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arXiv · 1205.5901

Causality from dynamical symmetry: an example from local scale-invariance

Malte Henkel
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Abstract

Physical ageing phenomena far from equilibrium naturally lead to dynamical scaling. It has been proposed to consider the consequences of an extension to a larger Lie algebra of local scale-transformation. The best-tested applications of this are explicitly computed co-variant two-point functions which have been compared to non-equilibrium response functions in a large variety of statistical mechanics models. It is shown that the extension of the Schr\"odinger Lie algebra $\mathfrak{sch}(1)$ to a maximal parabolic sub-algebra, when combined with a dualisation approach, is sufficient to derive the causality condition required for the interpretation of a two-point function as a physical response function. The proof is presented for the recent logarithmic extension of the differential operator representation of the Schr\"odinger algebra.

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Malte Henkel. 2012-05-26. Causality from dynamical symmetry: an example from local scale-invariance. https://doi.org/10.1007/978-3-642-55361-5

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