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Random RNA under tension

Francois David·Christian Hagendorf·Kay Joerg Wiese
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Abstract

The Laessig-Wiese (LW) field theory for the freezing transition of random RNA secondary structures is generalized to the situation of an external force. We find a second-order phase transition at a critical applied force f = f_c. For f < f_c forces are irrelevant. For f > f_c, the extension L as a function of pulling force f scales as (f-f_c)^(1/gamma-1). The exponent gamma is calculated in an epsilon-expansion: At 1-loop order gamma = epsilon/2 = 1/2, equivalent to the disorder-free case. 2-loop results yielding gamma = 0.6 are briefly mentioned. Using a locking argument, we speculate that this result extends to the strong-disorder phase.

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Francois David, Christian Hagendorf, Kay Joerg Wiese. 2007-05-08. Random RNA under tension. https://doi.org/10.1209/0295-5075%2F78%2F68003

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