The continuum limit of the Poland-Scheraga DNA denaturation model

Richard Dengler

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arXiv · 2603.29637

The continuum limit of the Poland-Scheraga DNA denaturation model

Richard Dengler

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Abstract

Using a field theory equivalent to a lattice version of the Poland-Scheraga model, the phase diagram for a long DNA molecule is derived in closed form. For the generalized model with excluded-volume interactions a one-loop renormalization group calculation shows that there are two stable fixed points. At both fixed points, the excluded-volume effect plays a role. At the fixed point reached when the original excluded-volume effect is weak, the phase transition is continuous. At the other fixed point, the phase transition is first order.

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Richard Dengler. 2026-03-31. The continuum limit of the Poland-Scheraga DNA denaturation model. https://arxiv.org/abs/2603.29637

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