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Ageing in the contact process: Scaling behavior and universal features

Florian Baumann·Andrea Gambassi
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Abstract

We investigate some aspects of the ageing behavior observed in the contact process after a quench from its active phase to the critical point. In particular we discuss the scaling properties of the two-time response function and we calculate it and its universal ratio to the two-time correlation function up to first order in the field-theoretical epsilon-expansion. The scaling form of the response function does not fit the prediction of the theory of local scale invariance. Our findings are in good qualitative agreement with recent numerical results.

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Florian Baumann, Andrea Gambassi. 2006-10-10. Ageing in the contact process: Scaling behavior and universal features. https://doi.org/10.1088/1742-5468%2F2007%2F01%2Fp01002

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