeon, when the universe will haveexpanded to become infinitely large, to the start of the next, when it onceagain becomes infinitesimally small and explodes outwards from the next bigbang. Crucially, he says, the entropy at this transition stage will beextremely low, because black holes, which destroy all information that theysuck in, evaporate as the universe expands and in so doing remove entropy fromthe universe.


Penrose now claims to have found evidence for this theory in the cosmicmicrowave background, the all-pervasive microwave radiation that was believedto have been created when the universe was just 300,000 years old and whichtells us what conditions were like at that time. The evidence was obtained byVahe Gurzadyan of the Yerevan Physics Institute in Armenia,who analysed seven years' worth of microwave data from WMAP, as well as datafrom the BOOMERanG balloon experiment in Antarctica.Penrose and Gurzadyan say they have clearly identified concentric circleswithin the data – regions in the microwave sky in which the range of theradiation's temperature is markedly smaller than elsewhere. 


The circles, they say, are the marks left in our aeon by the spherical ripplesof gravitational waves that were generated when black holes collided in theprevious aeon. And they say that these circles pose a problem for inflationarytheory because this theory says that the distribution of temperature variationsacross the sky should be Gaussian, or random, rather than having discernablestructures within it.




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