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Measuring Cosmic Defect Correlations in Liquid Crystals

Rajarshi Ray·Ajit M. Srivastava
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Abstract

From the theory of topological defect formation proposed for the early universe, the so called Kibble mechanism, it follows that the density correlation functions of defects and anti-defects in a given system should be completely determined in terms of a single length scale $ξ$, the relevant domain size. Thus, when lengths are expressed in units of $ξ$, these distributions should show universal behavior, depending only on the symmetry of the order parameter, and space dimensions. We have verified this prediction by analyzing the distributions of defects/anti-defects formed in the isotropic-nematic phase transition in a thin layer of nematic liquid crystals. Our experimental results confirm this prediction and are in reasonable agreement with the results of numerical simulations.

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Rajarshi Ray, Ajit M. Srivastava. 2001-11-15. Measuring Cosmic Defect Correlations in Liquid Crystals. https://doi.org/10.1103/physrevd.69.103525

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