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Ground-States of Two Directed Polymers

V. T. Petaja·M. J. Alava·H. Rieger
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Abstract

Joint ground states of two directed polymers in a random medium are investigated. Using exact min-cost flow optimization the true two-line ground-state is compared with the single line ground state plus its first excited state. It is found that these two-line configurations are (for almost all disorder configurations) distinct implying that the true two-line ground-state is non-separable, even with 'worst-possible' initial conditions. The effective interaction energy between the two lines scales with the system size with the scaling exponents 0.39 and 0.21 in 2D and 3D, respectively.

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V. T. Petaja, M. J. Alava, H. Rieger. 2000-04-10. Ground-States of Two Directed Polymers. https://doi.org/10.1142/s012918310100181x

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