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Is our Universe natural?

Nature volume 440, pages 1132–1136 (2006)Cite this article

Abstract

It goes without saying that we are stuck with the Universe we have. Nevertheless, we would like to go beyond simply describing our observed Universe, and try to understand why it is that way rather than some other way. When considering both the state in which we find our current Universe, and the laws of physics it obeys, we discover features that seem remarkably unnatural to us. Physicists and cosmologists have been exploring increasingly ambitious ideas in an attempt to explain how surprising aspects of our Universe can arise from simple dynamical principles.

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Figure 1: A possible space-time diagram for the Universe on ultra-large scales.

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Acknowledgements

I thank A. Aguirre, J. Chen, B. Freivogel, J. Polchinski, E. Silverstein and A. Vilenkin for helpful conversations. This work was supported in part by the US Department of Energy, the National Science Foundation, and the David and Lucile Packard Foundation.

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  1. Department of Physics and Kavli Institute for Cosmological Physics, Enrico Fermi Institute, University of Chicago, 5640 South Ellis Avenue, Chicago, 60637, Illinois, USA

    Sean M. Carroll

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Carroll, S. Is our Universe natural?. Nature 440, 1132–1136 (2006). https://doi.org/10.1038/nature04804

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