We study the link between three seeming-disparate cases of self-avoiding polymers: strongly overlapping multiple chains in dilute solution, chains under spherical confinement, and the onset of semidilute solutions. Our main result is that the free energy for overlapping n chains is independent of chain length and scales as n9=4, slowly crossing over to n3, as n increases. For strongly confined polymers inside a spherical cavity, we show that rearranging the chains does not cost an additional free energy. Our results imply that, during cell cycle, global reorganization of eukaryotic chromosomes in a large cell nucleus could be readily achieved.

Phys. Rev. Lett.

Jun, S., Arnold, A., & Ha, B.-Y. (2007). Confined space and effective interactions of multiple self-avoiding chains. Phys.Rev.Lett., 98(Article number: 128303), 1–4. doi:10.1103/physrevlett.98.128303