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arXiv · 0910.3374

Is cosmology just a plausibility argument?

David W. Hogg
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Abstract

I review the basis and limitations of plausible inference in cosmology, in particular the limitation that it can only provide fundamentally true inferences when the hypotheses under consideration form a set that is exhaustive. They never do; this recommends abandoning realism. Despite this, we can adopt a scientifically correct pragmatism and understand aspects of the cosmological model with enormous confidence. I illustrate these points with discussion of one certainty--expansion--and two current controversies--the existence of large extra dimensions and the possibility that the matter distribution forms a fractal on large scales. I argue that the existence of large extra dimensions is certainly plausible, but a fractal universe is untenable.

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David W. Hogg. 2009-10-18. Is cosmology just a plausibility argument?. https://arxiv.org/abs/0910.3374

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