Critical phenomena of RNA-like polymers -- a synopsis

R. Dengler

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arXiv · 2310.06126

Critical phenomena of RNA-like polymers -- a synopsis

R. Dengler

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Abstract

This work examines field theories for RNA-like polymers with single strand and double strand polymers and a periodic base sequence. These field theories originate from lattice models, describe polymers in a good solvent, and in principle exactly describe the critical behavior. A central role is played by the conventional one-component branched polymer and the mapping of the corresponding field theory to the Lee-Yang field theory in two less dimensions. Critical phenomena in the context of polymers as well as the Lee-Yang model entail pecularities, which we derive in detail. A new result is that the critical point of RNA-like branched polymers (with periodic base sequence) looks like the critical point of the classical one-component branched polymer, but with one more critical exponent for the single strand polymer. A random base sequence generates additional relevant interactions, and invalidates the simple picture.

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R. Dengler. 2023-10-09. Critical phenomena of RNA-like polymers -- a synopsis. https://arxiv.org/abs/2310.06126

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