Subgaussian concentration and rates of convergence in directed polymers
Nikolaos Zygouras (University of Warwick)
Abstract
We consider directed random polymers in $(d+1)$ dimensions with nearly gamma i.i.d. disorder. We study the partition function $Z_{N,\omega}$ and establish exponential concentration of $\log Z_{N,\omega}$ about its mean on the subgaussian scale $\sqrt{N/\log N}$ . This is used to show that $\mathbb{E}[ \log Z_{N,\omega}]$ differs from $N$ times the free energy by an amount which is also subgaussian (i.e. $o(\sqrt{N})$), specifically $O( \sqrt{\frac{N}{\log N}}\log \log N)$
Full Text: Download PDF | View PDF online (requires PDF plugin)
Pages: 1-28
Publication Date: January 11, 2013
DOI: 10.1214/EJP.v18-2005
References
- Alexander, Kenneth S. Lower bounds on the connectivity function in all directions for Bernoulli percolation in two and three dimensions. Ann. Probab. 18 (1990), no. 4, 1547--1562. MR1071808
- Alexander, Kenneth S. A note on some rates of convergence in first-passage percolation. Ann. Appl. Probab. 3 (1993), no. 1, 81--90. MR1202516
- Alexander, Kenneth S. Approximation of subadditive functions and convergence rates in limiting-shape results. Ann. Probab. 25 (1997), no. 1, 30--55. MR1428498
- Alexander, Kenneth S. Power-law corrections to exponential decay of connectivities and correlations in lattice models. Ann. Probab. 29 (2001), no. 1, 92--122. MR1825143
- Alexander, K. S. Subgaussian rates of convergence of means in directed first passage percolation. (2011) arXiv:1101.1549
- Borodin, A., Corwin, I., Remenik, D. Log-Gamma polymer free energy fluctuations via a Fredholm determinant identity (2012) arXiv:1206.4573
- Benaïm, Michel; Rossignol, Raphaël. Exponential concentration for first passage percolation through modified Poincaré inequalities. Ann. Inst. Henri Poincaré Probab. Stat. 44 (2008), no. 3, 544--573. MR2451057
- Benjamini, Itai; Kalai, Gil; Schramm, Oded. First passage percolation has sublinear distance variance. Ann. Probab. 31 (2003), no. 4, 1970--1978. MR2016607
- Chatterjee, S., The universal relation between scaling exponents in first-passage percolation, arXiv:1105.4566
- Chatterjee, S., Disorder chaos and multiple valleys in spin glasses, (2009) arXiv:0907.3381
- Comets, Francis; Shiga, Tokuzo; Yoshida, Nobuo. Directed polymers in a random environment: path localization and strong disorder. Bernoulli 9 (2003), no. 4, 705--723. MR1996276
- Comets, Francis; Yoshida, Nobuo. Directed polymers in random environment are diffusive at weak disorder. Ann. Probab. 34 (2006), no. 5, 1746--1770. MR2271480
- Corwin, I., O'Connel, N.M., Seppäläinen, T., Zygouras, N., Tropical combinatorics and Whitaker functions, (2011) arXiv:1110.3489
- Graham, B. Sublinear variance for directed last passage percolation phJournal Th. Prob. (2010)
- Johansson, Kurt. Shape fluctuations and random matrices. Comm. Math. Phys. 209 (2000), no. 2, 437--476. MR1737991
- Kardar, M., Parisi, G., Zhang, Y.C., Dynamic scaling of growing interfaces phPhys. Rev. Lett. 56 (1986), 889--892
- Kesten, Harry. On the speed of convergence in first-passage percolation. Ann. Appl. Probab. 3 (1993), no. 2, 296--338. MR1221154
- Krug, J., Spohn, H., Kinetic roughening of growing surfaces ph In Solids Far From Equilibrium: Growth, Morphology and Defects (C. Godreche, ed.). Cambridge Univ. Press. (1991)
- Ledoux, Michel. The concentration of measure phenomenon. Mathematical Surveys and Monographs, 89. American Mathematical Society, Providence, RI, 2001. x+181 pp. ISBN: 0-8218-2864-9 MR1849347
- Wüthrich, Mario V. Scaling identity for crossing Brownian motion in a Poissonian potential. Probab. Theory Related Fields 112 (1998), no. 3, 299--319. MR1660910
- Seppäläinen, Timo. Scaling for a one-dimensional directed polymer with boundary conditions. Ann. Probab. 40 (2012), no. 1, 19--73. MR2917766
- Piza, M. S. T. Directed polymers in a random environment: some results on fluctuations. J. Statist. Phys. 89 (1997), no. 3-4, 581--603. MR1484057

This work is licensed under a Creative Commons Attribution 3.0 License.