Introduction To Cosmology By Narlikar Pdf 127
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But the last one hundred years have seen a different sort ofcosmology: a scientific cosmology. Without running afoul of thedemarcation problem, the notable characteristics of scientificcosmology are that it uses the tools of mathematical physics (it isformalizable) and that it makes precise and testable predictions. Whathas this new scientific cosmology to do with traditional (oftentheistic) cosmologies? Has the new cosmology replaced the oldercosmologies? Does the new cosmology inform or interpret the oldercosmologies?
The puzzle we have just encountered trades on the special status ofcosmology as a historical, yet law-based science, with only one actualmodel. While theists would certainly not expect the laws of chemistryto predict that water can transform into wine, they do believe that anaccurate historical account would include reference to those miraclesthat did occur. So, is cosmology more like history, or more likechemistry? If God did create the universe, should a cosmologicaltheory report (or predict or entail) such a fact? Or should cosmologyonly be required to provide laws for universes, laws which might infact have been broken in our universe?
Finally, big-bang theology overreaches if it says that generalrelativity and the singularity theorems have settled once and for allthat the universe had a beginning in time. In fact, relativisticcosmology predicts its own invalidity for times close to a dynamicsingularity, such as the big bang. (For a dissenting opinion, seeMisner 1969.) The reason that relativistic cosmology predicts its ownown invalidity is that in the neighborhood of singularities,gravitational effects are intense, and quantum effects can be expectedto play a predominant role. But general relativity does notincorporate quantum effects, and indeed it is untested in such regimesof intense gravitational force. Thus, there is little reason tobelieve that the singularity theorems make a valid prediction aboutthe structure of a future successor theory of general relativity thatincludes quantum effects. We discuss this issue further in Section4.
It would be premature to take loop quantum cosmology as havingdecisively overturned the big-bang, finite-age cosmological model.Nonetheless, there is a non-negligible probability that it will do soin the near future; and hence there is a non-negligible probabilitythat the big bang is not the beginning of the universe, and afortiori, not the creation event (even if there was one).
We currently lack the empirical data that would distinguish betweencompeting models of quantum cosmology. But these models make differentempirical predictions from each other, and they also make differentpredictions from classical relativistic cosmology. Hence, it is anempirical, rather than a metaphysical, question whether the big bangwas the beginning of the universe.
Swinburne joins several other philosophers and physicists in seeingphysical cosmology as providing key data for a new design argument.The strength of such fine-tuning arguments continues to be a hotly contested issue among philosophers(see Collins 2009, Colyvan et al. 2005, McGrew et al. 2001, White2000).
The theological problems related to an infinitely large universe arenot specifically related to modern physical cosmology but have beendiscussed since the early days of Christianity. On the other hand,they may be seen as even more relevant today, when the favoredcosmological model has zero curvature, meaning that space is flat.Although a flat cosmic space does not necessarily imply an infiniteuniverse, many cosmologists assume that the universe is indeedspatially infinite.
By pointing out some of the subtleties in the relationship betweenscientific cosmology and theology, we do not intend to claim that thetwo are nonoverlapping magisteria (to borrow a phrase from Stephen JayGould). To the contrary, contemporary cosmology is fascinatingprecisely because it has such intricate logical relations withtraditional metaphysical and theological issues.
Es-Souni, Mohammed ; Pamir Alpay, S. ; Sritharan, Thirumany ; Prellier, Wilfrid ; Waghmare, Umesh V. (2007)Multiferroics: introduction Journal of Materials Research, 22 (8). pp. 2051-2052. ISSN 0884-2914 2b1af7f3a8