https://doi.org/10.1140/epjb/e2002-00249-y
Topological and geometrical entanglement in a model of circular DNA undergoing denaturation
1
INFM-Dipartimento di Fisica, Università di Padova, 35131 Padova, Italy
2
Sezione INFN, Università di Padova, 35131 Padova, Italy
Corresponding author: a baiesi@pd.infn.it
Received:
8
May
2002
Published online:
13
August
2002
The linking number (topological entanglement) and the
writhe (geometrical entanglement) of a model of circular
double stranded DNA undergoing a thermal denaturation transition
are investigated by Monte Carlo simulations.
By allowing the linking number to fluctuate freely in equilibrium we see
that the linking probability undergoes an abrupt variation (first-order)
at the denaturation transition, and stays close to 1
in the whole native phase.
The average linking number is almost zero in the denatured phase
and grows as the square root of the chain length, N,
in the native phase.
The writhe of the two strands grows as 
in both phases.
PACS: 87.14.Gg – DNA, RNA / 87.15.Aa – Theory and modeling; computer simulation / 05.70.Jk – Critical point phenomena
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2002
