Abstract.
We discuss general features of noise and fluctuations in active polar gels close to and away from equilibrium. We use the single-component hydrodynamic theory of active polar gels built by Kruse and coworkers to describe the cytoskeleton in cells. Close to equilibrium, we calculate the response function of the gel to external fields and introduce Langevin forces in the constitutive equations with correlation functions respecting the fluctuation-dissipation theorem. We then discuss the breakage of the fluctuation-dissipation theorem due to an external field such as the activity of the motors. Active gels away from equilibrium are considered at the scaling level. As an example of application of the theory, we calculate the density correlation function (the dynamic structure factor) of a compressible active polar gel and discuss possible instabilities.
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F. Jülicher, K. Kruse, J. Prost, J.F. Joanny, Phys. Rep. 449, 3 (2007).
V. Narayan, S. Ramaswamy, S. Menon, Science 317, 105 (2007).
J. Toner, Y. Tu, Phys. Rev. Lett. 75, 4326 (1995).
B. Alberts, Molecular Biology of the Cell, 4th edition (Garland, New York, 2002).
R.A. Simha, S. Ramaswamy, Phys. Rev. Lett. 89, 058101 (2002).
Y. Hatwalne, S. Ramaswamy, M. Rao, R.A. Simha, Phys. Rev. Lett. 92, 118101 (2004).
K. Kruse, J.F. Joanny, F. Jülicher, J. Prost, K. Sekimoto, Phys. Rev. Lett. 92, 078101 (2004).
K. Kruse, J.F. Joanny, F. Jülicher, J. Prost, K. Sekimoto, Eur. Phys. J. E 16, 5 (2005).
K. Kruse, F. Jülicher, Phys. Rev. Lett. 85, 1778 (2000).
K. Kruse, F. Jülicher, Phys. Rev. E 67, 051913 (2003).
T.B. Liverpool, M.C. Marchetti, Phys. Rev. Lett. 90, 138102 (2003).
A. Ahmadi, T.B. Liverpool, C.M. Marchetti, Phys. Rev. E 72, 060901 (2005).
K. Kruse, J.F. Joanny, F. Jülicher, J. Prost, Phys. Biol. 3, 130 (2006).
G. Salbreux, J.F. Joanny, J. Prost, P. Pullarkat, Phys. Biol. 4, 268 (2007).
R. Voituriez, J.F. Joanny, J. Prost, Europhys. Lett. 70, 404 (2005).
D. Bray, Cell Movements, 2nd edition (Garland, New York, 2001).
J. Howard, Mechanics of Motor Proteins and the Cytoskeleton (Sinauer Associates, Inc., Sunderland, 2001).
D. Mizuno, C. Tardin, C.F. Schmidt, F.C. MacKintosh, Proc. Sci. 315, 370 (2007).
D. Chandler, Introduction to Modern Statistical Physics (Oxford University Press, Oxford, 1987).
R. Larson, Constitutive Equations for Polymer Melts and Solutions (Butterworths, London, 1988).
R. Voituriez, J.F. Joanny, J. Prost, Phys. Rev. Lett. 96, 028102 (2006).
D. Foster, Hydrodynamic Fluctuations, Broken Symmetry and Correlation Fluctuations (Addison-Wesley, Redwood City, 1983).
J. Harden, H. Pleiner, P. Pincus, J. Chem. Phys. 94, 5208 (1991).
J.F. Joanny, F. Jülicher, K. Kruse, J. Prost, New J. Phys. 9, 422 (2007).
Jean Zinn-Justin, Quantum Field Theory and Critical Phenomena (Oxford University Press, 2002).
G.E. Crooks, Phys. Rev. E 60, 2721 (1999).
G. Gallavotti, E.G.D. Cohen, Phys. Rev. Lett. 74, 2694 (1995).
C. Jarzynski, Phys. Rev. Lett. 78, 2690 (1997).
G.N. Bochkov, Y.E. Kuzolev, Physica A 106, 443 (1981).
J. Kurchan, J. Phys. A 31, 3719 (1998).
B. Nadrowsky, P. Martin, F. Jülicher, Proc. Natl. Acad. Sci. U.S.A. 101, 12195 (2004).
F. Jülicher, A. Ajdari, J. Prost, Rev. Mod. Phys. 69, 1269 (1997).
A. Lau, T. Lubensky, Fluctuating hydrodynamics and microrheology of a dilute suspension of swimming bacteria, preprint (2008).
A. Lau, T. Lubensky, Phys. Rev. E 76, 011123 (2007).
P. Chaikin, T. Lubensky, Principles of Condensed Matter Physics (Cambridge University Press, Cambridge, 2000).
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Basu, A., Joanny, J.F., Jülicher, F. et al. Thermal and non-thermal fluctuations in active polar gels. Eur. Phys. J. E 27, 149–160 (2008). https://doi.org/10.1140/epje/i2008-10364-9
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DOI: https://doi.org/10.1140/epje/i2008-10364-9